SPR 2023 | Geography Current Affairs Compilation for Prelims 2023

 

 

Economic Geography:

HIGH-GRADE LITHIUM

• Context– Recently, high-grade lithium was discovered in Nigeria.
• Findings
  • The discovery does not equate to a commercial find. In fact, it should be taken only as a first step in the long journey to be established as a commercially viable deposit that can be mined and extracted.
  • In Nigeria, lithium minerals (spodumene and lepidolite) are known to be associated with cassiterite, columbite-tantalite (coltan) and others in the extensive belt of rare metal-bearing rock types called pegmatite.
  • The Geological Agency described the lithium as high grade because what’s been found has between 1-13 per cent oxide content. Normally exploration begins at levels as low as 0.4 percent.
• Lithium and its importance-
  • Grade (in percent) is a measure of concentration of the lithium in the minerals and or rocks that contain it.
  • Therefore, the higher the grade the more the economic viability.
  • Lithium is a metallic mineral in very high demand by manufacturing industries.
  • In nature it tends to concentrate sufficiently in the two minerals, spodumene and lepidolite.
  • Otherwise it will occur dispersed in minerals but not sufficient enough to be of economic consideration.
  • They are usually found in specialised rocks called rare metal-bearing pegmatites and greisens.
  • Earlier the bulk of demand for lithium was split between ceramics and glasses (35 per cent) and greases, metallurgical powders, polymers, and other industrial uses (over 35 per cent). Less than 30 per cent was for batteries.
  • But by 2030, batteries are expected to account for 95 percent of demand.
  • Lithium-ion batteries are generally more expensive but have better performance and are becoming the preferred technology. 
    • The different types are:
      • Lithium-cobalt oxide battery– It is used in consumer electronics and is finding application in electric vehicles. It is relatively cheap.
      • Lithium-nickel-manganese-cobalt is a newer, higher performing range of battery chemistry. It is mainly developed for the electronic vehicle market but is finding a wider use because of its increasing cost effectiveness.
      • Lithium iron phosphate, the safest technology with relatively high performance but relatively expensive. It is very popular in China but is likely to become overtaken by Lithium-nickel-manganese-cobalt over the longer term; and
      • Lithium-nickel-cobalt-aluminium oxide was developed to reduce cobalt consumption and is known as a solid performer and of reasonable cost.
  • Lithium-ion batteries are used in mobile phones, computers, electronics, energy storage systems and electric vehicles.
  • Lithium and most lithium minerals are mined along with other high-value metallic minerals such as tin, niobium-tantalum (columbite-tantalite) and uranium (in pyrochlore).
  • Greenbushes mine in Western Australia is the largest hard-rock lithium mine in the world. Tantalum is also mined there.
  • Due to the growing interest in clean energy, the demand for lithium has skyrocketed as most countries draw plans to phase out fossil fuel vehicles and switch to zero-emission electric vehicles.
• Lithium Production
  • Lithium production globally grew from 28,100 metric tonnes in 2010 to 86,000 in 2019.
  • Three countries, Australia (40,000 tonnes), Chile (20,600 tonnes) and China (14,000 tonnes) mine about 86 per cent of the world’s lithium.
  • Others are Argentina, Brazil, Zimbabwe, USA and Portugal.
  • The largest importers of lithium are South Korea, China, Japan, US and Belgium.
  • Lithium price was average of $2,000 per metric tonne in 2002 rising to $18,000 in 2018.
  • The lithium supply chain involves converting lithium minerals to lithium concentrates and lithium hydroxides.
• Lithium reserves in India
  • India currently imports lithium and the majority is routed through China.
  • The Geological Survey of India also works on the probable location of reserves in 6 states of Arunachal Pradesh, Andhra Pradesh, Chhattisgarh, Jharkhand, Rajasthan, and in the Union Territory of Jammu and Kashmir and the Department of Atomic energy conducted surveys in Karnataka and Rajasthan.
  • In 2021, the Department of Atomic Energy discovered the country’s first lithium reserve of 1600 tonnes in Mandya, Karnataka.
  • It has an estimated lithium reserves of 14,100 tonnes.
  • In the 2022-23 Union Budget, the Finance minister announced a separate battery swapping policy alongside the government’s Faster Adoption of Hybrid and Electric Vehicles (FAME) scheme.

REE – Rare Earth Elements

Context: A group of western nations are cooperating to develop alternatives to China to ensure key industrial supplies. India is not part of this arrangement — called the Minerals Security Partnership (MSP).

What Are Rare Earth Elements (REEs)?

• Rare earth elements are a group of seventeen chemical elements that occur together in the periodic table.
• The group consists of yttrium and the 15 lanthanide elements (lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium).
• Scandium is found in most rare earth element deposits and is sometimes classified as a rare earth element.
• The rare earth elements are all metals, and the group is often referred to as the “rare earth metals.” These metals have many similar properties, and that often causes them to be found together in geologic deposits. They are also referred to as “rare earth oxides” because many of them are typically sold as oxide compounds.

What are the uses of Rare Earth Elements?

• Rare earth metals and alloys that contain them are used in many devices that people use every day such as computer memory, DVDs, rechargeable batteries, cell phones, catalytic converters, magnets, fluorescent lighting and much more
• During the past twenty years, there has been an explosion in demand for many items that require rare earth metals. The use of rare earth elements in computers has grown almost as fast as cell phones.
• Many rechargeable batteries are made with rare earth compounds. Several pounds of rare earth compounds are in batteries that power every electric vehicle and hybrid-electric vehicle.
  • As concerns for energy independence, climate change, and other issues drive the sale of electric and hybrid vehicles, the demand for batteries made with rare earth compounds will climb even faster.
• Rare earths are used as catalysts, phosphors, and polishing compounds. These are used for air pollution control, illuminated screens on electronic devices, and the polishing of optical-quality glass. All of these products are expected to experience rising demand.

Are These Elements Really “Rare”?

• Rare earth elements are not as “rare” as their name implies. Thulium and lutetium are the two least abundant rare earth elements – but they each have an average crustal abundance that is nearly 200 times greater than the crustal abundance of gold.
• However, these metals are very difficult to mine because it is unusual to find them in concentrations high enough for economical extraction.
• The most abundant rare earth elements are cerium, yttrium, lanthanum and neodymium.
• They have average crustal abundances that are similar to commonly used industrial metals such as chromium, nickel, zinc, molybdenum, tin, tungsten, and lead. Again, they are rarely found in extractable concentrations.

Indian Context:

• Some REEs are available in India — such as Lanthanum, Cerium, Neodymium, Praseodymium and Samarium, etc.
• Others such as Dysprosium, Terbium, and Europium, which are classified as HREEs, are not available in Indian deposits in extractable quantities.
• Hence, there is a dependence on countries such as China for HREEs, which is one of the leading producers of REEs, with an estimated 70 per cent share of the global production.

WORLD POPULATION PROSPECTS

• Context
  • The World Population Prospects 2022 has projected that India will surpass China as the world’s most populous country in 2023, while the global population will reach 8 billion this year.
• What is World Population Prospect
  • The Population Division of the UN has been publishing the WPP in a biennial cycle since 1951.
  • Each revision of the WPP provides a historical time series of population indicators starting in 1950.
  • It does so by taking into account newly released national data to revise estimates of past trends in fertility, mortality or international migration.
• Findings of the Report
  
  • The world’s population continues to grow, but the pace of growth is slowing down
    • The world’s population is projected to reach 8 billion on 15 November 2022.
    • The latest projections by the United Nations suggest that the global population could grow to around 8.5 billion in 2030, 9.7 billion in 2050 and 10.4 billion in 2100.
    • Population growth is caused in part by declining levels of mortality, as reflected in increased levels of life expectancy at birth. Globally, life expectancy reached 72.8 years in 2019, an increase of almost 9 years since 1990. Further reductions in mortality are projected to result in an average longevity of around 77.2 years globally in 2050.
    • Life expectancy at birth for women exceeded that for men by 5.4 years globally, with female and male life expectancies standing at 73.8 and 68.4, respectively. A female survival advantage is observed in all regions and countries, ranging from 7 years in Latin America and the Caribbean to 2.9 years in Australia and New Zealand.
    • Following a drop in mortality, population growth continues so long as fertility remains at high levels. When fertility begins to fall, the annual rate of growth starts to drop.
    • In 2021, the average fertility of the world’s population stood at 2.3 births per woman over a lifetime, having fallen from about 5 births per woman in 1950. Global fertility is projected to decline further to 2.1 births per woman by 2050.
    • In 2020, the global growth rate fell under 1 per cent per year for the first time since 1950. The world’s population is projected to reach a peak of around 10.4 billion people during the 2080s and to remain at that level until 2100.
    • Two-thirds of the projected increase in global population through 2050 will be driven by the momentum of past growth that is embedded in the youthful age structure of the current population. Such growth would occur even if childbearing in today's high-fertility countries were to fall immediately to around two births per woman.
  • Rates of population growth vary significantly across countries and regions
    • In 2022, the two most populous regions were both in Asia: Eastern and South-Eastern Asia with 2.3 billion people (29 per cent of the global population), and Central and Southern Asia with 2.1 billion (26 per cent). China and India, with more than 1.4 billion each, accounted for most of the population in these two regions.
    • More than half of the projected increase in global population up to 2050 will be concentrated in just eight countries: the Democratic Republic of the Congo, Egypt, Ethiopia, India, Nigeria, Pakistan, the Philippines and the United Republic of Tanzania. Disparate growth rates among the world’s largest countries will re-order their ranking by size.
    • India is projected to surpass China as the world’s most populous country during 2023.
    • Countries of sub-Saharan Africa are expected to continue growing through 2100 and to contribute more than half of the global population increase anticipated through 2050.
    • Whereas the populations of Australia and New Zealand, Northern Africa and Western Asia, and Oceania (excluding Australia and New Zealand) are expected to experience slower, but still positive, growth through the end of the century, the populations of Eastern and South-Eastern Asia, Central and Southern Asia, Latin America and the Caribbean, and Europe and Northern America are projected to reach their peak size and to begin to decline before 2100.
    • The 46 least developed countries (LDCs) are among the world’s fastest-growing. Many are projected to double in population between 2022 and 2050, putting additional pressure on resources and posing challenges to the achievement of the Sustainable Development Goals (SDGs).
  • Levels and patterns of fertility and mortality vary widely around the world
    • The gap in life expectancy at birth between certain groups of countries remains wide. In 2021, life expectancy in the least developed countries lagged 7.0 years behind the global average, due largely to persistently high levels of child and maternal mortality and, in some countries, to violence and conflict or to the continuing impact of the human immunodeficiency virus (HIV) epidemic.
    • In 2021, fertility levels high enough to sustain positive growth were found in sub-Saharan Africa (4.6 births per woman), Oceania excluding Australia and New Zealand (3.1), Northern Africa and Western Asia (2.8), and Central and Southern Asia (2.3).
  • The population of older persons is increasing both in numbers and as a share of the total
    • The share of the global population aged 65 years or above is projected to rise from 10 per cent in 2022 to 16 per cent in 2050.
    • By 2050, the number of persons aged 65 years or over worldwide is projected to be more than twice the number of children under age 5 and about the same as the number of children under age 12.
    • Whereas population growth at older ages is driven by lower mortality and increased survival, an upward shift in the population age distribution is caused by a sustained drop in the fertility level.
    • Because of the female advantage in life expectancy, women outnumber men at older ages in almost all populations. Globally, women comprised 55.7 per cent of persons aged 65 or older in 2022, and their share is projected to decline slightly to 54.5 per cent by 2050.
    • Countries with ageing populations should take steps to adapt public programmes to the growing proportion of older persons, including by improving the sustainability of social security and pension systems and by establishing universal health care and long-term care systems.
  • A sustained drop in fertility leads to an increased concentration of the population at working ages, creating an opportunity for accelerated economic growth per capita
    • In most countries of sub-Saharan Africa, as well as in parts of Asia and Latin America and the Caribbean, the share of population at working ages (between 25 and 64 years) has been increasing in recent years thanks to reductions in fertility. This shift in the age distribution provides a time-bound opportunity for accelerated economic growth known as the “demographic dividend”.
    • To maximize the potential benefits of a favourable age distribution, countries need to invest in the further development of their human capital by ensuring access to health care and quality education at all ages and by promoting opportunities for productive employment and decent work.
  • More and more countries have begun to experience population decline
    • The populations of 61 countries or areas are projected to decrease by 1 per cent or more between 2022 and 2050, owing to sustained low levels of fertility and, in some cases, elevated rates of emigration.
    • Total fertility has fallen markedly in recent decades for many countries. Today, two-thirds of the global population lives in a country or area where fertility is below 2.1 births per woman, roughly the level required for zero growth in the long run for a population with low mortality.
    • Among countries with at least half a million people, the largest relative reductions in population size until 2050, with losses of 20 per cent or more, are expected to occur in Bulgaria, Latvia, Lithuania, Serbia and Ukraine.
  • International migration is having important impacts on population trends for some countries
    • In some parts of the world, international migration has become a major component of population change.
    • For high-income countries between 2000 and 2020, the contribution of international migration to population growth (net inflow of 80.5 million) exceeded the balance of births over deaths (66.2 million). Over the next few decades, migration will be the sole driver of population growth in high-income countries. By contrast, for the foreseeable future, population increase in low-income and lower-middle-income countries will continue to be driven by an excess of births over deaths.
    • Between 2010 and 2021, 40 countries or areas experienced a net inflow of more than 200,000 migrants each; in each of 17 of them, the net inflow over this period exceeded 1 million people. For several of the top receiving countries, including Jordan, Lebanon and Türkiye, high levels of immigration in this period were driven mostly by refugee movements, in particular from Syrian Arab Republic.
    • All countries, whether experiencing net inflows or outflows of migrants, should take steps to facilitate orderly, safe, regular and responsible migration, in accordance with SDG target 10.7.
  • The COVID-19 pandemic has affected all components of population change, including fertility, mortality and migration
    • Global life expectancy at birth fell to 71.0 years in 2021, down from 72.8 in 2019, due mostly to the impact of the coronavirus disease (COVID-19) pandemic.
    • The pandemic’s impact on life expectancy has varied across regions and countries. In Central and Southern Asia and in Latin America and the Caribbean, life expectancy at birth fell by almost three years between 2019 and 2021. By contrast, the combined population of Australia and New Zealand gained 1.2 years due to lower mortality risks during the pandemic for some causes of death. In some countries, the pandemic has been responsible for a significant reduction in life expectancy at birth. For Bolivia (Plurinational State of), Botswana, Lebanon, Mexico, Oman and the Russian Federation, estimates of life expectancy at birth declined by more than 4 years between 2019 and 2021.
    • The COVID-19 pandemic severely restricted all forms of human mobility, including international migration. The magnitude of the pandemic’s impact on migration trends is difficult to ascertain due to data limitations.
  • Population data provide critical information for use in development planning
    • The quality of population estimates and projections hinges on the collection of reliable and timely demographic data, including through civil registration and vital statistics systems, population censuses, population registers and household surveys.
    • The COVID-19 pandemic has affected many data collection operations worldwide. Countries and development partners should give priority to the ongoing 2020 round of national population censuses, as such data provide critical information to inform development planning and to assess progress towards the achievement of the SDGs.
• Findings related to India
  • India’s growth rate stood at 2.3 % in 1972, which has dropped down to less than 1% now.
  • In this period, the number of children each Indian woman has during her lifetime has come down from about 5.4 to less than 2.1 now.
  • This means that Indian has attained the Replacement Fertility Rate, at which a population exactly replaces itself from one generation to the next.
  • Fertility rates have been declining, so have mortality rates with increased access to healthcare and advances in medicine.
  • Population of 0-14 years and 15-24 years will continue to decline while those of 25-64 and 65+ will continue to rise for the coming decades.
  • This reduction of premature mortality for successive generations, reflected in increased levels of life expectancy at birth, has been a driver of population growth in India.

• Recommendations
  • Countries with ageing populations should take steps to adapt public programmes to the growing proportion of older persons, including by improving the sustainability of social security and pension systems and by establishing universal health care and long-term care systems.
  • To maximize the potential benefits of a favourable age distribution, countries need to invest in the further development of their human capital by ensuring access to health care and quality education at all ages and by promoting opportunities for productive employment and decent work.
  • For those already in the 25-64 age bracket, there is a need for skilling, which is the only way to ensure they are more productive and have better incomes.

YOUTH IN INDIA 2022 REPORT

• Context
  •  The Ministry of Statistics and Programme Implementation has released the ‘Youth in India 2022’ report recently
• Key Findings
  • ndia’s favourable demographic dividend is at an inflection point of sorts, with the population share of the youth starting to taper off even as the share of the elderly is expected to steadily surge during 2021-2036. 
  • The states of Bihar and Uttar Pradesh, which experienced a rise in proportion of youth population to total population till 2021, are expected to see a decline from hereon.
  • These two states, along with Maharashtra, Madhya Pradesh and Rajasthan, are projected to have over half (52 per cent) of the country’s youth.
  • States such as Kerala, Tamil Nadu and Himachal Pradesh are projected to see a higher elderly population than the youth by 2036.
  • Citing the findings from the Report of Technical Group on Population Projections, 2020, constituted by Ministry of Health and Family Welfare, this report said youth in the age group of 15-29 years comprise 27.2 per cent of the population for 2021, which is expected to decrease to 22.7 by 2036.
  • The proportion of the population aged under 15 years is projected to decline, the elderly in the population is expected to increase. 
  • The total youth population increased from 222.7 million in 1991 to 333.4 million in 2011 and is projected to reach 371.4 million by 2021 and, thereafter, decrease to 345.5 million by 2036.
  • For Kerala, which saw the youth population peak earlier than other states, the elderly population share in total population has been projected at 16.5 per cent compared with 22.1 per cent of youth population in 2021. 
  • The share of elderly in total population (22.8 per cent) in Kerala is then projected to cross the share of youth (19.2 per cent) by 2036. 
  • Tamil Nadu and Himachal Pradesh are also projected to experience elderly population more than the youth by 2036.
  • A greater proportion of youth at present will result in a greater proportion of elderly in the population in future. This will create a demand for better healthcare facilities and development of welfare schemes/programmes for elderly people.
  • Proportion of youth to the total population had increased from 26.6 per cent in 1991 to 27.9 per cent in 2016 and then projected to start a downward trend and to reach 22.7 per cent by year 2036. 
  • On the contrary, the proportion of elderly population to the total population has increased from 6.8 per cent in 1991 to 9.2 per cent in 2016 and is projected to reach 14.9 per cent in 2036.

• Implications
  • India is experiencing a demographic window of opportunity, a “youth bulge”. However, youth come across various development challenges viz. access to education, gainful employment, gender inequality, child marriage, youth- friendly health services and adolescent pregnancy.
  • Youth bulge refers to a demographic pattern where a large share of the population is comprised of children and young adults.
  • A greater proportion of youth at present will result in a greater proportion of elderly in the population in future. This will create a demand for better healthcare facilities and development of welfare schemes/programmes for elderly people.
  • Rise in the share of elderly population will put pressure on social security and public welfare systems and the next 4-5 years need to be utilised well to accelerate productive job creation.
  • People, typically in informal employment, don’t have social security, it will add burden to the respective state.
• Recommendations
  • There is need to increase share of employment in manufacturing because people who in current labour force, when they are retire and the share of elderly starts rising in very populous states, then it will be like a ticking time bomb (a situation that is likely to become difficult to deal with or control).
  • In the next 4-5 years, there is a need for active labour market policies to be adopted to accelerate productive job creation.
  • There is a need to take steps to adapt public programmes to the growing proportion of older persons, including by improving the sustainability of social security and pension systems and by establishing universal health care and long-term care systems.

One Water Approach

• ‘One Water’ is the recognition that all water has value, regardless of its source.
• It includes managing that source in an integrated, inclusive and sustainable manner by including the community, business leaders, industries, farmers, conservationists, policymakers, academics and others for ecological and economic benefits.
• The new water management approach, that also referred to as Integrated water resources management (IWRM).
  • IWRM is an “integrated planning and implementation approach to managing finite water resources for long-term resilience and reliability meeting both community and ecosystem needs”, according to research organisation Water Research Foundation.

Features of One Water Approach:

• The mindset that all water has value — from the water resources in our ecosystems to our drinking water, wastewater and stormwater.
• A multi-faceted approach meaning that our water-related investments should provide economic, environmental, and societal returns.
• Utilising watershed-scale thinking and action that respects and responds to the natural ecosystem, geology, and hydrology of an area.
• Partnerships and inclusion in recognising that real progress and achievements will only be made when all stakeholders come forward and together will take a decision.

About water:

• Water (H2O) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a solvent).
• Water on the Earth:
  • Water covers about 71% of the Earth's surface, mostly in seas and oceans (about 96.5%).
  • Small portions of water occur as groundwater (1.7%), in the glaciers and the ice caps of Antarctica and Greenland (1.7%), and in the air as vapor, clouds (consisting of ice and liquid water suspended in air), and precipitation (0.001%).
  • Water moves continually through the water cycle of evaporation, transpiration (evapotranspiration), condensation, precipitation, and runoff, usually reaching the sea.

• Importance of water:
  • Water plays an important role in the world economy.
  • Approximately 70% of the freshwater used by humans goes to agriculture.
  • Fishing in salt and freshwater bodies is a major source of food for many parts of the world, providing 6.5% of global protein.
  • Much of the long-distance trade of commodities (such as oil, natural gas, and manufactured products) is transported by boats through seas, rivers, lakes, and canals.

Aapada Mitra Scheme

Context:

• It was published in the PIB bulletin. Thus, let's study it from a preliminary point of view.

Aapada Mitra scheme:

• The Scheme for Training of Community Volunteers in Disaster Response (Aapda Mitra)
• NDMA has been implementing a central sector scheme namely Aapda Mitra since May 2016 with a focus on training of 6000 community volunteers (200 volunteers per district) in disaster response in selected 30 most flood prone districts of 25 States of India. 
• The scheme aims to provide the community volunteers with the skills that they would need to respond to their community’s immediate needs in the aftermath of a disaster thereby enabling them to undertake basic relief and rescue tasks during emergency situations such as floods, flash-floods and urban flooding.
• The objectives of the scheme:
  •  Development and Standardization of training modules at National Level;
  • Development of Information Knowledge Management System at National level linked to States/UTs;
  • Training institutions to be empanelled by respective States/UTs at the State/UT level;
  • To train 6000 community volunteers in life saving skills of disaster response (flood relief and rescue), coordination, assistance, and provide personal protective equipment and emergency responder kits;
  • To create a Community Emergency Stockpile/Reserve at the district/block level containing essential light search and rescue equipment, medical first aid kits, etc;
  • To disseminate training and education tools developed under the project to more number of flood prone districts in subsequent phases of the scheme.
• So far, a total number of 5186 community volunteers have been trained by 23 Project States.

Kalanamak Rice

Context:

• Indian Agriculture Research Institute (IARI) successfully tested two new dwarf varieties of Kalanamak rice i.e., Pusa Narendra Kalanamak 1638 and Pusa Narendra Kalanamak 1652 in Uttar Pradesh that give double the yield.

What is Kalanamak Rice?

• Kalanamak is a traditional variety of paddy with a black husk and a strong fragrance. 
• It is a scented rice of Nepal and India.
• Its name means black husk (kala = black; the suffix ‘namak’ means salt).

• This variety has been in cultivation since the original Buddhist period (600 BC).
• It is popular in Himalayan Tarai of Nepal i.e., Kapilvastu, and eastern Uttar Pradesh, where it is known as the scented black pearl.
• It was featured in the book “Speciality Rices of the world” by the Food and Agriculture Organization of the United Nations.
• Kalanamak rice was granted the Geographical Indication (GI) Tag in 2012 by the Government of India. 
• The geographical area for Kalanamak rice lies between 26° 42′ North to 27° 75′ North Latitude and 81° 42′ to 83° 88′ East Longitude in UP. Kalanamak Rice is approved for 11 districts of Zone 7 of UP.

 

REWARD Project

Context:

• The Government of India, the State Governments of Karnataka and Odisha and the World Bank have signed a $115 million (INR 869 crore) Programme (Rejuvenating Watersheds for Agricultural Resilience through Innovative Development Programme) that will help national and state institutions adopt improved watershed management practices to help increase farmers’ resilience to climate change, promote higher productivity and better incomes.

More on the news:

• The Government of India has committed to restoring 26 million hectares of degraded land by 2030 and doubling farmers’ income by 2023.
• Effective watershed management can help enhance livelihoods in rainfed areas, while building a more resilient food system.
• In this context, the new program will help the participating state governments in their efforts to transform watershed planning and execution and adopt science-based planning that could be replicated across the country.
• It will also help the participating and others states to adopt new approaches to watershed development.
• India has one of the largest watershed management programs in the world. This programme will further advance this progress by developing and applying comprehensive spatial data and technologies, decision support tools, and knowledge exchanges.
• The International Bank for Reconstruction and Development (IBRD) financing will support Karnataka with $60 million (INR 453.5 crore), Odisha with $49 million (INR 370 crore), and the remaining $6 million (INR 45.5 crore) will be for the central government’s Department of Land Resources. The $115 million (INR 869 crore) loan has a maturity of 15 years, including a grace period of 4.5 years.

Saffron Bowl Project

Context:

• North East Centre for Technology Application and Reach (NECTAR) under Saffron Bowl project has identified few locations in Arunachal Pradesh and Meghalaya for saffron cultivation.
• In Arunachal Pradesh, there is a good growth of organic saffron with flowers.
• In Meghalaya, sample plantations were grown at Cherrapunji, Mawsmai and Lalingtop sites.

More on the news:

• Saffron production has long been restricted to a limited geographical area in the Union territory of Jammu & Kashmir.
• Pampore region, commonly known as Saffron bowl of Kashmir, is the main contributor to saffron production.
  • Pampore Saffron Heritage of Kashmir is one of the Globally Important Agricultural Heritage systems (GIAHS) recognised sites in India.
  • Recently, the Kashmir saffron got Geographical Indication (GI) tag status.

Saffron: It is a plant whose dried stigmas (thread-like parts of the flower) are used to make saffron spice. Saffron cultivation is believed to have been introduced in Kashmir by Central Asian immigrants around the 1st Century BCE. It is referred to as ‘bahukam’ in ancient Sanskrit literature. It is cultivated and harvested in the Karewa of J&K. Conditions: Altitude: Saffron grows well at an altitude of 2000 meters above sea level. It needs a photoperiod (sunlight) of 12 hours. Soil: It grows in many different soil types but thrives best in calcareous (soil that has calcium carbonate in abundance), humus-rich and well-drained soil with a pH between 6 and 8. Climate: For saffron cultivation, we need an explicit climatological summer and winter with temperatures ranging from no more than 35 or 40 degree Celsius in summer to about –15 or –20 degree Celsius in winter. Rainfall: It also requires adequate rainfall that is 1000-1500 mm per annum.

National Saffron Mission (NSM):

• It was launched in 2010-11 but it was only applicable for the cultivation of saffron in Jammu and Kashmir.
• In 2020, the Government has decided to revive this mission and expand the cultivation of saffron to the north eastern part of the country.
• It comes under the governance of the Ministry of Science and Technology.
• North East Centre For Technology Application and Reach (NECTAR) has been given the charge to manage the pilot project which will be started in the northeast for saffron cultivation.

North East Center For Technology Application and Reach (NECTAR):

• It is an autonomous body under the Department of Science & Technology, Government of India supported a pilot project to explore the feasibility of growing saffron in North East region of India, with the same quality and higher quantity.
• Its headquarters are in Shillong, Meghalaya.

Lithium reserves in J&K

Context:

• The Union Ministry of Mines has announced that lithium reserves had been found in Jammu and Kashmir, a first in the country.

What is Lithium?

• Lithium is a soft, silvery metal. It has the lowest density of all metals.
• Under standard conditions, Lithium is the lightest metal and the lightest solid element. Like all alkali metals, lithium is highly reactive and flammable. It never occurs freely in nature due to its high reactivity.
• Greenbushes mine in Western Australia is the largest hard-rock lithium mine in the world and Australia is the global leader in Lithium production.
• Lithium is primarily extracted from brine pools (‘Salar’ in Chile) and rock minerals such as spodumene (in Australia).

Why is lithium so important?

• Lithium is a key element for new technologies and finds its use in ceramics, glass, telecommunication and aerospace industries.
• It is used in Lithium ion batteries, lubricating grease, high energy additive to rocket propellants, and optical modulators for mobile phones.
• Lithium is used in electric car batteries because of its lightness and energy density.
• It is also used as a convertor to tritium used as a raw material for thermonuclear reactions i.e. fusion.
• The thermonuclear application makes Lithium as “Prescribed substance” under the Atomic Energy Act, 1962.

Helium Reserves

Context:

• Researchers have proposed a new model that could help the world tap into helium reserves to address shortage issues, the study published in Nature journal highlighted.
• Helium—essential for many medical and industrial processes—is in critically short supply worldwide.

What is Helium?

• Helium is a chemical element with the symbol He and atomic number 2.
• It is a noble gas and has a closed-shell electronic configuration, making it stable and unreactive.
• Its boiling point is the lowest among all the elements.
• It is a colourless, odourless, tasteless, non-toxic, inert, monatomic gas, the first in the noble gas group in the periodic table.
• Helium is the second most abundant element in the universe, after hydrogen. However, it is relatively rare on Earth, with most of it being produced by the decay of radioactive elements in the Earth's crust.
• Natural gas is the primary source of helium on Earth.

Applications of Helium:

• Balloons: As already mentioned, the most common use for helium gas is for decorative balloons. However, this has since stretched to helium for weather balloons and airships.
• Medical Applications: Helium gas can be used for respiratory ailments to treat conditions such as asthma and emphysema. Liquid helium also has medical purpose as it is used as a cooling medium for magnets and process use in MRI scanners and NMR spectrometers.
• Car/Vehicles: As helium is a very unreactive element, it is used to detect leaks in car air-conditioning systems. It is also used to inflate airbags as helium can diffuse quicker than most unreactive gases.
• Barcode Scanners: Supermarkets use helium for scanning barcodes at checkouts using helium-neon gas lasers. Helium can be used for lasers because even at high temperatures, the gas will not bond or react with other elements. 
• Deep-Sea Diving: An artificial atmosphere is created using 20% oxygen and 80% helium to keep divers and others who work in pressurised conditions safe. The ability to consistently monitor this artificial atmosphere is something that Analox specialises in.

Helium Reserves in India:

• India’s Rajmahal volcanic basin in Jharkhand is the storehouse of helium trapped for billions of years, since the very birth of Earth from the Sun.
• At present, researchers are mapping the Rajmahal basin extensively for future exploration and harnessing of helium.

CRISP App

Context:

• Recently, the Rubber Board has launched a mobile app CRISP to inform growers about rubber cultivation and provides solutions online.

What is CRISP App?

• The Comprehensive Rubber Information System Platform (CRISP) application has been developed by the Rubber Research Institute of India (RRII) in collaboration with the Digital University of Kerala.
• It gives information to rubber cultivators related to production and productivity enhancement, reduction of cultivation cost, maintenance of soil fertility, disease control measures, etc.

Rubber Plantation:

• Natural rubber is a polymer made up of a chemical molecule called isoprene.
• It is a native of the Amazon basin which was introduced to countries in the tropical belts of Asia and Africa in the late nineteenth century.
• Conditions:
  • Soil: Well-drained, weathered soils.
  • Rainfall: It requires moist and humid climates with heavy rainfall of more than 200 cm.
  • Temperature: It grows well in equatorial climates and temperatures above 25 degrees Celsius.
• In India:
  • India is the world's largest producer and the third largest user of natural rubber and one of the world's fastest expanding economies.
  • Traditional Areas growing areas are: Primarily in Tamil Nadu’s Kanyakumari District and Kerala.
  • Non-traditional regions growing areas are Coastal Karnataka, Goa, Maharashtra’s Konkan Region, coastal Andhra Pradesh and Orissa, the northeastern provinces, and the Andaman and Nicobar Islands, among other places.

Disasters:

SAKURAJIMA VOLCANO

• Context
  • Recently, the Sakurajima Volcano erupted on Japan’s major western island of Kyushu.
  • In 2021, the Fukutoku-Okanoba Submarine Volcano exploded in the Pacific Ocean, off Japan.

• What is Sakurajima Volcano?
  • Sakurajima is one of Japan’s most active volcanoes and eruptions of varying levels take place on a regular basis.
  • It is an active stratovolcano.
  • The largest historical eruptions of Sakurajima took place during 1471-76 and in 1914.
  • Its eruption has been recorded since the 8th Century.
  • Due to its frequent deposition of ash on Kagoshima, and due to its explosive potential, it is considered as one of the very dangerous volcanoes.
• Volcano
  • A volcano is an opening in a planet or moon’s crust through which molten rock, hot gases, and other materials erupt. Volcanoes often form a hill or mountain as layers of rock and ash build up from repeated eruptions.
  • Volcanoes are classified as active, dormant, or extinct. Active volcanoes have a recent history of eruptions; they are likely to erupt again. Dormant volcanoes have not erupted for a very long time but may erupt at a future time. Extinct volcanoes are not expected to erupt in the future.
  • Inside an active volcano is a chamber in which molten rock, called magma, collects. Pressure builds up inside the magma chamber, causing the magma to move through channels in the rock and escape onto the planet’s surface. Once it flows onto the surface the magma is known as lava.
  • Some volcanic eruptions are explosive, while others occur as a slow lava flow. Eruptions can occur through a main opening at the top of the volcano or through vents that form on the sides. The rate and intensity of eruptions, as well as the composition of the magma, determine the shape of the volcano.
  • Volcanoes are found on both land and the ocean floor. When volcanoes erupt on the ocean floor, they often create underwater mountains and mountain ranges as the released lava cools and hardens. Volcanoes on the ocean floor become islands when the mountains become so large they rise above the surface of the ocean.
• Reasons for Magma Rise
• Magma can rise when pieces of Earth's crust called tectonic plates slowly move away from each other. The magma rises to fill in the space. When this happens, underwater volcanoes can form.
• Magma also rises when these tectonic plates move toward each other. When this happens, part of Earth's crust can be forced deep into its interior. The high heat and pressure cause the crust to melt and rise as magma.
• The final way that magma rises is over hot spots. Hot spots are the hot areas inside of Earth. These areas heat up magma. The magma becomes less dense. When it is less dense it rises. Each of the reasons for rising magma are a bit different, but each can form volcanoes.

DERECHO STORM

• Context
  • States of Nebraska, Minnesota and Illinois in the US were recently hit by a storm system called a derecho.
  • As the storm rolled in, winds gusting at around 140 km per hour, snapped power lines and knocked down trees. As the storm hit, it turned the skies green, with even many experienced storm chasers claiming to have never witnessed such atmospheric optics
  • They mostly occur across central and eastern parts of the United States. In 2009 “Super Derecho” was one of the “most intense and unusual derechos ever observed” in the US as it swept from Kansas to Kentucky (US States) with wind speeds reaching up to 170 km/hr.
• What is a Derecho
  • A derecho, according to the US’s National Weather Service is “a widespread, long-lived, straight-line windstorm” that is associated with a “band of rapidly moving showers or thunderstorms”. The name comes from the Spanish word ‘la derecha’ which means ‘straight’. Straight-line storms are those in which thunderstorm winds have no rotation, unlike a tornado. These storms travel hundreds of miles and cover a vast area.
  • Being a warm-weather phenomenon, a derecho generally – not always – occurs during summertime beginning in May, with most hitting in June and July. However, they are a rare occurrence as compared to other storm systems like tornadoes or hurricanes.
  • For a storm to be classified as a derecho it must have wind gusts of at least 93 km per hour; a wind damage swath extends more than 400 km. According to the University of Oklahama’s School of Meteorology, the time gap between successive wind damage events should not be more than three hours.
• Why did the sky turn green during the derecho that hit the US recently
  • Severe thunderstorms result in a ‘green sky’ due to light interacting with the huge amount of water they hold.
  • A report in the Washington Post said that it is believed that the big raindrops and hail scatter away all but the blue wavelengths due to which primarily blue light penetrate below the storm cloud.
  • This blue then combines with the red-yellow of the afternoon or the evening sun to produce green
  • They fall into three categories – progressive, serial and hybrid. A progressive
  • derecho is associated with a short line of thunderstorms that may travel for hundreds of miles along a relatively narrow path. It is a summer phenomenon.
  • A serial derecho, on the other hand, has an extensive squall line – wide and long – sweeping across a large area. It usually occurs during spring or fall.
• Where do derechos usually occur
  • They mostly occur across central and eastern parts of the United States.
  • The May 8, 2009 “Super Derecho” was one of the “most intense and unusual derechos ever observed” in the US as it swept from Kansas to Kentucky with wind speeds reaching up to 170 km/hr.
  • Derechos have also been documented elsewhere across the world. In 2010, Russia witnessed its first documented derecho.
  • They have also swept through Germany and Finland, and more recently in Bulgaria and Poland.

Mapping:

AEGEN SEA

• Context:  Turkey and Greece at odds over islands in the Aegean Sea. Greece and Turkey have had long-standing rival claims over the Aegean territory, even finding themselves on the brink of war over the issue in the past .
• Why is the Aegean Sea at the centre of Greco-Turkish ties?
  • The Aegean Sea, spanning over two lakh square kilometres, is an arm of the Mediterranean Sea.
  • It is located in the East Mediterranian Basin with the Greek peninsula to its west and Anatolia (consisting of the Asian side of Turkey) to its east. There are more than a thousand islands in the Aegean Sea, almost all Greek, and some within two kilometres of mainland Turkey or the Turkish west coast.
  • Greece and Turkey have been regional adversaries on a host of issues concerning the Aegean sea since the 1970s, both asserting rival claims over their borders in the Sea. They came to the brink of war in 1996 over a pair of uninhabited islets in the Aegean Sea, referred to as the Imia islets in Greece and as Kardak in Turkey.
  • A Turkish cargo ship had run aground in Imia in December 1995 and both countries rushed to salvage it.
  • Turkey rejected Greece’s help and its sovereignty over Imia. Shortly after, both countries moved their navies towards Imia, resulting in a standoff that spilled over into January of 1996.
  • The issue attracted international concern as both countries began to mobilise their forces for war, however, global intervention prevented further escalation.

    

 

• What are the issues that have caused friction over the Aegean Sea?
  • Turkey and Greece have long sparred over the extent of their respective territorial waters in the Aegean, the determination of continental shelves, airspace, Exclusive Economic Zones (EEZs), militarisation, and sovereignty of certain islets. 
• Continental shelves and Exclusive Economic Zones
  • In geological terms, the continental shelf is defined as the seabed and subsoil that is the prolongation of a country’s landmass, extending beyond its territorial sea. 
  • The Exclusive Economic Zone (EEZ) is a zone in which a country has special rights to exploration, use of natural resources, wind and hydro-power generation, and other economic activities like laying of pipelines, fishing and so on.
  • As per the UNCLOS, the continental shelf extends to 200 nautical miles from the country’s coastal baseline but is within its continental margin.
  • A country has sovereign rights over the natural resources in the water and the seabed and soil within its continental shelf. EEZs also extend to 200 nm from the coastline. 

SNAKE ISLAND

• Context: Ukraine has said it has caused “significant losses” to the Russian military in airstrikes on Zmiinyi Island, also known as Snake Island, in the Black Sea amidst the ongoing war
  .
• Where is Snake island located
  • Snake Island, also known as Serpent Island or Zmiinyi Island , is an island belonging to Ukraine located in the Black Sea, near the Danube Delta, with an important role in delimiting Ukrainian territorial waters.
  • Snake Island is located 35 km from the coast, east of the mouth of the Danube River. The island's coordinates are 45°15′N 30°12′E. The island is X-shaped, 690 meters from S-W to N-E by 682 meters from N-W to S-E, covering an area of 0.205 km2 (0.079 sq mi).
  • The highest area is 41 metres (135 ft) above sea level. The island does not have a prominently featured mountain, but rather a low-slope hill.
• Lithology of Snake Island
  • The bedrock of the island consists of Silurian and Devonian sedimentary rocks, primarily metamorphosed, highly cemented quartzite conglomerate-breccias, with subordinate conglomerate, sandstone and clay, which form cliffs surrounding the island up to 25 metres high.
  • The structural geology of the island is defined by a wavy monocline orientated to the northeast, with a small anticline in the eastern part of the island.
  • The island is crisscrossed by faults with both N-S and NE-SW orientations.
  • The nearest coastal location to the island is Kubanskyi Island on the Ukrainian part of the Danube Delta, located 35 km (22 mi) away between the Bystroe Channel and Skhidnyi Channel. The closest Romanian coastal city, Sulina, is 45 km (28 mi) away. The closest Ukrainian city is Vylkove, 50 km (31 mi); however, there also is a port Ust-Dunaisk, 44 km (27 mi) away from the island.
• Strategic island.
  • The island, which has been known since ancient times and is marked on the map by the tiny village of Bile that is located on it, belongs to Ukraine.
  • On February 24, the day Russia launched its invasion, two warships from the Russian Black Sea Fleet, Vasily Bykov and Moskva, attacked Snake Island, followed by Russian troops landing on it.
  • Ukraine has claimed to have launched several attacks on the Russian occupiers of Snake Island even before the latest ongoing operation.
  • Ukraine said it had sunk a Russian naval tug called Spasatel Vasily Bekh, which was delivering personnel and military supplies to the island. Earlier in April, it had sunk the Moskva, the 600-foot flagship of the Black Sea Fleet, which had attacked the island on day 1 of the war.
• BLACK SEA
  • The Black Sea is located at the southeastern extremity of Europe. It is bordered by Ukraine to the north, Russia to the northeast, Georgia to the east, Turkey to the south, and Bulgaria and Romania to the west.
  • The roughly oval-shaped Black Sea occupies a large basin strategically situated at the southeastern extremity of Europe but connected to the distant waters of the Atlantic Ocean by the Bosporus (which emerges from the sea’s southwestern corner), the Sea of Marmara, the Dardanelles, the Aegean Sea, and the Mediterranean Sea. The Crimean Peninsula thrusts into the Black Sea from the north, and just to its east the narrow Kerch Strait links the sea to the smaller Sea of Azov.
  • The Black Sea coastline is otherwise fairly regular.
  • The maximum east-west extent of the sea is about 730 miles (1,175 km), and the shortest distance between the tip of Crimea and Cape Kerempe to the south is about 160 miles (260 km). The surface area, excluding the Sea of Marmara but including the Sea of Azov, is about 178,000 square miles (461,000 square km);
  • The Black Sea proper occupies about 163,000 square miles (422,000 square km). A maximum depth of more than 7,250 feet (2,210 metres) is reached in the south-central sector of the sea.

• SALINITY
  • The Black Sea is a saltwater sea, but it is of lesser salinity than the oceans. The salinity of the Black Sea's surface waters averages between 17 and 18 parts per thousand, which is approximately half that of the oceans. A marked increase in salinity, up to 21 parts per thousand, occurs in the Black Sea at depths of roughly 160 to 500 feet (50 to 150 metres).

Swiss Glaciers

Context:

• Switzerland has recorded the worst melt rate of its glaciers since monitoring began more than 100 years ago, losing six per cent of their remaining volume this year or nearly double the previous record of 2003, according to the Swiss Glacier Monitoring Network (GLAMOS).

More about Swiss Glaciers:

• Switzerland is home to around half of all glaciers in the European Alps.
• But the country’s glaciers were reduced by 50 per cent between 1931 and 2016, according to the study. Since 2016, melting has accelerated, and the glaciers have declined by another 12 per cent.
• Not all areas have melted at the same rate. Altitude, debris and glacier shape all affect how quickly the ice retreats.

Why are Swiss Glaciers melting?

• The main and obvious reason is – climate change – a rise in temperature.
• More than half of the glaciers in the Alps are in Switzerland where temperatures are rising by about twice the global average.
• Snowfall replenishes ice lost each summer and helps protect glaciers from further melting by reflecting sunlight back into the atmosphere.
• If greenhouse gas emissions continue to rise, the Alps’ glaciers are expected to lose more than 80 per cent of their current mass by 2100.
• Many will disappear regardless of whatever emissions action is taken now, thanks to global warming baked in by past emissions, according to a 2019 report by the UN Intergovernmental Panel on Climate Change.

What is the largest glacier in Switzerland?

• Aletsch Glacier, the Alps' largest and longest glacier, lying in the Bernese Alps of south-central Switzerland

Alps Mountains:

• The Alps are the highest and most extensive mountain range system that lies entirely in Europe, stretching approximately 1,200 km across seven Alpine countries: France, Switzerland, Italy, Liechtenstein, Austria, Germany, and Slovenia.
• The Alps emerged during the Alpine orogeny, an event that began about 65 million years ago as the Mesozoic Era was drawing to a close.
• The Alps are young fold mountains with rugged relief and high conical peaks.
• The Alps extend in an arc from France in the south and west to Slovenia in the east, and from Monaco in the south to Germany in the north.

THERI DESERT

• Context : 
  • There is a desert in Tamil Nadu and the dunes are red.
  • There are a couple of theories regarding the formation of these dunes, the most plausible being the role of southwest monsoonal winds
• What is the Theri Desert
  • It is a small desert situated in the state of Tamil Nadu.
  • It consists of red sand dunes and is confined to Thoothukudi district.
  • The red dunes are called theri in Tamil.
  • They consist of sediments dating back to the Quaternary Period and are made of marine deposits.
  • They have very low water and nutrient retention capacity.
  • The dunes are susceptible to aerodynamic lift. This is the push that lets something move up. It is the force that is the opposite of weight.
  • The petrographical study (petrography is the study of composition and properties of rocks) and X-ray diffraction analysis (a method used to determine a material’s crystallographic structure) of the red sand dunes reveal the presence of heavy and light minerals.
• Minerals composition include:
  • Ilmenite
  • Magnetite
  • Rutile
  • Garnet
  • Zircon
  • Diopside
  • Tourmaline
  • Hematite
  • Goethite
  • Kyanite
  • Quartz
  • Feldspar
  • Biotite
• The reason why dunes are red coloured
  • The iron-rich heavy minerals like ilmenite, magnetite, garnet, hypersthene and rutile present in the soil had undergone leaching by surface water and were then oxidised because of the favourable semi-arid climatic conditions.
  • It was due to these processes that the dunes near Tiruchendur, a coastal town in Thoothukudi district are red-coloured. 

 

 

• Spread of dunes
  • The dunes are spread over Kuthiraimozhi theri (2,387.12 hectares) and Sathankulam (899.08 ha) reserve forest of Tiruchendur taluk, which is located on the shoreline overlooking the Bay of Bengal in the south-eastern part of Tamil Nadu.
• How did they form?
  • Theris appear as gentle, undulating terrain.
  • The lithology of the area shows that the area might have been a paleo (ancient) coast in the past. The presence of limestone in many places indicates marine transgression.
  • The present-day theris might have been formed by the confinement of beach sand locally, after the regression of the sea.
  • When high-velocity winds from the Western Ghats blew east, they induced migration of sand grains and accumulation of dunes.
  • Another view is that these are geological formations that appeared in a period of a few hundred years.
  • There is a lot of red sand spread over these theris. The red sand is brought from the surface of a broad belt of red loam in the plains of the Nanguneri region (about 57 kilometres from this area in Tirunelveli district) by southwest monsoon winds during May-September.
  • The southwest monsoon winds, after draining the moisture behind the Mahendragiri hill and the Aralvaimozhi gap of the Western Ghats (about 75 kilometres from this area), become dry and strike the plains in the foothills, where vegetation is sparse.
  • Deforestation and the absence of vegetative cover in the Aralvaimozhi gap and the Nanguneri plains are considered to be the major causes of wind erosion.
  • When the dry monsoon wind blows with high velocity, the red loam is churned and driven east in huge columns of red sand, till they are met by sea breeze near the coastal tract of Tiruchendur and get deposited there.
  • The fine materials with light weight are picked up, suspended in the air and carried away. While heavy or large grains are rolled along the ground, grains of intermediate size and weight are carried out at one time and rolled to another.
  • Severe gusts of wind are capable of picking up and carrying materials for short distances and larger materials can be consistently held in the air. Thus, some grains are carried and dropped innumerable times in the course of the history
  • These processes of erosion, transport and deposit of sediments that are caused by wind at or near the surface of the earth, are called Aeolian processes. They lead to continual sand redistribution.
  • The formation of a sand dune is a most characteristic and conspicuous process. When the high-velocity wind blowing sand above the ground meets any obstruction like a fence post, bush, shrub or any other vegetation, the force of the wind is checked and the sand is deposited on the leeward side of the obstruction.
  • The sand deposited thus also forms a further obstruction, causing more sand to be deposited and the process goes on. Thus, in the due course of time, a dune is formed. This is the way a number of sand dunes have been formed over a period of time in Tiruchendur. 
  • The forest department has taken efforts and covered major blocks with vegetation and the movement of sand has been arrested to a considerable extent.

Elaliite and Elkinstantonite

Context:

• A team of researchers in Canada say they have discovered two new minerals – and potentially a third – after analysing a slice of a 15-tonne meteorite that landed in east Africa.
• The meteorite, the ninth largest recorded at over 2 metres wide, was unearthed in Somalia in 2020, although local camel herders say it was well known to them for generations and named Nightfall in their songs and poems.
• Western scientists, however, dubbed the extraterrestrial rock El Ali because it was found near the town of El Ali, in the Hiiraan region. A 70-gram slice of the iron-based meteorite was sent to the University of Alberta’s meteorite collection for classification.

What are Elaliite and Elkinstantonite?

• These are the names given to those two new minerals.
• The minerals have been named “elaliite,” after the town where the meteorite crashed, and “elkinstantonite,” after planetary scientist Lindy Elkins-Tanton.
• Around 4,000 minerals are known to science, and they comprise all the rocks already on Earth. Of those minerals, only about 300 were discovered in meteorites, alien rocks that crashed on Earth.

Great Lakes

Context:

• Scientists are building a sensor network to detect the trends in the water chemistry (acidification process) of Lake Huron, one of the five Great Lakes of North America.
• It is the first step towards developing a system that would be capable of measuring the carbon dioxide and pH levels of the Great Lakes over several years.

What are Great Lakes?

• The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes in the mid-east region of North America that connect to the Atlantic Ocean via the Saint Lawrence River.
• There are five lakes, which are Superior, Michigan, Huron, Erie, and Ontario and are in general on or near the Canada–United States border.

• Hydrologically, lakes Michigan and Huron are a single body joined at the Straits of Mackinac.
• The Great Lakes Waterway enables modern travel and shipping by water among the lakes.
• The Great Lakes are the largest group of freshwater lakes on Earth by total area and are second-largest by total volume, containing 21% of the world's surface fresh water by volume.
• The Great Lakes began to form at the end of the Last Glacial Period around 14,000 years ago, as retreating ice sheets exposed the basins they had carved into the land, which then filled with meltwater.
• The lakes have been a major source for transportation, migration, trade, and fishing, serving as a habitat to many aquatic species in a region with much biodiversity.
• The surrounding region is called the Great Lakes region, which includes the Great Lakes Megalopolis.

Some facts regarding Great Lakes:

• Lake Michigan is the only one of the Great Lakes that is completely within the United States.
• The other four form a natural border between Canada and the United States.
• Lake Superior is the largest and the deepest of the Great Lakes.
• Lake Ontario is the smallest.
• Lake Erie is the shallowest.
• Lake Huron has the longest shoreline.

What is meant by acidification of the water body (lake or ocean)?

• Acidification of oceans or freshwater bodies takes place when excess carbon dioxide in the atmosphere gets rapidly absorbed into them.
• Absorption of carbon dioxide leads to a lowering of the pH, which makes the water bodies more acidic. The pH scale runs from 0 to 14, with 7 being a neutral pH.
• It is known that the increase in atmospheric carbon dioxide has caused the world’s oceans to turn more acidic.
• Recently, it has been observed that by 2100, even the Great Lakes — Superior, Michigan, Huron, Erie, and Ontario — might approach acidity at around the same rate as the oceans.
• That's why reaserchers are measuring CO2 in Great lakes.

Erra Matti Dibbalu

Context:

• Scientists urge Andhra Pradesh govt. to protect glacial-period coastal red sand dunes of Vizag.

What are Erra Matti Dibbalu?

• The city of Visakhapatnam is blessed with a number of sites that have geological importance. One among them is the coastal red sand dunes, popularly known as ‘Erra Matti Dibbalu’.
• Erra Matti Dibbalu is dissected and stabilized coastal red sediment mounds.
• They are formed around 12,000 years ago due to sea-land interaction.
• They comprises a mixture of sand (40-50%), silt and clay (another 50%) with oxidation imparting the unique red colour.

• The site is located along the coast and is about 20 km north-east of Visakhapatnam city and about 4 km south-west of Bheemunipatnam.
• This site was declared as a geo-heritage site by the Geological Survey of India (GSI) in 2014 and the Andhra Pradesh government has listed it under the category of ‘protected sites’ in 2016.

Geological Survey of India (GSI): GSI was set up in 1851 primarily to find coal deposits for the Railways. It is an attached office to the Ministry of Mines. The main functions of the GSI relate to creation and updation of national geo-scientific information and mineral resource assessment. It is headquartered in Kolkata, and has six regional offices located at Lucknow, Jaipur, Nagpur, Hyderabad, Shillong and Kolkata and State Unit offices in almost all States of the country.

Why are they important?

• They are geologically important as they represent the geological history of the late Quaternary period and carry the imprints of the fall of sea level and its subsequent rise, the impact of climate, monsoon and geological processes on the sediments.
• They are anthropologically and archeologically important as they possibly contain mesolithic and neolithic cultural materials as well.

Barak River

Context:

• It was in news due to work related to National Waterway 16.

About Barak River:

• Barak River is the second largest river in the North Eastern Region.
• The Barak River flows 900 kilometres through the states of Manipur, Nagaland, Mizoram and Assam in India.
• It rises in the Manipur hills and enters the plains near Lakhipur, Assam. 
• Further it enters Bangladesh where it bifurcates into the Surma river and the Kushiyara river which converges again to become the Meghna river before forming the Ganges Delta with the Ganga and the Brahmaputra rivers and flowing into the Bay of Bengal.
• Of its length 524 km is in India, 31 km on the Indo–Bangladesh border and the rest is in Bangladesh.
• The upper part of its navigable part is in India — 121 km (75 mi) between Lakhipur and Bhanga, declared as National Waterway 6, (NW-6) since the year 2016.
• The principal tributaries of Barak are the Jiri, the Dhaleswari, the Singla, the Longai, the Sonai and the Katakhal.
• Tipaimukh Dam is a proposed dam on the river itself.

What is National Waterway 16?

• Barak – Meghna river system has a total length of 900 km (origin to upstream Chandpur in Bangladesh).
• Out of this, 524km is in India, 31 km on Indo – Bangladesh border and the rest is in Bangladesh. Out of 524 km in India, 403 km u/s of Lakhipur is in the hilly terrain and it is not navigable.
• The navigable portion of Barak River in India is the 121km stretch between Lakhipur and Bhanga which has been declared as NW-16 in the year 2016.

Geothermal Energy

Context:

• ONGC plans to map the geothermal energy sources of India in search of clean energy.
• Last August, ONGC began drilling in Ladakh in search of geothermal energy sources. But now the company plans to conduct surveys across the country.

What is geothermal energy?

• Geothermal energy is the thermal energy in the Earth's crust which originates from the formation of the planet and from radioactive decay of materials. 
• The high temperature and pressure in Earth's interior cause some rock to melt and solid mantle to behave plastically. 
• Geothermal heating, using water from hot springs, for example, has been used for bathing since Paleolithic times and for space heating since ancient Roman times.
• More recently geothermal power, the term used for the generation of electricity from geothermal energy, has gained in importance.
• It is estimated that the earth's geothermal resources are theoretically more than adequate to supply humanity's energy needs, although only a very small fraction is currently being profitably exploited, often in areas near tectonic plate boundaries.

India and Geothermal Energy:

• According to estimates, India has a potential of 10 GW of geothermal energy.
• The focus on geothermal energy comes at a time when the country has set an ambitious climate target of 500 GW of installed renewable energy capacity and net zero carbon emission by 2070.
• The Geological Survey of India has identified about 340 geothermal hot springs in the country. Most of them are in the low surface temperature range from 370C to 900C, which is suitable for direct heat applications.
• The hot springs in the country are grouped into seven geothermal provinces:
  • Himalayan, Sahara Valley, Cambay Basin, San-Narmada –Topi lineament belt, West Coast, Godavari Basin and Mahanadi Basin.

Puga Project: ONGC is participating to generate electricity through Geothermal Energy at Puga, a remote valley located in Ladakh. Puga Valley is situated in the Changthang Valley in the south-eastern part of Ladakh, about 22 km away from the Salt Lake Valley. It is a region of great significance known for its natural beauty and geothermal activities. It will be India’s first geothermal energy project and also the world’s highest at 14,000ft.

What is ONGC?

• The Oil and Natural Gas Corporation (ONGC) is an Indian central public sector undertaking under the ownership of Ministry of Petroleum and Natural Gas, Government of India.
• It is headquartered in Dehradun. ONGC was founded on 14 August 1956 by the Government of India.
• It is the largest government-owned-oil and gas explorer and producer in the country, and produces around 70% of India's crude oil (equivalent to around 57% of the country's total demand) and around 84% of its natural gas.
• In November 2010, the Government of India conferred the Maharatna status to ONGC.
• ONGC also has accelerated its diversification efforts through its ‘Energy Strategy 2040’.
  • Under the strategy, ONGC targets 5 GW of renewable energy capacity by 2040, with an intermediate target of 2 GW of onshore wind energy and 1.5 GW of solar energy by 2030.

M-Sand Projects

Context:

• Coal India Ltd to launch M-Sand Projects in a big way.

What is Manufactured Sand (M-Sand)?

• M sand is a form of artificial sand, manufactured by crushing large hard stones, mainly rocks or granite, into fine particles, which are then washed and finely graded. It is widely used as a substitute for river sand for construction purposes.

What is M-Sand Project?

• Sand is classified as a “minor mineral”, under The Mines and Minerals (Development and Regulations) Act, 1957 (MMDR Act) and administrative control over minor minerals vests with the State Governments, and accordingly, regulated through State specific rules.
• Due to high demand, regulated supply and complete ban of sand mining during monsoon to protect river ecosystem, finding alternative to river sand became necessary.
• Sand Mining Framework (2018) prepared by Ministry of Mines envisages alternative sources of sand in the form of Manufactured Sand (M-Sand) from crushed rock fines (crusher dust), sand from Overburden (OB) of coal mines.
• During Opencast mining the overlying soil and rocks are removed as waste to extract coal and the fragmented rock (Overburden or OB) is heaped in dumps.
• Most of the waste is disposed off at the surface which occupies considerable land area and requires extensive planning and control to minimize the environmental impact of mining.
• Coal India Ltd (CIL) has envisaged to process the overburden rocks for sand production in mines where OB material contain about 60% sandstone by volume which is harnessed through crushing and processing of Overburden.
• OB to M-Sand initiative of CIL is facilitating processing of waste overburden in its OC Mines. Manufactured Sand (M-Sand) from overburden of coal mines have several benefits in terms of economy and environmental sustainability, including:
  • Cost-effectiveness
  • Consistency
  • Environmental benefits
  • Reduced water consumption
  • Better workability
  • Lesser Sand extraction from river will reduce erosion of channel bed & banks and protect water habitat
  • Help maintaining water table

Indus Water Treaty

Context:

• In a recent notice to Pakistan, India sought modification of the Indus Waters Treaty following Pakistan’s repeated objections to India’s Kishenganga and Ratle hydropower projects in Kashmir.

What Indus Water Treaty, 1960?

• The Indus Water Treaty (IWT) is a water-distribution treaty between India and Pakistan, arranged and negotiated by the World Bank, to use the water available in the Indus River and its tributaries.
• It was signed in Karachi on 19 September 1960 by then Indian Prime Minister Jawaharlal Nehru and then Pakistani president Ayub Khan.
• The Treaty gives control over the waters of
  • the three “eastern rivers” — the Beas, Ravi and Sutlej with a mean annual flow of 41 billion m3 (33 million acre⋅ft) — to India,
  • while control over the waters of the three “western rivers” — the Indus, Chenab and Jhelum with a mean annual flow of 99 billion m3 — to Pakistan.
• India has about 20% of the total water carried by the Indus system while Pakistan has 80%.
• The treaty allows India to use the western river waters for limited irrigation use and unlimited non-consumptive use for such applications as power generation, navigation, floating of property, fish culture, etc.
• It lays down detailed regulations for India in building projects over the western rivers.
• The preamble of the treaty recognises the rights and obligations of each country in the optimum use of water from the Indus system in a spirit of goodwill, friendship and cooperation.
• It also required both the countries to establish a Permanent Indus Commission constituted by permanent commissioners on both sides.

Dispute resolution mechanism as given in the Treaty:

• The IWT also provides a three-step dispute resolution mechanism:
• Step I: under which “Questions” on both sides can be resolved at the Permanent Commission, or can also be taken up at the inter-government level.
• Step II: In case of unresolved questions or “differences” between the countries on water-sharing, such as technical differences, either side can approach the World Bank to appoint a Neutral Expert (NE) to come to a decision.
• Step III: And eventually, if either party is not satisfied with the NE’s decision or in case of “disputes” in the interpretation and extent of the treaty, matters can be referred to a Court of Arbitration.
• IWT does not have a unilateral exit provision and is supposed to remain in force unless both the countries ratify another mutually agreed pact.

New Plateau type Discovered

Context:

• A new plateau type discovered in Maharashtra could prove to be a repository of information to study climate change effects on species survival.

More about the newly discovered plateau:

• A rare low-altitude basalt plateau housing 76 species of plants and shrubs from 24 different families discovered in the Thane region in the Western Ghats—one of the four global biodiversity hotspots in India, can prove to be a repository of information for species interactions.
• It can help study the effects of climate change on species survival and increase awareness of the conservation needs of rock outcrops and their immense biodiversity value in the global context.
• The Western Ghats is one of four global biodiversity hotspots in India, and Agharkar Research Institute (ARI) in Pune has been studying its biodiversity, particularly its rock outcrops, for a decade.
• Plateaus are dominant landscapes in the Western Ghats, significant because of the predominance of endemic species.
• They are classified as a type of rock outcrop and provides unique and challenging environment for species to adapt to.
• These outcrops have seasonal water availability, limited soil and nutrients, making them ideal laboratories to study the effects of climate change on species survival.
• Plateaus are thus a valuable source of insight into how species can survive in extreme conditions.

Rare Dinosaur Eggs found in Narmada Valley

Context:

• A group of Indian researchers found rare cases of fossilised dinosaur eggs — an egg within an egg — among 256 newly discovered eggs from the Narmada Valley.
• The discovery suggests that Titanosaurs — one of the largest dinosaurs to have roamed the Earth — displayed a notable reproductive trait unique to modern-day birds.

More on the news:

• The team discovered 92 nesting sites containing 265 fossilised eggs — measuring 15-17 centimetres in diameter — during field investigations in the Dhar district of Madhya Pradesh between 2017 and 2020.
• This region falls between the easternmost Lameta exposures at Jabalpur in the upper Narmada Valley (central India) and Balasinor in the west in the lower Narmada Valley (western central India), according to the document.
  • Lameta exposure is a sedimentary rock formation known for its dinosaur fossils.
  • These sedimentary rocks are mostly exposed along the Narmada Valley.
  • The fossil records here are largely concealed by Deccan volcanic flows, which prevents their removal by erosion.
• The eggs belonged to six species, suggesting a higher diversity of these extinct giants in India. Further, Titanosaurs buried their eggs in shallow pits, a behaviour seen in modern-day crocodiles.

Narmada River:

• Narmada is the largest west-flowing river of the peninsular region flowing through a rift valley between the Vindhya Range on the north and the Satpura Range on the south.
• It rises from Maikala range near Amarkantak in Madhya Pradesh.
• It drains a large area in Madhya Pradesh besides some areas in the states of Maharashtra and Gujarat.

 

Geophysical Phenomenon:

SUMMER SOLSTICE

• Context: June 21 is the longest day of the year in the Northern Hemisphere
• What is Summer Solstice:
  • The longest day of 2021 for those living north of the Equator is June 21.
  • In technical terms, this day is referred to as the summer solstice, the longest day of the summer season.
  • It occurs when the sun is directly over the Tropic of Cancer, or more specifically right over 23.5 degree north latitude. 

 

• Why do we have summer solstice?
  • Since Earth rotates on its axis, the Northern Hemisphere gets more direct sunlight between March and September over the course of a day, which also means people living in the Northern Hemisphere experience summer during this time.
  • The rest of the year, the Southern Hemisphere gets more sunlight.
  • During the solstice, the Earth’s axis — around which the planet spins, completing one turn each day — is tilted in a way that the North Pole is tipped towards the sun and the South Pole is away from it.
  • Typically, this imaginary axis passes right through the middle of the Earth from top to bottom and is always tilted at 23.5 degree with respect to the sun. Therefore, the solstice, as NASA puts it, is that instant in time when the North Pole points more directly toward the sun than at any other time during the year. Solstice means “sun stands still” in Latin.
• Characteristics of Summer Solstice
  • This day is characterised by a greater amount of energy received from the sun.
  • According to NASA, the amount of incoming energy the Earth received from the sun on this day is 30 per cent higher at the North Pole than at the Equator.
  • The maximum amount of sunlight received by the Northern Hemisphere during this time is usually on June 20, 21 or 22.
  • In contrast, the Southern Hemisphere receives most sunlight on December 21, 22 or 23 when the northern hemisphere has its longest nights– or the winter solstice.
• How many hours of sunlight the northern hemisphere usually gets on Summer Solstice ?
  • The amount of light received by a specific area in the Northern Hemisphere during the summer solstice depends on the latitudinal location of the place.
  • The further north one moves from the equator, the more light one receives during the summer solstice.
  • At the Arctic Circle, the sun never sets during the solstice.
  • Summer solstice does not mean the earliest sunrise or latest sunset
  • Although June 21 will be the longest day of the year, it does not necessarily mean that it brings the earliest sunrise or latest sunset. It depends on the latitudinal location of the country.

Triple Dip La Niña

Context:

• The ongoing La Niña phase of the equatorial Pacific Ocean has just been predicted to persist for at least another six months, making it one of the longest ever La Niña episodes in recorded history.
• It is also only the third episode since 1950 to stretch into a third year. (Triple Dip La Niña)
• This is likely to have wide-ranging implications for weather events across the world in the coming months, and can potentially aggravate both floods and droughts in different regions.

What is La Niña?

• The periodic warming and cooling of surface waters in the equatorial Pacific Ocean — a phenomenon described as El Niño Southern Oscillations, or ENSO — is known to trigger widespread changes in atmospheric conditions, and has a major influence on global weather patterns, including the Indian monsoon.
• La Niña refers to the ENSO phase in which sea-surface temperatures are cooler than normal.
• The warmer phase is known as El Niño.
• As a result of interactions between ocean and wind systems, El Niño and La Niña have almost opposite impacts on weather events.

What is ‘Triple dip’ La Niña?

• El Niño and La Niña episodes typically last for about nine months to a year. They usually develop in the March-June period, and are the strongest during winter (November-January in the northern hemisphere), before weakening or dissipating by March or April of next year.
• Occasionally, however, they continue for much longer periods. In recent years, the El Niño of 2015-16, spread over 19 months, was one of the longest on record, and was dubbed ‘Godzilla’ due to its sustained high intensity.
• The current La Niña episode has already surpassed that in length. Having started in September 2020, it has prevailed for the last 24 months, and looks set to continue for another six months, and has thus been classified as a ‘triple dip’ La Niña.

Difference between El Niño and La Niña:

• El Niño and La Niña events are not mirror images of each other. They differ in length and strength.
• Period and frequency:
  • El Niño episodes occur more frequently and are usually associated with more impactful weather events.
  • La Niña, on the other hand, has a longer run. That is why multi-year La Niña events, those that continue for more than 12 months, are quite common.
  • An El Niño is more likely to be a single-year event.
• According to a recent paper published by Chinese researchers, almost half (six out of 13) of all La Niña events since 1950 have stretched for two years, while three, including the current one, have continued for three years. In contrast, over 75% of El Niño events (15 out of 20) ended within a year. No El Niño has ever stretched into a third year.

Possible impacts of La Niña on India:

• In the Indian context, La Niña is associated with good rainfall during the monsoon season. This is the opposite of El Niño which is known to suppress monsoon rainfall.
• Thus, a continued spell of La Niña could lead to expectation of another year of good, or normal, rainfall during the monsoon. Until now, the monsoon season this year has produced 7% more rain compared to normal. Last year, the seasonal rainfall was almost 100%.

Impacts of La Niña around the globe:

• In most parts of the United States, for example, La Niña is associated with very dry winters.
• In Australia and Indonesia, and generally in the tropical region, La Niña is expected to bring more rainfall.
• The widespread drought in the United States and flooding in eastern Australia this year could have been a result of the prolonged La Niña.
• The excessive rainfall in Pakistan, which is experiencing its worst flooding disaster, can also be blamed in part on La Niña.
• The World Meteorological Organisation (WMO) said the worsening drought in the Horn of Africa and southern United States carried the “hallmarks of La Niña”, as did the “above average rainfall in southeast Asia and Australasia”. It said that the persistence of La Niña was most likely to result in a worsening of the drought in Africa.

Super Typhoon Hinnamnor

Context:

• The strongest tropical storm of 2022, dubbed Super Typhoon ‘Hinnamnor’, has been barrelling across the western Pacific Ocean and is presently hurtling back towards the islands of Japan and South Korea, packing wind speeds of upto 241 kilometres per hour.

About Super Typhoon Hinnamnor:

• It is, till now, the strongest storm of 2022.
• It is the category 5 typhoon – the highest classification on the scale.
• One of the factors contributing to the Super Typhoon rapidly intensifying and expanding is the fact that it has started absorbing other local meteorological systems. Warm tropical waters and other pre-existing meteorological disturbances have led to the system’s escalation.

Read more: Tropical cyclones are becoming more common in the Arabian Sea

Dvorak Technique

Context:

• Recently, the American meteorologist Vernon Dvorak passed away at the age of 100. He was best credited for developing the Dvorak (read as Do-rak) technique in the early 1970s.

What is Dvorak Technique:

• The Dvorak technique (developed between 1969 and 1984 by Vernon Dvorak) is a widely used system to estimate tropical cyclone intensity (which includes tropical depression, tropical storm, and hurricane/typhoon/intense tropical cyclone intensities) based solely on visible and infrared satellite images.
• The Dvorak technique is a method using enhanced Infrared and/or visible satellite imagery to quantitatively estimate the intensity of a tropical system.

What is the principle behind the Dvorak technique:

• The Dvorak technique is based on cloud patterns.
• Cloud patterns in satellite imagery normally show an indication of cyclogenesis before the storm reaches tropical storm intensity.
• From the satellite images thus obtained, the Dvorak technique helps forecasters to do a pattern recognition from the observed structure of the storm, locate its eye and estimate the intensity of the storm.
• The Dvorak technique said to be one of the greatest meteorological innovations, has undergone several advancements since its inception.

What are tropical cyclones:

• A tropical cyclone is a rapidly rotating storm originating over tropical oceans from where it draws the energy to develop.
• It has a low-pressure centre and clouds spiralling towards the eyewall surrounding the “eye”, the central part of the system where the weather is normally calm and free of clouds.
• Its diameter is typically around 200 to 500 km, but can reach 1000 km. A tropical cyclone brings very violent winds, torrential rain, high waves and, in some cases, very destructive storm surges and coastal flooding.
• The winds blow counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.

 

Global Terrestrial Stilling

• Global terrestrial stilling is the decrease of wind speed observed near the Earth's surface (10-meter height) over the last three decades (mainly since the 1980s).
• This slowdown of near-surface terrestrial winds has mainly affected mid-latitude regions of both hemispheres, with a global average reduction of −0.140 m s−1 dec−1 (meters per second per decade) or between 5 and 15% over the past 50 years. With high-latitude (> 75° from the equator) showing increases in both hemispheres.
• In contrast to the observed weakening of winds over continental surfaces, winds have tended to strengthen over ocean regions.
• In the last few years, a break in this terrestrial decrease of wind speed has been detected suggesting a recovery at global scales since 2013

Causes of Global Terrestrial Stilling:

• The exact causes of the global terrestrial stilling are uncertain and has been mainly attributed to two major drivers:
  • (i) changes in large scale atmospheric circulation, and
  • (ii) an increase of surface roughness due to e.g. forest growth, land use changes, and urbanization.

Given climate change, changes in wind speed are currently a potential concern for society, due to their impacts on a wide array of spheres, such as wind power generation, ecohydrological implications for agriculture and hydrology, wind-related hazards and catastrophes, or air quality and human health, among many others.

Pacific Meridional Mode (PMM)

• Pacific Meridional Mode (PMM) is a climate mode in the North Pacific. The mode describes the meridional variability in the tropical Pacific Ocean.
  • Climate Mode or Climate variability includes all the variations in the climate that last longer than individual weather events.

It is similar to the Indian Ocean Dipole. The Indian Ocean Dipole (IOD), also known as the Indian Niño, is an irregular oscillation of sea surface temperatures in which the western Indian Ocean becomes alternately warmer (positive phase) and then colder (negative phase) than the eastern part of the ocean.

• In PMM's positive state, it is characterized by the coupling of weaker trade winds in the northeast Pacific Ocean between Hawaii and Baja California with decreased evaporation over the ocean, thus increasing sea surface temperatures (SST); and the reverse during its negative state.
• This coupling develops during the winter months and spreads southwestward towards the equator and the central and western Pacific during spring, until it reaches the Intertropical Convergence Zone (ITCZ), which tends to shift north in response to a positive PMM.

 

Cloudburst Incidents

Context: Over 20 people have been killed in the destruction caused by cloudbursts and flash floods in different parts of Himachal Pradesh and Uttarakhand over the last three days. Isolated areas in these two states have reported heavy rainfall during this time, triggering landslides and flash floods that have disrupted rail and road traffic, and resulted in house and wall collapses.

What are cloudbursts?

• A cloudburst is a localised but intense rainfall activity. Short spells of very heavy rainfall over a small geographical area can cause widespread destruction, especially in hilly regions where this phenomenon is the most common.
• Not all instances of very heavy rainfall, however, are cloudbursts.
  • A cloudburst has a very specific definition: Rainfall of 10 cm or more in an hour over a roughly 10 km x 10-km area is classified as a cloudburst event.
  • By this definition, 5 cm of rainfall in a half- hour period over the same area would also be categorized as a cloudburst.
• To put this in perspective, in a normal year, India, as a whole, receives about 116 cm of rainfall over the entire year. This means if the entire rainfall everywhere in India during a year was spread evenly over its area, the total accumulated water would be 116 cm high.
  • There are, of course, huge geographical variations in rainfall within the country, and some areas receive over 10 times more than that amount in a year. But on average, any place in India can be expected to receive about 116 cm of rain in a year.
• During a cloudburst event, a place receives about 10% of this annual rainfall within an hour.
  • It is a worse situation than what Mumbai had experienced on July 26, 2005, which is one of the most extreme instances of rainfall in India in recent years.
  • At that time, Mumbai had received 94 cm of rain over a 24-hour period, resulting in deaths of over 400 people and more than USD 1 billion in economic losses.

How common are cloudbursts?

• Cloudbursts are not uncommon events, particularly during the monsoon months.
• Most of these happen in the Himalayan states where the local topology, wind systems, and temperature gradients between the lower and upper atmosphere facilitate the occurrence of such events.
• However, not every event that is described as a cloudburst is actually, by definition, a cloudburst.
• That is because these events are highly localized. They take place in very small areas which are often devoid of rainfall measuring instruments.
• The consequences of these events, however, are not confined to the small areas. Because of the nature of terrain, the heavy rainfall events often trigger landslides and flash floods, causing extensive destruction downstream.
• This is the reason why every sudden downpour that leads to destruction of life and property in the hilly areas gets described as a “cloudburst”, irrespective of whether the amount of rainfall meets the defining criteria. At the same time, it is also possible that actual cloudburst events in remote locations aren’t recorded.

Can cloudbursts be forecasted?

• The India Meteorological Department forecasts rainfall events well in advance, but it does not predict the quantum of rainfall — in fact, no meteorological agency does. The forecasts can be about light, heavy, or very heavy rainfall, but weather scientists do not have the capability to predict exactly how much rain is likely to fall at any given place.
• Additionally, the forecasts are for a relatively large geographical area, usually a region, a state, a meteorological sub-division, or at best a district. As they zoom in over smaller areas, the forecasts get more and more uncertain. Theoretically, it is not impossible to forecast rainfall over a very small area as well, but it requires a very dense network of weather instruments, and computing capabilities that seem unfeasible with current technologies.
• As a result, specific cloudburst events cannot be forecast. No forecast ever mentions a possibility of a cloudburst. But there are warnings for heavy to very heavy rainfall events, and these are routinely forecast four to five days in advance. Possibility of extremely heavy rainfall, which could result in cloudburst kind of situations, are forecast six to 12 hours in advance.

Are cloudburst incidents increasing?

• There is no long-term trend that suggests that cloudbursts, as defined by the IMD, are rising.
• What is well established, however, is that incidents of extreme rainfall, as also other extreme weather events, are increasing — not just in India but across the world. While the overall amount of rainfall in India has not changed substantially, an increasing proportion of rainfall is happening in a short span of time. That means that the wet spells are very wet, and are interspersed with prolonged dry spells even in the rainy season.

Hurricane Storm Surge

Context:

• Hurricane Ian, one of the most violent storms to hit the United States, caused a “500-year flood event” in Florida, due to a strong storm surge.

What is Storm Surge?

• A storm surge is a rise in sea level that occurs during tropical cyclones, typhoons or hurricanes.
• The storms produce strong winds that push the water into shore, which can lead to flooding.
• This surge appears as a gradual rise in the water level as the storm approaches.
• Water level heights during a surge can reach 20 feet or more above normal sea level.

Tsunami vs Storm surge vs Storm tide: A storm surge is not to be confused with a tsunami, because although both events can lead to the formation of huge, destructive waves of water, a tsunami can only be formed by an earthquake or other seismic activity. On the other hand, a storm surge is formed primarily due to the high-velocity winds of a hurricane, and to a lesser extent, low-pressure conditions. It should also not be confused with a storm tide. When a storm surge and high tide combine their forces, it forms an even stronger surge, known as a storm tide.

Formation of storm surge:

• When a hurricane is in deep ocean waters, the circulating wind pushes the ocean surface to create a vertically circulating column of water, where the surge is barely visible.
• However, as the storm moves closer to the shore, the water which is being pushed downwards by the wind cannot move any lower, so the water forces itself from the sides towards land, causing a storm surge wave.
• Whenever a tropical cyclone or hurricane moves near coastal areas, storm surges are the biggest and most common threat to life and property.
• This phenomenon is commonly found in low-pressure systems, and the severity of the storm surge wave depends on the tides, shallowness of the water in the area, and the angle at which the water is to the hurricane.

Cyclone Sitrang

Context:

• Bangladesh has been devastated by Cyclone Sitrang, the first tropical cyclone of the post-monsoon season of 2022.
• It is named by Thailand.

What are tropical cyclones:

• A tropical cyclone is a rapidly rotating storm originating over tropical oceans from where it draws the energy to develop.
• It has a low-pressure centre and clouds spiralling towards the eyewall surrounding the “eye”, the central part of the system where the weather is normally calm and free of clouds.
• Its diameter is typically around 200 to 500 km but can reach 1000 km. A tropical cyclone brings very violent winds, torrential rain, high waves and, in some cases, very destructive storm surges and coastal flooding.
• The winds blow counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.

Cyclone season in India:

• There are mainly two cyclone seasons in India:
  • Pre-monsoon season –  May-June
  • Post-Monsoon Season – October-November
• The Bay of Bengal receives more cyclones as compared to the Arabian Sea. October has seen 61 storms form in the Bay of Bengal over the last 131 years. Whereas the Arabian Sea has only seen 32 storms form in October since 1891.
• But due to climate change frequency of cyclones is also increasing in the Arabian Sea.

Bomb Cyclone

Context:

• Recently, several cities in the USA were hit by a Bomb Cyclone.
• At least 34 people have lost their lives in weather-related incidents across the United States, according to an NBC News tally as the monster storm gripped most of the nation coupled with snow, ice and howling winds, reported Reuters.

What is Bomb Cyclone?

• The term “bomb cyclone” comes from the meteorological term “bombogenesis” or “explosive cyclogenesis.”
• This happens when a storm system's central pressure drops at least 24 millibars within 24 hours.
• A low-pressure system that achieves this mark becomes known as a “bomb cyclone.” Meteorologists also use the phrase “bomb out” to describe the phenomenon.
• The rapid drop in air pressure means the storm intensifies very quickly and can create large impacts such as heavy snow, rain, high winds and coastal flooding.
• Bomb cyclones are more common in the Pacific Ocean but do happen in the Atlantic Ocean.

What is meant by a cyclone? In meteorology, a cyclone is a large air mass that rotates around a strong center of low atmospheric pressure, counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. Cyclones are characterized by inward-spiraling winds that rotate about a zone of low pressure. What are the different types of cyclones? The two main types are the tropical cyclone and the extratropical cyclone. Tropical cyclones: They are violent storms that originate over oceans in tropical areas and move over to the coastal areas bringing about large scale destruction caused by violent winds, very heavy rainfall and storm surges. Tropical cyclones originate and intensify over warm tropical oceans. Extratropical cyclone: They are also called Temperate cyclones or middle latitude cyclones or Frontal cyclones or Wave Cyclones. These are active above the mid-latitudinal region between 35° and 65° latitude in both the hemispheres. The direction of movement is from west to east and more pronounced in the winter seasons. It is in these latitude zones the polar and tropical air masses meet and form fronts. What are the differences between Tropical and Extratropical cyclones: Tropical Cyclones Extratropical cyclones move from east to west. move from west to east has an effect on a comparatively smaller area than a Temperate cyclone. affect a much larger area The velocity of wind in a tropical cyclone is much higher and it is more damaging. The velocity of air is comparatively lower Tropical Cyclone forms only on seas with temperature more than 26-27 degrees C and dissipates on reaching the land. Temperate cyclones can be formed on both land and sea A tropical cyclone doesn’t last for more than 7 days (generally) Temperate cyclone can last for a duration of 15 to 20 days

Do all bomb cyclones forms in the winter?

• Not all bomb cyclones happen in the fall and winter months. A study published in the Journal of Applied Meteorology and Climatology looked at 783 bomb cyclones over 15 years in the Pacific Ocean.
• The study found in 69% of cases, bomb cyclones frequently happened from December to February and early March.
• According to researchers, the frequency depends on the region of the Pacific where the storm is located, with a peak in March and the second peak in October, November and December.

Earth’s Inner Core

Context:

• Earth’s inner core, a hot iron ball the size of Pluto, has stopped spinning faster than the planet’s surface and might now be rotating slower than it, research suggested.

More on the recent study:

• The study published in Nature Geoscience states that the globally consistent pattern suggests that inner-core rotation has recently paused.
• The rotation came to a grinding halt in 2009 and then it surprisingly turned in an opposite direction.
• Researchers have long believed that the inner core rotates, relative to the Earth’s surface, back and forth, like a swing.
• “One cycle of the swing is about seven decades, meaning it changes direction roughly every 35 years. It previously changed direction in the early 1970s, and predicted the next about-face would be in the mid-2040s,” the researcher said.
• The spin of the inner core is driven by the magnetic field generated in the outer core and balanced by the gravitational effects of the mantle. Knowing how the inner core rotates could shed light on how these layers interact and other processes deep in the Earth.

Earth's Inner Core:

• Earth’s layers are divided into three parts: the crust, mantle, and core
• Earth’s inner core was first discovered in 1936 as researchers were studying seismic waves from earthquakes that travel throughout the planet.
• The inner core is solid due to the pressure caused by the weight put on it by the Earth’s other top layers.
• It is distinct from the outer core, which is a liquid.
• Roughly 5,000 kilometers (3,100 miles) below the surface we live on, the inner core can spin independently because it floats in the liquid metal outer core.
• It is predicted to have very high thermal and electrical conductivity.

Joshimath Crisis

Context:

• Joshimath has been in the limelight since the cracks appeared in hundreds of houses in the area.

What is the Joshimath crisis?

• Wide Cracks have appeared on the roads and on hundreds of residential and commercial buildings in the Joshimath town.
• Many structures have been declared unsafe, and the residents have been asked to vacate them.
• The Authorities have declared Joshimath as a landslide and subsidence-hit zone. The whole town is sinking.
• Joshimath is a town situated in Chamoli District of Uttarakhand. It is located in the Middle Himalayas at an altitude of 1875 m.
• Joshimath is a religious and tourist place, and is situated near the holy shrine of Badrinath – one of the Char Dhams in Uttarakhand.
• The Town is situated in a geologically unstable region (Seismic Zone V).
• It is situated north of Main Central Thrust of Himalayas near Tapovan Fault.
• Also the Vaikrita Thrust and Panduksehwar Thrusts are very close to Joshimath.
• Its location near a fault is one of the reasons making it susceptible to subsidence.

Causes for the Joshimath Crisis?

• Anthropogenic causes include:
  • Development Projects: Various development projects are being undertaken nearby the sinking region. These include NTPC’s 520 MW Tapovan-Vishnugad Hydro Power Project and widening of roads under the Char Dham Project.
  • Unbridled Tourism: Unbridled tourism in this ecologically sensitive area has become a cause of trouble for the local environment, which is losing its natural form and being distorted by continuous commercial activities.
  • Unplanned Urbanisation: Most of the buildings have been constructed without proper studies about the underlying soil.
  • Water Withdrawal: Subsidence occurs when large amounts of groundwater are withdrawn from specific types of rocks, such as fine-grained sediments.
  • Absence of Proper Drainage: It leads to landslides. The existence of soak pits, which allow water to slowly soak into the ground, is responsible for the creation of cavities between the soil and the boulders. This leads to water seepage and soil erosion.
• Natural or geomorphological causes include:
  • Joshimath is located in seismic zone V which is more prone to earthquakes besides gradual weathering and water percolation which reduce the cohesive strength of the rocks over time.
  • The Mishra Committee Report states that Joshimath is situated on a sand and stone deposit. A majority of the town has been constructed on the debris of landslides, leading to smooth and eroded rocks and loose soil on the surface.
  • The Mishra Committee Report has also pointed out that subsidence in Joshimath might have been triggered by the reactivation of a geographic fault where the Indian Plate has pushed under the Eurasian Plate along the Himalayas.
  • Undercutting by Alaknanda and Dhauliganga river currents is also contributing to landslides in the region.

Mishra Committee:

• It was appointed by the Central Government almost 50 years ago to look into why Joshimath was sinking.
• It was headed by the then-collector of Garhwal – MC Mishra.
• The report submitted by the 18-member committee clearly explained that Joshimath was situated on an old landslide zone and could sink if development continued unabated, and recommended that construction be prohibited in Joshimath.

Heat Dome

Context:

• At least seven countries in Europe recorded their hottest January weather ever. These included Poland, Denmark, the Czech Republic, the Netherlands, Belarus, Lithuania and Latvia.
• Experts said that the continent is experiencing an extremely warm spell because of the formation of a heat dome over the region.

What is a heat dome?

• A heat dome occurs when an area of high-pressure traps warm air over a region, for an extended period. The longer that air remains trapped, the more the sun works to heat the air, producing warmer conditions with every passing day.

• Heat domes generally stay for a few days but sometimes they can extend up to weeks, which might cause deadly heat waves.
• Moreover, when air sinks, it gets drier and further raises the temperature of the area.
• In 2021, a heat dome formed over western Canada and the US, causing deadly heat waves. Portland city in Oregon, US, saw the mercury rise to 46 degrees Celsius while the temperature in Washington hit 49 degrees Celsius.

Formation of heat domes and jet streams:

• The heat dome’s formation is related to the behaviour of the jet stream; an area of fast-moving air high in the atmosphere.
• The jet stream is believed to have a wave-like pattern that keeps moving from north to south and then north again.
• When these waves get bigger, they move slowly and sometimes can become stationary. This is when a heat dome forms.

Deep-Water Circulations

Context:

• It was in news due to a recently published study regarding the roles of deep water circulation in the global atmosphere.

What is Deep Water Circulation?

• It refers to the movement of water in the deep ocean. It is driven by the density differences between water masses caused by variations in temperature and salinity.
• In the Earth's polar regions ocean water gets very cold, forming sea ice. As a consequence, the surrounding seawater gets saltier, because when sea ice forms, the salt is left behind.
• As the seawater gets saltier, its density increases, and it starts to sink. Surface water is pulled in to replace the sinking water, which in turn eventually becomes cold and salty enough to sink. This creates a circulation pattern that is known as the thermohaline circulation.

Why it is important?

• It helps to distribute heat around the globe, which helps to regulate the Earth's temperature and keep different regions from becoming too hot or too cold.
• It is responsible for shaping the ocean's currents and the circulation patterns of the world's oceans. These currents in turn influence the marine ecosystem, weather patterns, and coastal regions.
• It plays a critical role in controlling atmospheric carbon dioxide levels by helping to transport carbon from the surface to the deep ocean, where it can be stored for long periods of time.

Deep Water circulations and the Indian Ocean:

• The Indian Ocean does not produce its own deep water, it only receives it from other sources such as the North Atlantic and Antarctic.
• The northern part of the Indian Ocean is located far away from the areas where deep water is formed and ocean routes, making it a good place to study the impact of ocean circulation changes
• Studies have been done in the Indian Ocean to understand past Deepwater circulation using records from iron-manganese crusts and authigenic neodymium isotope composition of sediment cores.

Turkey-Syria Earthquake

Context:

• The strongest earthquake in decades in Turkey has caused massive damage, flattening thousands of buildings in the country and neighbouring Syria.
• Within a span of 12 hours, at least 41 more earthquakes of magnitude 4 or more have been recorded in the same area — southeastern Turkey close to the borders with Syria

Geological Causes – The Plate Tectonic

• Turkey lies at the centre of three tectonic plates — Anatolian, Arabian and African.
• The Anatolian Plate is a continental tectonic plate that is separated from the Eurasian plate and the Arabian plate by the North Anatolian Fault and the East Anatolian Fault respectively.
• Most of the country of Turkey is located on the Anatolian plate.
  

  TURKEY, A HOTBED OF SEISMIC ACTIVITY In the Eastern Mediterranean Region comprising Turkey, Syria and Jordan, tectonics are dominated by complex interactions between the African, Arabian, and Eurasian tectonic plates, and the Anatolian tectonic block. Dominant structures here are: Red Sea Rift, the spreading centre between the African and Arabian plates; Dead Sea Transform, a major strike-slip fault that also accommodates Africa-Arabia relative motions; North Anatolia Fault, a right-lateral strike-slip structure in northern Turkey accommodating much of the translational motion of the Anatolia block westwards with respect to Eurasia and Africa; Cyprian Arc, a convergent boundary between the African plate and the Anatolia block.

• The movement of the tectonic plates builds up pressure on fault zones at their boundaries.
  • Faults are cracks in the earth’s crust along which there is movement. These can be massive (the boundaries between the tectonic plates themselves) or very small.
  • It is the sudden release of this pressure that causes earthquakes and ground shaking.
• The Turkey earthquake is likely to have happened on one of the major faults — the East Anatolian fault or the Dead Sea Transform fault.
• Earthquake energy is actually caused by movement along an area of a fault. These are called as “strike-slip quake”
  • The bigger the earthquake, the larger the fault area that will have moved.
  • For a 7.8 magnitude, there is likely to have been a movement over an area roughly 190 km long and 25 km wide.

Strike-slip quake: This is an earthquake caused by a strike-slip fault. It is caused when two tectonic plates slide past one another horizontally instead of vertically. When two tectonic plates happen to go sliding past each other sideways instead of up and down, it is called a strike-slip quake. In a strike-slip earthquake, as the plates push against each other on a vertical fault line, stress builds up until one of the plates slips horizontally. This releases a tremendous amount of strain which can result in an earthquake. One of the most famous strike-slip faults is the San Andreas Fault in California in the US. In the case of the turkey quake, one block moved east while the other went west. As they ground past each other as one slip, it caused an extremely powerful and devastating earthquake.

• This means the shaking will be felt over an extensive area.
• Light shaking was felt by about 610,000 people as far away as Istanbul (around 815 km away), as well as Baghdad in Iraq (800 km) and Cairo in Egypt (950 km).
• After major earthquakes, there will be many smaller earthquakes known as aftershocks as the crust readjusts to the changes in stress.
• In the first 12 hours after the initial tremor in southeast Turkey. there were already three other earthquakes above magnitude 6.0.
• A magnitude 7.5 aftershock occurred further to the north on a different but adjacent fault system: the Sürgü Fault which was powerful enough to count as a separate earthquake in its own right.
• While aftershocks are usually significantly smaller than the main shock, they can have equally devastating consequences, further damaging infrastructure that was damaged by the first earthquake and hampering rescue efforts.

Why did Turkey suffer such extensive damage to life and property?

The magnitude and intensity of the earthquake:

• The energy from an earthquake travels through Earth in vibrations called seismic waves. Scientists can measure these seismic waves on instruments called seismometers.
• The earthquake events are scaled either according to the magnitude or intensity of the shock.
  • The magnitude scale is known as the Richter scale. The magnitude relates to the energy released during the quake. The magnitude is expressed in absolute numbers, 0-10.
  • The intensity scale is named after Mercalli, an Italian seismologist. The intensity scale takes into account the visible damage caused by the event. The range of intensity scale is from 1-12.

• The magnitude of the earthquakes that struck Turkey was 7.8 with 6.7 aftershocks.
• An earthquake this size (7.8 magnitude) has the potential to be damaging anywhere in the world.

The shallow nature of the Turkey earthquakes:

• The earthquakes are divided into three zones: shallow, intermediate, and deep based on their depth which ranges between 0 – 700 km.
  • Shallow earthquakes have a focus 0 – 70 km deep.
  • Intermediate earthquakes have a focus 70 – 300 km deep.
  • Deep earthquakes have a focus 300 – 700 km deep.
• Turkey’s earthquakes emerged from relatively shallow depths which made them devastating.
  • The first earthquake, of magnitude 7.8, originated 17.9 km below the Earth’s surface.
  • All the subsequent ones, including one of 7.5 magnitudes, emerged from even closer to the surface.
• Shallow earthquakes are generally more devastating because they carry greater energy when they emerge on the surface.
• Deeper earthquakes lose much of their energy by the time they come to the surface. The deeper quakes spread farther though — the seismic waves move conically upwards to the surface — even as they lose energy while travelling greater distances, and hence cause less damage.

Lack of earthquake-resistant buildings in Turkey:

• This area has a lot of structures that are highly susceptible to damage from earthquakes that are stronger than 6.0.
• The earthquake brought down at least 6,000 buildings across the 10 provinces of Turkey, including hospitals and other public premises.

A new ocean may arise as Africa continues to split into two parts

Context:

• Scientists, in 2020, predicted a new ocean would be created as Africa gradually splits into two separate parts.
• There is an ongoing geological activity in Africa that has resulted in the gradual separation of the continent into two parts over millions of years.
• This process is known as continental rifting and is caused by the movements of tectonic plates beneath the Earth’s surface.

Ten interesting things about the African continent Africa is the second-largest continent on Earth, covering an area of about 30.2 million square kilometers. There are 54 recognized countries in Africa, making it the only continent with so many countries. The Sahara Desert, located in northern Africa, is the largest hot desert in the world, covering an area of about 3.6 million square miles. The Nile River, which flows through Egypt and several other African countries, is the longest river in the world, with a length of about 6,650 kilometers. Africa is home to the largest land mammal, the African elephant, and the fastest land mammal, the cheetah. Mount Kilimanjaro, located in Tanzania, is the highest mountain in Africa and the highest free-standing mountain in the world, with a height of 5,895 meters. The Great Rift Valley located in Eastern Africa, which runs through several African countries, is the largest geological formation on Earth and is home to many unique plant and animal species. Africa has a rich cultural heritage, with over 3,000 distinct ethnic groups and more than 2,000 languages spoken. The continent has a rapidly growing population, with over 1.2 billion people living in Africa, making it the second most populous continent after Asia. Africa is also blessed with many natural resources, including Oil, Gas, Diamonds, Copper, Uranium, Nickle, Aluminium, Bauxite, Coal, Silver and Gold.

More on the news:

• Rifting refers to the geological process in which a single tectonic plate is split into two or more plates separated by divergent plate boundaries.
  • It leads to the emergence of a lowland region known as a rift valley, which can occur either on land or at the bottom of the ocean.
  • These rift valleys occur due to the movement of Earth’s tectonic plates.
• In the case of Africa, three plates — the Nubian African Plate, Somalian African Plate and Arabian Plate — are separating at different speeds.
• The Arabian Plate is moving away from Africa at a rate of about an inch per year, while the two African plates are separating even slower.
• As the Somali and Nubian tectonic plates continue to pull apart from each other, a smaller continent will be created from the rift, which will include present-day Somalia and parts of Kenya, Ethiopia, and Tanzania.
• This new ocean will result in East Africa becoming a separate small continent with its own unique geographic and ecological characteristics.

Vernal Equinox

Context:

• The vernal equinox is observed on March 21st 2023.

What is Equinox?

• A solar equinox is a moment in time when the Sun crosses the Earth's equator, which is to say, appears directly above the equator, rather than north or south of the equator.
• On the day of the equinox, the Sun appears to rise “due east” and set “due west”.
• This occurs twice each year, around 20 March and 23 September.
• In the Northern Hemisphere, the March equinox is called the vernal or spring equinox while the September equinox is called the autumnal or fall equinox. In the Southern Hemisphere, the reverse is true.
• Hemisphere-neutral names are northward equinox for the March equinox, indicating that at that moment the solar declination is crossing the celestial equator in a northward direction, and southward equinox for the September equinox, indicating that at that moment the solar declination is crossing the celestial equator in a southward direction.
• According to Hindu astrology, Vernal Equinox is known as Vasant Vishuva or Vasant Sampat. The Spring equinox brings earlier sunrises, later sunsets, and sprouting plants in the northern hemisphere.
• As a result of Equinox, the Sun is located directly above the equator, and both hemispheres receive an almost equal amount of sunlight.

Atmospheric Rivers

Context:

• Recently, California has experienced an exceptionally wet winter with 11 atmospheric rivers battering the state and a twelfth such storm threatening to cause even more flooding, landslides and road closures.

What are Atmospheric rivers?

• Atmospheric rivers are large, narrow sections of the Earth’s atmosphere that carry moisture from the Earth’s tropics near the equator to the poles.
• On average, the Earth has four to five active atmospheric rivers at any time. They carry massive amounts of moisture. Each moves the equivalent of the liquid water that flows through the mouth of the Amazon River.
• When they reach land, atmospheric rivers release this moisture, producing heavy snow and rain.
• Atmospheric rivers are an important part of the Earth’s climate.
  • They are responsible for 90 percent of the movement of moisture from the tropics toward the poles.
  • This means atmospheric rivers are a major factor in the formation of clouds and therefore have a significant influence on air temperatures, sea ice, and other components of the climate.
• Moisture from atmospheric rivers shapes large parts of the world.
• Research indicates that they are responsible for more than half of the rainfall in parts of the coasts of North America, France, Spain, Portugal, the United Kingdom, South America, Southeast Asia, and New Zealand.
• As such, they are critical to plant and animal life, agriculture, and people as sources of water. But atmospheric rivers can also cause severe flooding due to the massive amounts of precipitation they release.

Western Disturbances

Context:

• Recently large parts of the country experienced hailstorms which were also accompanied by torrents of rain.

What are Western Disturbances?

• A western disturbance is an extra tropical storm originating in the Mediterranean region that brings sudden winter rain to the northern parts of the Indian subcontinent, which extends as east as up to northern parts of Bangladesh and South eastern Nepal.
• It is a non-monsoonal precipitation pattern driven by the westerlies. The moisture in these storms usually originates over the Mediterranean Sea, the Caspian Sea and the Black Sea.
• Extra tropical storms are a global phenomenon with moisture usually carried in the upper atmosphere, unlike their tropical counterparts where the moisture is carried in the lower atmosphere.
• In the case of the Indian subcontinent, moisture is sometimes shed as rain when the storm system encounters the Himalayas. Western disturbances are more frequent and stronger in the winter season.

Formation of Western disturbances:

• Western Disturbance (WD) is an extra-tropical storm which originates in the Mediterranean region,
• A high-pressure is exhibited area over the areas like Russia and neighbourhood countries causes the intrusion of cold air from Polar Regions towards an area of relatively warmer air with high moisture.
• This change in pressure from cold air to warm air generates favourable conditions for cyclogenesis in the upper layer of the atmosphere, which promotes the formation of an eastward-moving extra tropical depression in the sea.
• In the term “extra-tropical storm”, storm refers to low pressure. “Extra-tropical” means outside the tropics. As the WD originates outside the tropical region, the word “extra-tropical” has been associated with them.
• Then these gradually travel across the middle-east from Iran, Afghanistan, and Pakistan to finally enter the Indian sub-continent.

Significance of Western disturbances:

• Western disturbances, specifically the ones in winter, bring moderate to heavy rain in low-lying areas and heavy snow to mountainous areas of the Indian Subcontinent.
• They are the cause of most winter and post-monsoon season rainfall across northwest India.
• Precipitation during the winter season has great importance in agriculture, particularly for the rabi crops.
• Wheat among them is one of the most important crops, which helps to meet India's food security. An average of four to five western disturbances form during the winter season.
• The rainfall distribution and amount varies with every western disturbance.
• Western disturbances are usually associated with cloudy sky, higher night temperatures and unusual rain.
• Impact of Western disturbances:
  • Excessive precipitation due to western disturbances can cause crop damage, landslides, floods and avalanches.
  • Dense fog is already being witnessed in the plains of northern India. As the western disturbance will be bringing more moisture, there will be an increase in fog. Low visibility problems will increase in Delhi-NCR, Uttar Pradesh, Punjab and Haryana.
  • The strongest western disturbances usually occur in the northern parts of Pakistan, where flooding is reported number of times during the winter season.
  • Weak western disturbances are associated with crop failure and water problems across north India.

Geomagnetic Storms

Context:

• There was some discussion about the potential effects of geomagnetic storms on the global communication system.

What are Geomagnetic Storms?

• A geomagnetic storm, also known as a magnetic storm, is a temporary disturbance of the Earth's magnetosphere caused by a solar wind shock wave and/or cloud of the magnetic field that interacts with the Earth's magnetic field.

• A geomagnetic storm is a major disturbance of Earth's magnetosphere that occurs when there is a very efficient exchange of energy from the solar wind into the space environment surrounding Earth. These storms result from variations in the solar wind that produces major changes in the currents, plasmas, and fields in Earth’s magnetosphere.
• The solar wind conditions that are effective for creating geomagnetic storms are sustained (for several to many hours) periods of high-speed solar wind, and most importantly, a southward directed solar wind magnetic field (opposite the direction of Earth’s field) at the dayside of the magnetosphere. This condition is effective for transferring energy from the solar wind into Earth’s magnetosphere.
• The largest storms that result from these conditions are associated with solar coronal mass ejections (CMEs) where a billion tons or so of plasma from the sun, with its embedded magnetic field, arrives at Earth. CMEs typically take several days to arrive at Earth, but have been observed, for some of the most intense storms, to arrive in as short as 18 hours.
• Another solar wind disturbance that creates conditions favorable to geomagnetic storms is a high-speed solar wind stream (HSS). HSSs plow into the slower solar wind in front and create co-rotating interaction regions, or CIRs. These regions are often related to geomagnetic storms that while less intense than CME storms, often can deposit more energy in Earth’s magnetosphere over a longer interval.
• 
• Storms also result in intense currents in the magnetosphere, changes in the radiation belts and changes in the ionosphere, including heating the ionosphere and upper atmosphere region called the thermosphere.

Geomagnetic storm effects: Infographics

A Monster Monsoon caused a massive Pakistan Flood

Context: While Europe, China and some other regions of the world are experiencing a severe drought, Pakistan is facing one of the worst floods in its recent history. Reports say about 110 of the 150 districts in the country are affected by the flooding.

What is the immediate cause of the flood?

• The current flood is a direct result of an extremely wet monsoon season this year. The same southwest monsoon that brings the bulk of India’s annual rainfall causes rain in Pakistan as well.
• The monsoon season in Pakistan, however, is a little shorter than in India. That is because the rain-bearing monsoon winds take time to travel northward from India into Pakistan.
  • The official monsoon season in Pakistan begins on July 1 and extends until September, although most of the rainfall happens during the months of July and August.
  • The active rainfall season is only one and a half months.
• The normal rainfall for Pakistan as a whole during this three-month monsoon season is 140 mm, according to PMD. But because the season is quite short, there is a wide variation in the monsoon rainfall every year.
• This year, the country saw plenty of rain from late June itself. But August has been exceptionally wet. Minister Rehman shared PMD data that showed until Friday, August had produced two and a half times its normal rainfall — 176.8 mm against the expected 50.4 mm.
• In Sindh, it has rained almost eight times the normal amount during this period; Balochistan has received over five times more.

What are the long-term causes of floods?

• The climate crisis is the prime suspect for the devastating scale of flooding in Pakistan.
• Scientists are already trying to determine the extent to which global heating is to blame for the rainfall and floods. But analysis of the previous worst flood in 2010 suggests it will be significant. That “superflood” was made more likely by global heating, which drove fiercer rains.
• Warmer oceans and heating in the Arctic were implicated in the 2010 superflood, one study found, as these factors affected the jet stream, a high-level wind that circles the planet. The greater meandering of the jet stream led to both the prolonged rain in Pakistan and an extreme heatwave in Russia that year.
• And according to a 2021 study global heating is making the south Asian monsoon more intense and more erratic, with each 1C rise in global temperature leading to 5% more rain.

Extreme Weather Events

Context:

• The Centre for Science and Environment (CSE) and Down to Earth recently published a report, India 2022: An Assessment of Extreme Weather Events, on the extreme weather events in India.

What are Extreme weather events?

• The UN Intergovernmental Panel on Climate Change (IPCC) defines extreme weather events as those that are “rare at a particular place and time of year”.
• While India does not have an official definition, the India Meteorological Department (IMD), in its annual “Statement of Climate of India” reports, classifies lightning and thunderstorm, heavy to very and extremely heavy rainfall, landslide and floods, cold wave, heat wave, cyclones, snowfall, dust and sandstorms, squalls, hailstorms and gales as extreme weather events.
• The agency has defined each of these weather events under its website “Climate Hazards and Vulnerability Atlas of India”, launched in January 2022, and in its other publications.
• The CSE and Down to Earth compiled records of such extreme weather events in India between January 1 and September 30 this year, as maintained by the IMD and the Disaster Management Division (DMD) under the Union Ministry of Home Affairs.
• Along with this report, Down To Earth has also launched India’s Atlas on Weather Disasters, an online public interactive database on extreme weather events that would be updated every month.

What are the report's highlights?

• The data revealed that India witnessed extreme weather events on 241 out of 273 days in 2022.
• This means that India has experienced a disaster “nearly every day in the first nine months of this year”, ranging from heat waves, cyclones, and lightning, to heavy rain, floods and landslides.
• The country recorded its warmest March, and the third warmest April, in over a century.
• Madhya Pradesh witnessed the highest number of days with extreme weather events, with such events occurring every second day in the state.
• As many as 2,755 people lost their lives to such extreme weather events across India.
• Assam and Madhya Pradesh both lost 301 people to extreme weather events. However, Himachal Pradesh saw the highest number of human deaths, at 359.
• Assam reported the highest number of damaged houses and animal deaths.
• The central and north-western regions reported the highest number of days with extreme weather events at 198 and 195, respectively. In terms of human lives lost, central India topped the list with 887 deaths, followed by the east and northeast (783 deaths).
• In 2022, India recorded its seventh wettest January since 1901. This March was also the warmest ever and the third driest in 121 years. It was also the country’s third warmest April, 11th warmest August and 8th warmest September since 1901.
• Eastern and northeastern India saw its warmest and driest July in 121 years. The region also recorded its second warmest August and fourth warmest September in 2022.

About the Centre for Science and Environment (CSE):

• Centre for Science and Environment (CSE) is a public interest research and advocacy organisation based in New Delhi.
• CSE researches into, lobbies for and communicates the urgency of development that is both sustainable and equitable.

Mauna Loa

• The largest active volcano in the world, ‘Mauna Loa’ in Hawaii shows indications that it could erupt.
• Mauna Loa is one of five volcanoes that together make up the Big Island, the southernmost island of the Hawaiian archipelago.
• Mauna Loa is the largest volcano and makes up about half of the island’s land mass.
• Mauna Loa volcano last erupted 38 years ago in 1984.
• Hawaii’s volcanoes are called shield volcanoes because successive lava flows over hundreds of thousands of years build broad mountains that resemble the shape of a warrior’s shield.

Beaver Blood Moon

Context:

• Recently a rare spectacle of a ‘Beaver Blood Moon’ happened over the night skies of East Asia to North America.

What is Beaver Blood Moon:

• It is simply a type of total lunar eclipse. It is named Beaver Blood Moon because it is taking place in the month of November and it is a total lunar eclipse.

• This will be the last time the Earth, moon and sun align to produce a total lunar eclipse till 2025.
• The full beaver moon was visible across North America, the Pacific, Australia and East Asia, while it was also visible for a short duration in Indian cities including Kolkata and Guwahati.
• Total lunar eclipses occur, on average, about once every year and a half, according to NASA.
• But the interval varies. Tuesday’s event will mark the second blood moon this year, following one in mid-May. The next one is not expected until March 14, 2025.
• November’s Beaver Full Blood Moon Is The Longest Lunar Eclipse In A Century.

What are Moon Eclipses/lunar eclipses?

• Lunar eclipses happen when Earth positions itself between the sun and the moon, casting a shadow across the lunar surface.
• They can only occur during a full moon and are a popular event for skywatchers worldwide as they do not require any specialist equipment to enjoy (unlike solar eclipses).
• There are three types of lunar eclipses depending on how the sun, Earth and moon are aligned at the time of the event.
  • Total lunar eclipse: Earth's shadow is cast across the entire lunar surface.
  • Partial lunar eclipse: During a partial lunar eclipse, only part of the moon enters Earth's shadow, which may look like it is taking a “bite” out of the lunar surface. Earth's shadow will appear dark on the side of the moon facing Earth. How much of a “bite” we see depends on how the sun, Earth and moon align, according to NASA (opens in new tab).
  • Penumbral lunar eclipse: The faint outer part of Earth's shadow is cast across the lunar surface. This type of eclipse is not as dramatic as the other two and can be difficult to see. 

• During a total lunar eclipse, the lunar surface turns a rusty red color, earning the nickname “blood moon”. The eerie red appearance is caused by sunlight interacting with Earth's atmosphere.
• In 2023, Earth will experience two lunar eclipses.

Solar Eclipse: A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby obscuring Earth's view of the Sun, totally or partially. There are 4 different types of solar eclipses. How much of the Sun's disk is eclipsed, the eclipse magnitude, depends on which part of the Moon's shadow falls on Earth. Partial solar eclipses occur when the Moon only partially obscures the Sun's disk and casts only its penumbra on Earth. Annular solar eclipses take place when the Moon's disk is not big enough to cover the entire disk of the Sun, and the Sun's outer edges remain visible to form a ring of fire in the sky. An annular eclipse of the Sun takes place when the Moon is near apogee, and the Moon's antumbra falls on Earth. Total solar eclipses happen when the Moon completely covers the Sun, and it can only take place when the Moon is near perigee, the point of the Moon's orbit closest to Earth. You can only see a total solar eclipse if you're in the path where the Moon casts its darkest shadow, the umbra. Hybrid Solar Eclipses, also known as annular-total eclipses, are the rarest type. They occur when the same eclipse changes from an annular to a total solar eclipse, and/or vice versa, along the eclipse's path.

Europe’s Great Drought

Context: Europe is facing its worst drought in at least 500 years, with two-thirds of the continent in a state of alert or warning, reducing inland shipping, electricity production and the yields of certain crops, a European Union agency said.

How severe this drought is?

• The drought has been billed as the worst in 500 years. It is being said that never has a European summer been so dry since 1540, when a year-long drought killed tens of thousands of people. The dry spell this year follows a record-breaking heatwave that saw temperatures in many countries rise to historic highs.
• The impact has been debilitating. Water transport has suffered badly, and is having cascading effects. Power production has been hit, leading to electricity shortages and a further increase in energy prices already pushed high by the war in Ukraine. Food is sharply more expensive in many countries, and drinking water is being rationed in some regions.
• An “analytical report” of the Global Drought Observatory (GDO), an agency of the European Commission, released on Tuesday said about 64% of the continent’s landmass was experiencing drought conditions, as per data available till August 10. And the situation was only “worsening” as of that date, it said.
• Nearly 90% of the geographical area in Switzerland and France, about 83% in Germany, and close to 75% in Italy, was facing agricultural drought. Some areas, especially the UK, have received rain in the last one week, but it has made only a marginal difference to the overall situation.

Pileus Cloud

Context: A unique phenomenon showing colourful iridescence formed on a pileus cloud appeared in Puning City in south China's Guangdong Province. At first glance it looks like a rainbow, but it's actually a cloud.

What is Pileus Cloud?

• A pileus, also called scarf cloud or cap cloud, is a small, horizontal, lenticular cloud appearing above a cumulus or cumulonimbus cloud. Pileus clouds are often short-lived, with the main cloud beneath them rising through convection to absorb them.
• They are formed by strong updraft at lower altitudes, acting upon moist air above, causing the air to cool to its dew point.
• As such, they are usually indicators of severe weather, and a pileus found atop a cumulus cloud often foreshadows transformation into a cumulonimbus cloud, as it indicates a strong updraft within the cloud

What is iridescent pileus cloud?

• Iridescent pileus clouds are caused by particularly tiny ice crystals or water droplets in the air. Larger ice crystals produce lunar or solar halos, but tiny ice crystals or water droplets cause light to be diffracted – spread out – creating this rainbow-like effect in the clouds.
• Pileus clouds are often short-lived, with the main cloud beneath them rising through convection to absorb them. They are formed by strong updraft at lower altitudes, acting upon moist air above, causing the air to cool to its dew point.
• The clouds must be very thin and made of ice crystals or water droplets of uniform size. So cloud iridescence usually happens in lenticular or alto-cumulus, cirrus and cirrocumulus clouds.

Environment Geography:

RESIDUAL FLOOD DAMAGE UNDER INTENSIVE ADAPTATION

• Context
  • According to the study, Residual Flood Damage under Intensive Adaptation, the risk of river flooding is expected to increase with climate change and socioeconomic development, and therefore additional protection measures are required to reduce the potential for increased flood damage
• What is Residual Flood Management Under Intensive Adaptation
  • RFD ‘refers to unavoidable increases in flood damage even under an adaptation strategy based on feasible adaptation costs’.
  • Adaptation strategy — in the context of floods — implies infrastructural measures that have been employed to mitigate the risks posed by floods.

• Findings of the study
  • Assam will need 943 years of flood protection measures to prevent a crisis like the one it is witnessing if its pace of preparedness and climate adaptation doesn’t increase, according to a new study. 
  • The Indo-Gangetic Plain (excluding West Bengal and Assam) and Meghalaya are most susceptible to future floods in India and need to employ flood protection for the next 875-1,000 years.
  • The Indo-Gangetic Plain (including the Indus and Ganga basins) here includes the states and Union territories of Jammu, Kashmir and Ladakh, Punjab, Uttar Pradesh and Bihar.
  • The northeastern state has always been flood-prone.
  • In 2022, the flooding started as early as May, with 62 per cent above average rainfall from March-May —  a 10-year high.
  • Other flood-prone states like Bihar, Uttar Pradesh and Meghalaya will need 966, 935 & 996 years respectively.
  • Currently, 33 of Assam’s 35 districts have been affected due to flooding along the Brahmaputra basin, according to the Assam State Disaster Management Authority.
  • Over 4.2 million people have been affected by floods this year, while over 100,000 hectares of cropland have been damaged as of June 20.
  • In this context, mitigating future flood risks becomes important.
  • According to the study’s estimate, RFD in South Asia is estimated to be around $4 million (around Rs 31 crore) and adaptive costs around $3 million.
  • RFD (as a part of the gross domestic product) remained high in eastern China, northern parts of India and the central regions of the African continent, according to the analysis carried out by the researchers.
  • In India, riverine floods — considered one of the major natural disasters — have become synonymous with economic losses. The total flood-related losses in the country were estimated to be over Rs 37 lakh crores from 1953-2017, according to the Central Water Commission.
• Central Water Commission
  • CWC is apex Technical Organization of India in the field of Water Resources.
  • It is presently functioning as an attached office of Union Ministry of Water Resources, River Development and Ganga Rejuvenation.
  • It is charged with the general responsibilities of initiating and coordinating schemes of control, utilization and conservation of water resources throughout the country.
  • These schemes are meant for purpose of Flood Control, Irrigation, Navigation, Drinking Water Supply and Water Power Development.
  • It also undertakes the investigations, construction and execution of any such schemes as required.
  • The work of the Commission is divided among 3 wings namely :
  • River Management Wing (RM),
  • Designs and Research Wing (D&R) and
  • Water Planning and Projects Wing (WP&P).
  • It monitors and prepares monthly reports on the state of glacial lakes and waterbodies measuring 10 hectares and above via satellite.

ECO SENSITIVE ZONES

• Context: The Supreme Court has ordered the establishment of 1-km Eco-Sensitive Zones around all protected areas, wildlife sanctuaries and national parks.
  
  
• What are Eco-Sensitive Zones
  • As per the National Wildlife Action Plan (2002-2016), issued by the Union Ministry of Environment, Forest and Climate Change, land within 10 km of the boundaries of national parks and wildlife sanctuaries are to be notified as eco-fragile zones or Eco-Sensitive Zones (ESZ).
  • While the 10-km rule is implemented as a general principle, the extent of its application can vary. Areas beyond 10 km can also be notified by the Union government as ESZs, if they hold larger ecologically important “sensitive corridors.”
• Significance of ESZs
  • According to the guidelines issued by the Environment Ministry, ESZs are created as “shock absorbers” for the protected areas, to minimize the negative impact on the “fragile ecosystems” by certain human activities taking place nearby.
  • Furthermore, these areas are meant to act as a transition zone from areas requiring higher protection to those requiring lesser protection.
  • The guidelines also state that the ESZs are not meant to hamper the daily activities of people living in the vicinity, but are meant to guard the protected areas and “refine the environment around them”.
• Permitted and Prohibited Activities 
  • The guidelines list the activities prohibited in an ESZ, such as commercial mining, sawmills, commercial use of wood, etc., apart from regulated activities like the felling of trees.
  • Lastly, there are permitted activities like ongoing agricultural or horticultural practices, rainwater harvesting, and organic farming, among others.
• Farmers protest in Kerela
  • Farmers in Kerala continue to protest across several high ranges of the state against the Supreme Court’s recent order to establish 1-km Eco-Sensitive Zones around all protected areas, wildlife sanctuaries and national parks.
• Reasons of Protest
  • The widespread unrest, which has hit districts like Idukki, Kottayam, Pathanamthitta and Wayanad, is borne out of the fear of farmers losing their livelihood and has found support from the state government, opposition parties and the Catholic Church.
  • On June 18, almost two weeks after the court order, the Union government said that it will hold discussions with the Kerala government and file an affidavit in the Supreme Court on the matter.
• What is the recent SC judgment that has caused an uproar in Kerala?
  • On June 3, a three-judge bench of the Supreme Court heard a PIL which sought to protect forest lands in the Nilgiris in Tamil Nadu but was later expanded to cover the entire country.
  • In its judgment, the court while referring to the 2011 guidelines as “reasonable”, as reported by Live Law, directed all states to have a mandatory 1-km ESZ from the demarcated boundaries of every protected forest land, national park and wildlife sanctuary.
  • It also stated that no new permanent structure or mining will be permitted within the ESZ.
  • If the existing ESZ goes beyond the 1-km buffer zone or if any statutory instrument prescribes a higher limit, then such extended boundary shall prevail, the court, as per the Live Law report, said.
• Why are people protesting against it?
  • Protests erupted across the high ranges of Kerala in response to the apex court’s directions. Due to the high density of human population near the notified protected areas, farmer’s groups and political parties have been demanding that all human settlements be exempt from the ESZ ruling.
  • Alex Ozhukayil, the chairman of the Kerala Independent Farmers’ Association (KIFA) claimed that the court’s decision would severely impact the livelihoods of farmers.
  • The Kerala state government had proposed that for some national parks, such as the Thattekad Bird Sanctuary, the extent of the ESZ area should be reduced from the proposed uniform 1 km, to an ESZ ranging from zero to 1 km on the eastern and south-eastern side of the national park.
  • This was because the villagers occupying the densely populated settlements in these areas believed that the ESZ would restrict their agricultural and related activities.
• Have similar protests taken place before in Kerala?
  • This is not the first time that Kerala has faced such protests. In 2013, hartals first erupted in Idukki and Wayanad after the Kasturirangan committee report recommended that 60,000 km of the Western Ghats, covering 12 of Kerala’s 14 districts, be notified as ecologically sensitive areas.
• Similar protests had taken place in Karnataka as well.
  • In December 2021, Karnataka Chief Minister Basavaraj Bommai said he opposed the decision to declare the Western Ghats as an ecologically sensitive zone because it would “adversely affect the livelihood of the people in the region”.

CORAL REEFS

• Context: Four new corals were recorded from Indian waters.
• Findings
  • Scientists have recorded four species of azooxanthellate corals for the first time from Indian waters.
  • These new corals were found from the waters of Andaman and Nicobar Islands.
  • Azooxanthellate corals are a group of corals that do not contain zooxanthellae and derive nourishment not from the sun but from capturing different forms of plankton.
  • These groups of corals are deep-sea representatives, with the majority of species reporting from between 200 m to 1000 m. Their occurrences are also reported from shallow coastal waters.
  • Zooxanthellate corals, meanwhile, are restricted to shallow waters.
  • Tamal Mondal, the Zoological Survey of India (ZSI) scientist behind these new records, said that all the four groups of corals are from the same family Flabellidae.
  • Truncatoflabellum crassum (Milne Edwards and Haime, 1848), T. incrustatum (Cairns, 1989), T. aculeatum (Milne Edwards and Haime, 1848), and T. irregulare (Semper, 1872) under the family Flabellidae were previously found from Japan to the Philippines and Australian waters while only T. crassum was reported within the range of Indo-West Pacific distribution including the Gulf of Aden and the Persian Gulf.
• Significance of findings
  • Azooxanthellate corals are a group of hard corals and the four new records are not only solitary but have a highly compressed skeletal structure.
  • The most studies of hard corals in India have been concentrated on reef-building corals while much is not known about non-reef-building corals. These new records enhance our knowledge about non-reef-building, solitary corals.
  • “Zoological Survey of India has given special emphasis on the exploration of the coastal and marine biodiversity of India in recent times and come out with several new discoveries and ecological findings with utmost importance ”
  • Dhriti Banerjee, director of ZSI, said that coral reefs are one of the most productive, sustainable and pristine ecosystems of the world’s oceans, especially in shallow coastal waters. “These habitats contribute several services associated with human needs and existence. Hard corals are the prime and intrinsic part of the coral reef ecosystem.”
• CORALS DISTRIBUTION IN INDIA
  • There are about 570 species of hard corals found in India and almost 90% of them are found in the waters surrounding Andaman and Nicobar Islands. The pristine and oldest ecosystem of corals share less than 1% of the earth’s surface but they provide a home to nearly 25% of marine life.
  • Four species of azooxanthellate corals were recorded for the first time from the waters of Andaman and Nicobar Islands.
  • India with its coastline of 7,517 km and subtropical climatic conditions has coral reef areas along its coastline and islands.
  • All the three major reef types, atoll, fringing, and barrier, occur in India.
  • In India, Coral reefs are present in the areas of Gulf of Kutch, Gulf of Mannar, Andaman & Nicobar, Lakshadweep Islands, and Malva.
  • The Gulf of Kutch in the northwest, which has some of the most northerly reefs in the world) and Palk Bay and the Gulf of Mannar in the southeast.
  • Coral patches are found in Ratnagiri, Malvan, and Redi, south of Bombay and at the Gaveshani Bank, west of Mangalore.
  • Corals along the shore are found at Quilon on the Kerala coast to Enayem in Tamilnadu.
  • Corals also occur on the east coast between Parangipettai (Porto Novo), south of Cuddalore, and Pondicherry.
  • Among island corals, in Andaman and Nicobar Islands (Fringing and barrier) and Lakshadweep (Atolls) corals are found.

NATURAL FARMING

• Context
  • The government is pushing natural farming across India, without the use of chemical fertilisers and pesticides.
  • Recently, Prime Minister Addressed a Natural Farming Conclave, where he urged farmers to take up Natural Farming.
• What is Natural Farming
  • India became food secure by using high yielding varieties of seeds, fertilisers to nourish the soil and pesticides to keep crop damage at bay. But this was accompanied with environmental damage through overuse of fertilisers, and impacted human and ecological health.
  • Due to the impact of the Green Revolution, “heightened further” by the pandemic, “there is an urgent need to scale up alternative approaches” of farming, wrote economist Mihir Shah, in a January 2022 report in the journal Ecology, Economy and Society.
  • In December 2021, during a conclave on natural farming, Prime Minister Narendra Modi emphasised the need for working on alternative methods of farming, while acknowledging the importance of chemicals and fertilisers in the Green Revolution. “We have to take our agriculture out of the lab of chemistry and connect it to the lab of nature,” he said.
  • This refers to agroecology, which guides public policies towards sustainable agriculture and food systems, according to the Food and Agriculture Organization (FAO). While there is no specific set of practices that are classified as agroecological, it includes those methods that maintain and enhance natural processes related to soil, water and climate in agricultural production, reduce the use of purchased inputs, like fossil fuels and agrochemicals, and create resilient agroecosystems, noted a 2019 High Level Panel of Experts for Food Security and Nutrition (HLPE) of the FAO. These methods focus on promoting crop diversification, restoring and rebuilding natural cycles in the soil, and reducing water demand, among others.
  • Natural farming and organic farming, both come under agroecological practices and are terms used interchangeably in India. In natural farming the focus is on the use of bio inputs prepared from farm and local ecosystems instead of purchasing those from outside. “Organic farming is defined now more from a perspective of product certification. Except for such certification, organic and natural farming in India are largely similar,”.
  • What binds organic and natural farming proponents “is the thrust on the absence of application of chemical fertilisers or chemical pesticides during cultivation”. In organic farming, farmers might use “external agricultural inputs” such as rock phosphate, biopesticides and biofertilisers”.
  • “But [some] natural farming proponents argue that even these external applications are not required, as the farm itself can generate much of the inputs required,” he said, adding that, “therefore, they call it Zero-Budget Natural Farming.”
  • Zero-Budget Natural Farming is one of the many methods of natural farming, popularised by agriculturist Subash Palekar (later known as Subash Palekar Natural Farming).
  • According to the approach, a concoction of natural inputs like cow urine and dung, jaggery, lime, neem among others are used to improve soil health, nutrients and reduce input costs, among other benefits.
  • In July 2022, the government announced that it would constitute a committee to “promote zero-budget based farming, to change crop pattern keeping in mind the changing needs of the country, and to make MSP [Minimum Support Price] more effective and transparent…”. On natural farming the committee will make suggestions for programmes for value chain development, strategies to introduce natural farming curriculum in universities and suggest farmer-friendly alternative certification systems for natural farm produce.

• Is natural farming better than 'Conventional' farming
  • Various state governments have supported organic farming as an alternative farming option in the last few decades. But there are debates worldwide on the impact on crop yield by transitioning to agroecological farming methods and discarding conventional practices that use chemical inputs, especially where soils are nutrient-deficient.
  • If biofertilisers, rhizobium and acetobacter can fix soil health to an extent, there is no need for heavy chemical use, said Ramanjaneyulu. This would also help the government cut spending on fertiliser subsidies, which cost Rs 1.4 lakh crore ($18.7 billion) in 2021-22 and are estimated to cost Rs 1.1 lakh crore ($14.7 billion) in 2022-23, which could rise to Rs 2.5 lakh crore due to higher import prices.
  • But compared to 'conventional farming', according to a 2019 ICAR-National Academy of Agricultural Research Management report, “organic products are usually 3-4 times more expensive due to higher labour cost, certification costs, handling costs and comparatively lower yields”.
  • The jury is still out on which method or which combination of methods would be the best for crop yields. There are knowledge gaps on comparing relative yields and performance of different agroecological practices, according to the HLPE report.
  • “..out of the 504 times that yield results were recorded during 2014–19, 41% of the times yields were highest with organic approach, followed by 33% with integrated and 26% with inorganic approach,” said the February 2022 CSE report that analysed the All India Network Project on Organic Farming (AI-NPOF) of the Indian Council of Agriculture Research and other scientific studies. It reported evidence of highest net returns and best soil health under the organic approach in study centres.
  • “There is scientific evidence on the benefits of natural farming, but the government has to take the initiative to formally collate like it did under AI-NPOF,” said Vineet Kumar, deputy programme manager of Sustainable Food Systems at CSE.
  • On the other hand, the 2019 NAAS report highlighted that studies initiated by the Indian Council of Agriculture Research-Indian Institute of Farming System Research “clearly indicated that yield levels were drastically reduced in rice-wheat cropping system by 59% in wheat and 32% in basmati rice” when tenets of zero-budget natural farming were followed. It further showed a three-year natural farming experiment that showed “a yield decline” in crops tested which “established that food security will be seriously challenged along with farmers' income, if ZBNF [Zero Budget Natural Farming] is adopted”.
  • There is concern that yields will fall with natural farming because 59% of soils in India are deficient in nitrogen, 49% are low in phosphorus and 48% are low in potassium, said Ramakumar. “Organic or ZBNF methods do not replenish enough nutrients in the soils as much as the plants uptake them every season.”
  • Organic and natural farming can be scaled up only to a level, because of several reasons. These include a lack of a national action plan to promote organic and natural farming, dependence on expensive certification for organic produce, which smaller farmers cannot afford, inadequate funding, target-driven and timeline-based policies for natural farming, among others.
• What is the Significance of Natural Farming?
  • Minimized Cost of Production
    • It is considered as a cost- effective farming practice with scope for raising employment and rural development.
  • Ensures Better Health
    • As Natural Farming does not use any synthetic chemicals, health risks and hazards are eliminated. The food has higher nutrition density and therefore offers better health benefits.
  • Employment Generation
    • It generates employment on account of natural farming input enterprises, value addition, marketing in local areas, etc. The surplus from natural farming is invested in the village itself.
    • As it has the potential to generate employment, thereby stemming the migration of rural youth.
  • Environment Conservation
    • It ensures better soil biology, improved agrobiodiversity and a more judicious usage of water with much smaller carbon and nitrogen footprints.
  • Livestock Sustainability
    • The integration of livestock in the farming system plays an important role in Natural farming and helps in restoring the ecosystem. Eco Friendly bio-inputs, such as Jivamrit and Beejamrit, are prepared from cow dung and urine, and other natural products.
  • Resilience
    • The changes in soil structure with the help of organic carbon, no/low tillage and plant diversity are supporting plant growth even under extreme situations like severe droughts and withstanding severe flood and wind damage during cyclones.
    • NF impacts many farmers positively by imparting resilience to the crops against weather extremities.

GREEN PROTECTION TO ARAVALLI

• Context
  • Supreme Court of India has extended the green protection to forest land in Aravalli ranges recently.
• Supreme Court Ruling
  • The Court held that all land covered by the special orders issued under Section 4 of the Punjab Land Preservation Act (PLPA) in Haryana will be treated as forests and be entitled to protection under the 1980 Forest Conservation Act.
  • Special orders under Section 4 of PLPA are the restrictive provisions issued by the state government to prevent deforestation of a specified area that could lead to soil erosion.
  • A bench, headed by justice AM Khanwilkar, shot down the Haryana government’s contention that PLPA has no connection with forests, and that the consequences of connecting the two would be disastrous because it would result in demolition of every building in 11 districts of Haryana, including Gurugram and Faridabad.
  • Terming the submissions “misleading and fallacious”, the bench held that the land covered by the special orders issued under Section 4 of PLPA have all the trappings of forest lands within the meaning of Section 2 of the Forest Act. 
  • It further underlined that once a land is covered under Section 2 of the Forest Act, whether the special orders under Section 4 continue to be in force or not, it shall continue to remain forest land.
  • The court’s ruling will mean around 30,000 hectares across the Aravallis and Shivaliks in Haryana will be considered forest land. “ 
  • Reading the two provisions together, the top court ruled that the rationale behind issuance of special orders under Section 4 of PLPA makes it clear that such areas must be protected as forest.
  • Section 2 of the Forest Act imposes prohibitions on the de-reservation of forests or use of forest land for non-forest purposes without prior approval of the central government.
  • The  bench said that when the state government is satisfied that deforestation of a forest area forming part of a larger area is likely to lead to erosion of soil, the power under Section 4 can be exercised. 
  • Therefore, it follows that the specific land in respect of which a special order under Section 4 of PLPA has been issued will have all the trappings of a forest governed by the Forest Act.
  • It noted that while the land notified under the special orders of Section 4 of PLPA shall be forest lands, not all land under PLPA will ipso facto become forest lands within the meaning of the Forest Act.
• Aravalli Range
  • The Aravallis of Northwestern India, one of the oldest fold mountains of the world, now form residual mountains with an elevation of 300m. to 900m. 
  • They stretch for a distance of 800 km. from Himmatnagar in Gujarat to Delhi, spanning Haryana, Rajasthan, Gujarat, and Delhi, the 692 kilometre (km).
  • The Aravalli range is very rich in natural resources and gave rise to numerous peninsula rivers like Banas, Luni, Sakhi, and Sabarmati.
  • Guru Shikhar is the highest point in the range which is located in Mount Abu.
  • The Aravallis date back to millions of years when a pre-Indian subcontinent collided with the mainland Eurasian Plate.

• Their Significance
• Checks Desertification
  • The Aravallis act as a barrier between the fertile plains in the east and the sandy desert in the west.
  • Historically, it is said that the Aravalli range checked the spread of the Thar desert towards the Indo-Gangetic plains, serving as a catchment of rivers and plains.
• Rich in Biodiversity
  • Provides habitat to 300 native plant species, 120 bird species and many exclusive animals like the jackal and mongoose.
• Impacts Climate
  • Aravallis have an impact upon the climate of northwest India and beyond.
  • During monsoons, it provides a barrier and monsoon clouds move eastwards towards Shimla and Nainital, thus helping nurture the sub-Himalayan rivers and feeding the north Indian plains.
  • In the winter months, it protects the fertile alluvial river valleys from the cold westerly winds from Central Asia.

RAMSAR SITES

• Context
  •  India adds 11 more wetlands to the list of Ramsar sites to make total 75 Ramsar sites covering an area of 13,26,677 ha in the country in the 75th year of Independence.  
• Newly Added Sites
  • The 11 new sites include Four (4) sites in Tamil Nadu, Three (3) in Odisha, Two (2) in Jammu & Kashmir and One (1) each in Madhya Pradesh and Maharashtra. Designation of these sites would help in conservation and management of wetlands and wise use of their resources.  
  • India is one of the Contracting Parties to Ramsar Convention, signed in Ramsar, Iran, in 1971. India signed it on 1st Feb 1982. During 1982 to 2013, a total of 26 sites were added to the list of Ramsar sites, however, during 2014 to 2022, the country has added 49 new wetlands to the list of Ramsar sites.  
  • During this year itself (2022) a total of 28 sites have been declared as Ramsar sites. Based on the date of designation mentioned on Ramsar Certificate, the number is 19 for this year (2022) and 14 for previous year (2021). 
  • Tamil Nadu has maximum no. of Ramsar sites (14 nos), followed by UP which has 10 nos. of Ramsar sites.
      
• SUMMARY OF NEW RAMSAR SITES
  • Tampara Lake
    • Tampara Lake is among the most prominent freshwater lakes in the State of Odisha situated in Ganjam district. The depression on the ground gradually filled with rainwater from catchment flow and was called “Tamp” by the British and subsequently termed “Tampra” by the locals.  The wetland supports at least 60 species of birds, 46 species of fishes, at least 48 species of phytoplanktons, and more than seven species of terrestrial plants and macrophytes. The wetland is an important habitat for vulnerable species such as Cyprinus carpio, common pochard (Aythya ferina), and river tern (Sterna aurantia). With an estimated average fish yield of 12 tonnes per year, the wetland is an important source of livelihood for the local communities. Along with fishes the wetland also provides provisioning services like water for agriculture, and domestic use and is a well-known tourism and recreation site.

      

  • Hirakud Reservoir
  • Hrakud Reservoir, the largest earthen dam in Odisha started operating in 1957. The reservoir to support a range of floral and faunal species, including several of high conservation significance. Out of the known 54 species of fish from the reservoir, one has been classed as being endangered, six near threatened and 21 fish species of economic importance. Fisheries presently yield a catch of around 480 MT of fish annually and is the mainstay of livelihoods of 7,000 fisher households. Similarly, over 130 bird species have been recorded at this site, out of which 20 species are of high conservation significance. The reservoir is a source of water for producing around 300 MW of hydropower and irrigating 436,000 ha of cultural command area. The wetland also provides important hydrological services by moderating floods in the Mahanadi delta, the ecological and socio-economic hub of the east coast of India. Hirakud reservoir supports abundant tourism, and forms an integral part of the high touristic value sites located around Sambalpur with over 30,000 tourists annually visiting the site.

    

  • Ansupa Lake
  • Ansupa Lake is the largest freshwater lake of Odisha situated in Banki sub-division of Cuttack district and has its fame from time immemorial for its scenic beauty, biodiversity, and natural resources. The wetland is an oxbow lake formed by River Mahanadi and is spread over an area of 231 ha. The wetland is home to at least 194 species of birds, 61 species of fishes and 26 species of mammals in addition to 244 species of macrophytes. The wetland provides a safe habitat to at least three threatened bird species- Rynchops albicollis (EN), Sterna acuticauda (EN) and Sterna aurantia (VU) and three threatened fish species- Clarias magur (Clariidae) (EN), Cyprinus carpio (Cyprinidae) (VU) and Wallago attu (VU). Ansupa lake sustains the freshwater demands of the surrounding areas and also supports the livelihood of the local communities through fisheries and agriculture. The wetland has immense recreational and tourism potential as it is a major wintering ground for migratory birds and is also known for its scenic beauty.

  

• • Yashwant Sagar
    • Yashwant Sagar is one of the two Important Bird Areas (IBA) in the Indore region as well as one of the most important birding sites in Malwa region of Madhya Pradesh.  Presently it is mainly used for water supply to the city of Indore and is also being used for fish culture on a commercial scale.  Yashwant Sagar reservoir comes under the jurisdiction of Indore City Municipal Corporation. Indore which has bagged the title of one of the cleanest cities in India is also often known as center of economic growth of Madhya Pradesh. The catchment area of this wetland is predominantly agriculture. Yashwant Sagar is considered to be a stronghold of the vulnerable Sarus Crane in central India. The lake backwaters have plenty of shallow areas, conducive for waders and other waterfowl. As the water level recedes, many islands serve as roosting sites for waterfowl. Due to its vast shallow reed beds, the wetland is considered heaven to a large number of winter migratory birds.
  • Chitrangudi Bird Sanctuary
  • Chitrangudi Bird Sanctuary, locally known as “Chitrangudi Kanmoli” is located in Ramanathapuram district in Tamil Nadu. The wetland is a protected area since 1989 and declared as Bird Sanctuary, coming under the jurisdiction of Tamil Nadu Forest Department, Ramanathapuram division. Chitrangudi Bird Sanctuary is an ideal habitat for winter migratory birds. Around 50 birds belonging to 30 families have been reported from the site.  Out of these 47 are water birds and 3 terrestrial birds. Notable waterbirds spotted from the site area spot-billed pelican, little egret, grey heron, large egret, open billed stork, purple, and pond herons.  Chitrangudi is surrounded by agricultural fields, where different crops are grown throughout the year. The wetland also supports a number of fishes, amphibians, molluscs, aquatic insects, and their larvae forming good food sources for arriving waterbirds. Groundwater is extracted for irrigation around and within the wetland for agricultural purposes.
  •   Suchindram Theroor Wetland Complex
  • Suchindrum Theroor Wetland complex is part of the Suchindrum-Theroor Manakudi Conservation Reserve. It is declared an Important Bird Area and lies at the southern tip of the Central Asian flyway of migratory birds.  It was formed for birds' nesting purposes and it attracts thousands of birds every year. The total population dependent upon Theroor is about 10,500 and 75% of the population’s livelihood hinges on agriculture which in turn is dependent upon the water released from the Theroor tank. This is a man-made, inland Tank and is perennial. Copper plate inscriptions from the 9th century mention Pasumkulam, Venchikulam, Nedumarthukulam, Perumkulam, Elemchikulam and Konadunkulam. Around 250 species of birds have been recorded in the area, of which 53 are migratory, 12 endemic, and 4 threatened.
  • Vaduvur Bird Sanctuary
  • Vaduvur bird sanctuary spreads over an area of 112.638 ha, is a large human-made irrigation tank and shelter for migratory birds as it provides a suitable environment for food, shelter, and breeding ground. While these irrigation tanks have socio-economic and cultural significance, very little is known of their ecological importance. These tanks have the potential to harbor good populations of resident and wintering water birds but no studies have been done to confirm this. Indian Pond Heron Ardeola grayii occurred in most of the surveyed tanks. Large concentrations of wintering waterfowl such as Eurasian Wigeon Anas penelope, Northern Pintail Anas acuta, Garganey Anas querquedula were recorded in tanks. Vaduvur Bird Sanctuary has a diverse habitat including a number of inlets and surrounding irrigated agricultural fields which provides good nesting and foraging habitats for birds. Thus, the site provides support to the species listed above during critical stages of their life-cycle.
  • Kanjirankulam Bird Sanctuary
  • Kanjirankulam Bird Sanctuary is a Protected area near Mudukulathur Ramanathapuram District, Tamil Nadu. India, declared in 1989. It is notable as a nesting site for several migratory heron species that roost in the prominent growth of babul trees there. The breeding population of migratory waterbirds arrive here between October and February and include: painted stork, white ibis, black ibis, little egret, great egret. The site qualifies as an IBA as the threatened Spot-billed Pelican Pelecanus philippensis breeds here.  The wetland exhibits rich biodiversity including many globally near-threatened species like Spot-billed Pelican, Oriental Darter, Oriental white Ibis and Painted Stork and also commonly occurring shore and water birds like greenshank, plovers, stilts and forest birds like bee-eaters, bulbuls, cuckoos, starlings, barbets, etc. They act as breeding, nesting, roosting, foraging, and stopover sites for the birdsThe wetland supports IUCN RedList vulnerable avian species like Sterna aurantia (River Tern).
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  • Thane Creek
  • Thane Creek is located in Maharashtra, India. There are several sources of fresh water to the creek, of which Ulhas River is the largest, followed by many drainage channels from various suburban areas of Mumbai, Navi Mumbai & Thane. It has been declared as Thane Creek Flamingo Sanctuary. Thane creek is fringed by mangroves on both banks & comprises around 20% of the total Indian mangrove species. The mangrove forest acts as a natural shelter belt & protects the land from cyclones, tidal surges, seawater seepage & intrusions. The mangrove serves as a nursery for several fishes & sustains the local fishery. The area is an important part of the wetland complex of the Central Asian Flyway of the birds and has been categorized as an Important Bird Area (IBA). Other than 202 avifaunal species, the creek also houses 18 species of fishes, crustaceans & molluscs, 59 species of butterflies, 67 species of Insects, and 35 species of phytoplankton, and 24 species of zooplankton & 23 species of Benthos.
     
  • Hygam Wetland Conservation Reserve
    • Hygam Wetland falls within the River Jhelum basin and plays a significant role as a flood absorption basin, biodiversity conservation site, eco-tourism site, and livelihood security for the local communities. The wetland is located in the Baramulla district. It serves as an abode to many residents and migratory bird species. It is also recognized as an Important Bird Area (IBA). Consequent to the high rate of siltation, Hygam Wetland has lost its wetland characteristics to a large extent and in many places changed its profile into a landmass. This has resulted in further loss of habitat conditions to offer a suitable site for visiting migratory birds (Winter/ Summer migrants) and for resident birds as well. Hygam Wetland provides a plethora of ecosystem services, these include fish and fiber, water supply, water purification, climate regulation, flood regulation, and recreational opportunities. The livelihoods of people living in, and adjoining the fringes of wetlands depend partially or entirely on wetland ecosystem services.
  • Shallbugh Wetland Conservation Reserve
  • Shallabug Wetland Conservation Reserve is located in the District Srinagar, UT of J&K. Large areas of the wetland dry up between September and March. The area has extensive reedbeds of Phragmites communis and Typha angustata, and rich growth of Nymphaea candida and N. stellata on open water. It serves as an abode to more than four lakh resident and migratory birds of at least 21 species. Shallabugh Wetland plays a major role in the natural control, amelioration or prevention of flooding, It is also important for seasonal water retention for wetlands or other areas of conservation importance downstream. The wetland is important for the recharge of aquifers. A major natural floodplain system. Shallabugh Wetland provides plethora of ecosystem services, these include fish and fiber, water supply, water purification, climate regulation, flood regulation, recreational opportunities. The wetland serves as an important breeding ground for many species of waterbirds.

 

Miscellaneous:

BEDTI-VARADA PROJECT

• Context: Recently, environmental groups in Karnataka have criticised the project to link the Bedti and Varada rivers in Karnataka, calling it ‘unscientific’ and a ‘waste of public money. 
• What is Bedti-Varada project?
  • The project was envisaged in 1992 as one to supply drinking water by the then government.
  • The plan aims to link the Bedti, a river flowing west into the Arabian Sea, with the Varada, a tributary of the Tungabhadra river, which flows into the Krishna, which in turn flows into the Bay of Bengal.
  • The Bedti is known as Gangavali in the estuary region.
  • A massive dam will be erected at Hirevadatti in Gadag district under the project. A second dam will be built on the Pattanahalla river at Menasagoda in Sirsi, Uttara Kannada district.
  • Both dams will take water to the Varada via tunnels of length 6.3 kilometres and 2.2-km.
  • The water will reach at a place called Kengre. It will then go down a 6.88 km tunnel to Hakkalumane, where it will join the Varada.
  • The project thus envisages taking water from the water surplus Sirsi-Yellapura region of Uttara Kannada district to the arid Raichur, Gadag and Koppal districts.
  • A total of 302 million cubic metres of water from Pattanahalla and Shalmalahalla tributaries of the Bedti and Varada rivers, while 222 million cubic metres of water will be drawn from the barrage at Suremane built against the Bedti river.
• Problem associated with the project
  • It is claimed that over 500 acres of forests will be lost. 
  • It is also claimed that both rivers do not have so much water to feed three districts for both domestic and farming purposes. 
  • It would need 61 megawatts of power to pull the water all the way to Gadag. It is difficult to redirect a westward-flowing river to flow eastward. In February, which is early summer, the Bedti and Varada rivers begin to dry up.
  • In addition, flora and fauna will also suffer due to this project. The Bedti valley has been designated as an active biodiversity zone by the International Union for Conservation of Nature(IUCN).
  • The area is home to 1,741 types of flowering plants as well as 420 species of birds and animals.
  • It would affect the nutrients that the river carries with it are responsible for sustaining fish stocks, especially in the Bedti’s estuary in Dedi.