SPR 2022 | Geography Current Affairs Compilation for Prelims 2022

Please Share with maximum friends to support the Initiative.





Weather Phenomena

Western Disturbances

Context:

  • Lack of Western Disturbances in the months of March and April has led to the highest temperatures in last 72 years over Northern India.

About:

  • Last year, one after the other there were many western disturbances. But this year, the western disturbance activity is rare and feeble.
  • Even if it is there, it is moving northward and has not been affecting northwest India.

Western Disturbances:

  • Western Disturbances develop in the mid-latitude region (north of the Tropic of Cancer), not in the tropical region, therefore they are called as mid-latitude storms or extra-tropical storms.
  • The low pressure typically forms over the Mediterranean Sea and travels over Iran, Iraq, Afghanistan, and Pakistan before entering India loaded with moisture.
  • Before its arrival, the weather turns unusually hot with a cloudy sky.
  • The rain brought by the system is beneficial for the rabi crops and helps in increasing food crop production, especially wheat.

Indian Monsoon

Context:

  • No, El Nino expected, it will be a ‘normal’ monsoon.

About:

  • The southwest monsoon is likely to be “normal” in 2022,.
  • Normal is 98% of the historical average of 88 cm of rainfall for the four months from June to September
  • The El Nino is not expected to surface this year. Its converse, or La Nina, had helped with two years of above-normal rainfall in 2019 and 2020 and “normal” rainfall in 2021

ENSO:

  • The Southern Oscillation is a change in air pressure over the tropical Pacific Ocean.
  • When coastal waters become warmer in the eastern tropical Pacific (El Niño), the atmospheric pressure above the ocean decreases.
  • Climatologists define these linked phenomena as El Niño-Southern Oscillation (ENSO). 

El Nino:

  • El Niño is a climate pattern that describes the unusual warming of surface waters in the eastern tropical Pacific Ocean. El Nino is the “warm phase” of a larger phenomenon called the El Nino-Southern Oscillation (ENSO).
  • El Niño events occur irregularly at two- to seven-year intervals. However, El Niño is not a regular cycle, or predictable in the sense that ocean tides are.
  • El Niño, meaning “the little boy” in Spanish.
  • It leads to less rainfall in India and can even precipitate drought-like conditions.

La Nina:

  • La Niña is a weather pattern that occurs in the Pacific Ocean.
  • In this pattern, strong winds blow warm water at the ocean’s surface from South America to Indonesia.
  • As the warm water moves west, cold water from the deep rises to the surface near the coast of South America.
  • This leads to normal or more than average rainfall in India.

Long Period Average

Context:

  • IMD revised the long period average for the Indian monsoon to 87 cm.

About Long Period Average (LPA):

  • Long Period Average (LPA) is the average rainfall received over a 50-year period between 1971 and 2021. This average comes to 87cm of rainfall.
  • A 50-year LPA covers for large variations in either direction caused by freak years of unusually high or low rainfall (as a result of events such as El Nino or La Nina), as well as for the periodic drought years and the increasingly common extreme weather events caused by climate change.

Revisions in LPA:

  • The Long-period average is revised every decade and it has been continually decreasing for India. It was 89 cm for the period ranging from 1951- to 2000.
  • Then it got reduced to 88 m for years 1961-2010 and the latest revision for the period 1971-2020 is 87cm.

Dry and Wet Epochs:

  • The decrease in the seasonal rainfall is due to the natural multidecadal epochal variability of wet and dry epochs of India’s rainfall.
  • Over a century, the average rainfall changes every decade with roughly 30 years of a declining trend followed by 30 years of an upswing.
  • Currently, India is at the end of a dry epoch and it seems to be entering a wet epoch.

Facts to remember:

  • The Southwest monsoon accounts for about 75 per cent of the country’s annual rainfall.
  • About 75 per cent of this occurs during June to September monsoon season.
  • July and August remain the wettest months of the year, accounting for 70 per cent of the season’s total rainfall.
  • About 78 per cent of the country’s gross cropped area is supported by monsoon rainfall.

Indian Ocean Dipole (IOD)

About:

  • It is an atmosphere-ocean coupled phenomenon in the Indian Ocean, characterized by a difference in sea-surface temperatures.
  • IOD is the difference between the temperature of the eastern (Bay of Bengal) and the western Indian Ocean (Arabian Sea).
  • IOD develops in the equatorial region of the Indian Ocean from April to May, peaking in October.

Phases of IOD:

  • Neutral Phase of IOD: The neutral IOD refers to both western basin and eastern basin showing almost equal temperatures.
  • Positive Phase of IOD: The positive IOD refers to the warmer western basin of the Indian Ocean as compared to the Eastern basin.
  • Negative Phase of IOD: The negative IOD refers to the cooler western basin of the Indian Ocean as compared to the Eastern basin.

COLD WAVE IN NORTH DELHI

Context:

  • The winter of 2021-22 in India, particularly in North India, has been extremely cold and unusually long. The days have felt chillier and colder than normal.
  • The days are wetter when compared to previous years too.

What are the Causes?

  • Western Disturbances: Until January 25th, 2022, seven western disturbances passed over India, practically all of which were severe enough to generate widespread rain, snowfall, and unstable weather in the regions.
  • La Nina: La Nina is connected with the more frequent and highest numbers of western disturbances. At the moment, moderate-intensity La Nina conditions exist, which manifest as cooler-than-normal sea surface temperatures in the equatorial Pacific Ocean.
  • Cold Winds from the Far North: After a western disturbance sweeps India, cold winds from the country's far north penetrate to lower latitudes resulting in cold weather.
  • Moisture and low-lying clouds: The availability of moisture and the presence of low-lying clouds along the Indo-Gangetic plains favored cold day conditions.

El-Nino and la-Nina:

Western Disturbance:

  • Western Disturbances develop in the mid-latitude region (north of the Tropic of Cancer), not in the tropical region; therefore they are called mid-latitude storms or extra-tropical storms.
  • Western Disturbances are low-pressure systems, embedded in western winds (westerlies) that flow from the west to the east.
  • This western disturbance is also the reason for the precipitation of snow and rain over Northwest India and sometimes, other parts of North India.

SOUTHWEST MONSOON DELAY

Context:

  • The southwest monsoon, one of the most stable weather systems on the planet, has gone for a toss in 2021. As of July 12, the country-wide deficit in monsoon rainfall stood at seven percent below normal.

About:

  • Reasons for Delay
    • The monsoon was delayed due to lower-than-usual temperatures in northern Pakistan and northern India. Hence, led to the absence of the formation of the low-pressure system over the north Bay of Bengal.
    • The Madden Julian Oscillation is an eastward-moving pulse of cloud and rainfall.

Madden Julian Oscillation(MJO)

  • The MJO can be defined as a disturbance of clouds, wind, and pressure, moving eastward at a speed of 4-8 meters per second, the MJO goes around the globe in 30-60 days on average. Sometimes, it can take 90 days.
  • It’s an eastward traversing phenomenon and is most prominent over the Indian and Pacific Oceans.
  • The journey of MJO goes through eight phases. When it is over the Indian Ocean during the Monsoon season, it brings good rainfall over the Indian subcontinent. On the other hand, when it witnesses a longer cycle and stays over the Pacific Ocean, MJO brings bad news for the Indian Monsoon.

ATLANTIC MERIDIONAL OVERTURNING CIRCULATION (AMOC)

Context:

  • A recent study in Nature Climate Change and the IPCC’s Report (AR6) notes that the Atlantic Meridional  Overturning Circulation (AMOC) is losing its stability.
  • Modeling studies have shown that an AMOC shutdown would cool the northern hemisphere and decrease rainfall over Europe.

About:

  • The AMOC is a large system of ocean currents.
  • It is the Atlantic branch of the ocean conveyor belt or Thermohaline circulation (THC) and distributes heat and nutrients throughout the world’s ocean basins.
  • AMOC carries warm surface waters from the tropics towards the Northern Hemisphere, where it cools and sinks.
  • It then returns to the tropics and then to the South Atlantic as a bottom current. From there it is distributed to all ocean basins via the Antarctic circumpolar current.

What happens if AMOC collapses?

  • Gulf Stream, a part of the AMOC, is a warm current responsible for mild climates on the Eastern coast of North America as well as Europe. Without a proper AMOC and Gulf Stream, Europe will be very cold.
  • It can also affect El Nino.
  • Freshwater from melting Greenland ice sheets and the Arctic region can make circulation weaker as it is not as dense as salt water and doesn’t sink to the bottom.

Why is the AMOC slowing down?

  • Global warming can cause a weakening of the major ocean systems of the world.
  • A part of the Arctic’s ice called the “Last Ice Area” has also melted. The freshwater from the melting ice reduces the salinity and density of the water. Now, the water is unable to sink as it used to and weakens the AMOC flow.
  • As the Indian Ocean warms faster and faster, it generates additional precipitation. With so much precipitation in the Indian Ocean, there will be less precipitation in the Atlantic Ocean, leading to higher.

Influence of the Indian Ocean:

  • Another study suggested that the Indian Ocean may also be helping the slowing down of AMOC.
  • As the Indian Ocean warms faster and faster, it generates additional precipitation.
  • With so much precipitation in the Indian Ocean, there will be less precipitation in the Atlantic Ocean, leading to higher salinity in the waters of the tropical portion of the Atlantic.
  • This saltier water in the Atlantic, as it comes north via AMOC, will get cold much quicker than usual and sink faster.
  • This acts as a jump start for AMOC, intensifying the circulation.

HEAT DOME

Context:

  • Recently, the Pacific Northwest and some parts of Canada recorded temperatures around 47 degrees, causing a “historic” heatwave.
  • This is a result of a phenomenon referred to as a “heat dome”.

About:

  • The phenomenon begins when there is a strong chance (or gradient) in ocean temperatures. In the process known as convection, the gradient causes more warm air, heated by the ocean surface, to rise over the ocean surface.
  • As prevailing winds move the hot air east, the northern shifts of the jet stream trap the air and move it toward land, where it sinks, resulting in heatwaves.
  • Jet streams are relatively narrow bands of strong wind in the upper levels of the atmosphere. The winds blow from west to east in jet streams but the flow often shifts to the north and south.
  • This strong change in ocean temperature from the west to the east is the reason for the heat dome (HD).
  • The western Pacific ocean’s temperatures have increased in the past few decades and are relatively more than the temperature in the eastern Pacific.
  • HD also prevents clouds from forming, allowing for more radiation from the sun to hit the ground.
  • A heat dome is effectively what it sounds like – an area of high pressure that parks over a region like a lid on a pot, trapping heat. They are more likely to form during La Niña years like 2021 when waters are cool in the eastern Pacific and warm in the western Pacific.

Heat Wave:

  • A heatwave is a period of abnormally high temperatures, more than the normal maximum temperature that lasts for more than two days.
  • Heatwaves typically occur between March and June, and in some rare cases even extend till July.
  • Heatwaves can occur with or without high humidity and have the potential to cover a large area, “exposing a high number of people to hazardous heat.”
  • Impact on Humans (Wet-bulb temperature):
  • As long as the body is producing sweat, which is then able to evaporate quickly, the body will be able to remain cool even under high temperatures.
  • Wet-bulb temperature (WBT) is a limit that considers heat and humidity beyond which humans can not tolerate high temperatures.
  • Temperatures beyond WBT can cause heat-related illnesses including heatstroke, heat exhaustion, sunburn, and heat rashes. Sometimes these can prove fatal.

Effects of Heat Dome:

  • Those living without an air conditioner see the temperatures of their homes rising to unbearably high, leading to sudden fatalities.
  • The trapping of heat can also damage crops, dry out vegetation and result in droughts.
  • The sweltering heatwave will also lead to rising in energy demand, especially electricity, leading to pushing up rates.
  • The heat domes can also act as fuel to wildfires, which destroys a lot of land area in the US every year.

Climate change and heat domes:

  • Weather scientists have been highlighting the effects of climate change on more extreme heatwaves.
  • According to a 2017 NOAA (National Oceanic and Atmospheric Administration) survey, average US temperatures have increased since the late 19th century.
  • However, Scientists are usually wary of linking climate change to any contemporary event mainly because of the difficulty in completely ruling out the possibility of the event having been caused by some other reason, or being a result of natural variability.

       

SUMMER SOLSTICE

Context:

  • June 21- 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.

What causes this?

  • Solstice means “sun stands still” in Latin.
  • A solstice is an astronomical event, caused by Earth’s tilt on its axis and its motion in orbit around the sun.
  • At the June solstice, Earth is positioned in its orbit so that our world’s the North Pole is leaning most toward the sun.
  • As seen from Earth, the sun is directly overhead at noon 23 1/2 degrees north of the equator, at an imaginary line encircling the globe known as the Tropic of Cancer – named after the constellation Cancer, the Crab. This is as far north as the sun ever gets.

Implications:

  • All locations north of the equator have days longer than 12 hours at the June solstice. Meanwhile, all locations south of the equator have days shorter than 12 hours.
  • This day is characterized 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 percent higher at the North Pole than at the Equator.

What is the winter solstice?

  • 21st December or the Winter Solstice marks the shortest day of the year in the Northern Hemisphere.
  • It is the shortest day and longest night of the year in the Northern Hemisphere and is also known as the 'first day of winter’ in the Northern Hemisphere as well as ‘Hiemal solstice or Hibernal solstice’.
  • During this, countries in the Northern Hemisphere are farthest from the Sun and the Sun shines overhead on the Tropic of Capricorn (23.5° south).

HIGH TIDE WARNING FOR COASTAL AREAS

Context:

  • The West Bengal government issued an alert in the coastal areas and evacuated a few thousand people from islands exposed to the Bay of Bengal over fears of fresh inundation due to a high tide on Friday.

Tides: 

  • The Periodic rise and fall of the sea level due to the gravitational pull of the Moon and Sun, once or twice a day, are called tides.
  • Ocean Tides are one type of wave characterized by rhythmic rise and fall of ocean water twice a day.
  • Tides make ocean water move vertically.

Cause of tides

  • The gravitational pull of the Moon.
  • Gravitation pull of Sun. 
  • Centrifugal force is the force that works as a counterbalance of gravity.
  • Gravitation pull and centrifugal force are responsible for the creation of two major tides on earth.
  • On the moonward side of the earth, a tidal bulge is caused by the gravitational pull from the Moon, and the opposite side of the earth's bulge is caused by centrifugal force.

Types of tides:

  • Based on the frequency of tide, the following are the types of tides:
    • Semi-diurnal tide: Two high and two low tides with the same height on each day.
    • Diurnal tides: Only one high tide and one low tide with the same height each day.
    • Mixed Tides: Tides having variation in height is called mixed tide.
  • Types of tides based on the Sun, Moon, and earth Position:
    • Spring Tides: During full moon and new moon days. The sun, moon, and earth are the same line and tides are highest.
    • Neap Tides: When the moon is the first and last quarter, ocean water gets diagonally opposite direction resulting in low tides. These are called neap tides.

The factors affecting the height of the tides:

  • When the Moon is close to earth at Perigee position; experiences higher tides or greater than the normal tides.
  • When the Moon is the farthest from the earth at apogee position; experiences less than average tides bulge.
  • When the Earth is closed to Sun at Perihelian position; experiences higher tides or greater than the normal tides.
  • When the Earth is the farthest from the Sun at the aphelian position; experiences less than average tides bulge.
  • Ebb: It is the time between the high tide and low tides when water is falling.
  • Flood or flow: It is the time between the low tide and high tides when water is rising.

Tide pools

  • Tides form tide pools. These small pools of water are often left behind among the rocks at low tide.
  • They can include a diverse population of tiny plants and animals that may serve as food for larger species.

Tide flooding

  • As the sea level rises, it can be easy to miss the subtlety of higher water. It’s much harder to overlook saltwater more frequently flooding streets, impeding daily life and making existing problems worse.
  • The frequency of high-tide flooding along the coasts results in tide flooding Perigean Spring Tide
  • During a perigean spring tide, those areas that normally experience frequent high tide flooding may see even higher levels of inundation with a longer duration.

RAINY OCTOBER

Context:

  • The South-west monsoon withdrawal is late in several places and also states like Kerala, Delhi, Madhya Pradesh, and Uttarakhand, for example, have received very high rainfall in October.

About:

  • Scientists say a combination of factors — delayed monsoons and development of low-pressure areas at multiple places — have resulted in these rainfall events at several places.
  • Western disturbances, which begin to have significant interference in local weather over the extreme northern parts of India, commonly cause either rain or snowfall.
  • In the middle of October, two low-pressure systems were active simultaneously, one each over the Arabian Sea and the Bay of Bengal regions.

South-west Monsoons:

  • Out of a total of 4 seasonal divisions of India, monsoon occupies 2 divisions, namely:
    • The southwest monsoon season – Rainfall received from the southwest monsoons is seasonal, which occurs between June and September.
    • The retreating monsoon season – The months of October and November are known for retreating monsoons.
  • Factors influencing Southwest monsoon:
    • The differential heating and cooling of land and water create a low pressure on the landmass of India while the seas around it experience a comparatively high pressure.
    • The shift of the position of Inter-Tropical Convergence Zone (ITCZ) in summer, over the Ganga plain
    • Mascarene high, the presence of the high-pressure area, east of Madagascar.
    • The Tibetan plateau gets intensely heated during summer, which results in strong vertical air currents and the formation of low pressure over the plateau.
    • The movement of the westerly jet stream to the north of the Himalayas and the presence of the tropical easterly jet stream over the Indian peninsula during summer.
    • La Nina and El-Nino, which increase or decrease the monsoon intensity, respectively.

Natural Disasters

VOLCANOS

Context:

  • Mount Semeru, the eruption of the biggest mountain on the island of Java in Indonesia. Similarly, let's see the important volcanoes in the year 2021-22.
Volcano/mountain name Type Place/Location
Mount Semeru aka Mahameru Stratovolcano East Java, Indonesia.
La Soufriere volcano Stratovolcano Caribbean’s Saint Vincent
 Kilauea volcano Shield Volcano Hawaii
MOUNT SINABUNG Stratovolcano  Indonesia

Types of Volcanoes:

Volcano Features
Fissure Volcano
  • A fissure Volcano is a linear volcanic vent through which lava erupts, usually without any explosive activity.
  • Fissure vents can cause large flood basalts which run first in lava channels and later in lava tubes.

Shield Volcano

  • The Shield volcanoes are the largest of all the volcanoes on earth, which are not steep.
  • These volcanoes are mostly made up of basalt.
  • They become explosive only if in some way water gets into the vent, otherwise, they are characterized by low explosivity.
  • Ex: Hawaiian shield volcanoes
Composite Volcano
  • These volcanoes are also called Stratovolcanoes
  • Composite volcanoes are characterized by outbreaks of cooler and more viscous lavas than basalt.
  • Large quantities of pyroclastic material and ashes find their way to the ground along with lava.
  • Ex: Mayon Volcano in the Philippines, Mount Fuji in Japan, and Mount Rainier in Washington
Caldera
  • Calderas are known as the most explosive volcanoes on Earth.
  • When they erupt, they are inclined to collapse on themselves rather than construct any structure.
  • The collapsed depressions are known as calderas.
  • Ex: Crater Lake, in Oregon.
Mid-Ocean Ridge Volcanoes
  • These volcanoes are found in oceanic areas.
  • There exists a system of mid-ocean ridges stretching for over 70000 km all through the ocean basins.
  • The central region of this ridge gets frequent eruptions.

 

CYCLONE

Context:

  • The year 2021-22 saw many cyclones already like Jawad, Yaas in May and Gulab in September, etc.

Basics:

  • Tropical cyclones are formed only over warm ocean waters near the equator.
  • When warm, moist air over the ocean rises upward from near the surface, a cyclone is formed.
  • When the air rises up and away from the ocean surface, it creates an area of lower air pressure below.
  • It causes the air from surrounding areas with higher pressure to move towards the low-pressure area, which further leads to warming up of the air and causes it to rise above.
  • As the warm, moist air rises and cools, the water in the air forms clouds.
  • The complete system of clouds and wind spins and grows, along with the ocean's heat and water evaporating from the ocean surface.
  • As the wind system rotates with increasing speed, an eye gets formed in the middle. The center of a cyclone is very calm and clear with very low air pressure.
  • The difference in temperature between warm, rising, and cooler environments cause the air to rise and become buoyant.
  • Annually, around 70 to 90 cyclonic systems develop all over the globe. The Coriolis force causes the wind to spiral around a low-pressure area.
  • As the presence of Coriolis forces is negligible in the equatorial belt between 5 degrees north and 5 degrees south latitudes, hence cyclonic systems do not develop in this region.

HURRICANE IDA

Context:

  • Recently, Hurricane Ida made landfall in Louisiana, US. It is an extremely dangerous Category 4 storm and one of the most powerful storms ever to hit the US.

Names in Different Regions of the World:

  • Typhoons: Tropical cyclones are known as Typhoons in the China Sea and the Pacific Ocean.
  • Hurricanes: In the West Indian islands in the Caribbean Sea and the Atlantic Ocean.
  • Willy-willies: In north-western Australia
  • Tropical Cyclones: In the Indian Ocean Region.

Categorization of Hurricanes:

  • Hurricanes are categorized on the Saffir-Simpson Hurricane Wind Scale, which rates them on a scale of 1 to 5 based on wind speed.
  • Hurricanes that reach category three or higher are classified as major hurricanes.

GLACIAL LAKE ATLAS OF GANGA RIVER BASIN

Context:

  • With concerns mounting over the impact of climate change on Himalayan glaciers, the Ministry of Jal Shakti has released an updated atlas of glacial lakes that are part of the Ganga river basin.

About:

  • The present glacial lake atlas is based on the inventoried glacial lakes in part of the Ganga River basin from its origin to the foothills of the Himalayas covering a catchment area of 2,47,109 sq. km.
  • The study portion of the Ganga River basin covers part of India and the transboundary region.
  • The Atlas is available on the Bhuvan portal of NRSC, ISRO (https://bhuvan.nrsc.gov.in/nhp/ ), India WRIS Portal (www.indiawris.gov.in ) and NHP web site of DoWR, RD & GR (www.nhp.mowr.gov.in).
  • This is an initiative under NHP, a Central Sector Scheme implemented by the Department of Water Resources, River Development & Ganga Rejuvenation (DOWR, RD & GR).

What are Glacial lakes?

  • A glacial lake is a body of water with origins from glacier activity.
  • They are formed when a glacier erodes the land, and then melts, filling the depression created by the glacier.

How are glaciers and glacial lakes formed?

  • Glaciers are found on every continent except Australia and some are hundreds of thousands of years old, and a large cluster of glaciers are in the Himalayas.
  • Glaciers are made of layers of compressed snow that move or “flow” due to gravity and the softness of ice relative to rock.
  • A glacier’s “tongue” can extend hundreds of kilometers from its high-altitude origins, and the end, or “snout,” can advance or retreat based on snow accumulating or melting.
  • Proglacial lakes, formed after glaciers retreat, are often bound by sediment and boulder formations.
  • Additional water or pressure, or structural weakness, can cause both natural and manmade dams to burst, sending a mass of floodwater surging down the rivers and streams fed by the glacier.

What is GLOF?

  • A GLOF is a type of outburst flood that occurs when the dam containing a glacial lake fails.
  • An event similar to a GLOF, where a body of water contained by a glacier melts or overflows the glacier, is called a jökulhlaup.
  • The dam can consist of glacier ice or a terminal moraine.

EARTHQUAKE IN NORTH-EAST REGION

Context:

  • A major earthquake measuring 6.4 on the Richter Scale jolted Northeast India, originated in Tezpur of Assam, and tremors were felt across Assam, North Bengal.

About:

  • According to the National Centre of Seismology, the earthquake measuring 6.4 on the Richter Scale originated in Sonitpur, Tezpur of Assam.
  • There were six aftershocks following the first major earthquake.

Earthquake:

  • An earthquake in simple words is the shaking of the earth. It is a natural event. It is caused due to release of energy, which generates waves that travel in all directions.
  • The vibrations called seismic waves are generated from earthquakes that travel through the Earth and are recorded on instruments called seismographs.
  • The location below the earth’s surface where the earthquake starts is called the hypocenter, and the location directly above it on the surface of the earth is called the epicenter.

Types of Earthquake:

  • Fault Zones Earthquake: 
    • Release of energy occurs along a fault. A fault is a sharp break in the crustal rocks.
    • Rocks along a fault tend to move in opposite directions. As the overlying rock strata press them, the friction locks them together.
  • Human-Induced Earthquakes:
    • In the areas of intense mining activity, sometimes the roofs of underground mines collapse causing minor tremors. These are called collapse earthquakes.
    • Ground shaking may also occur due to the explosion of chemical or nuclear devices. Such tremors are called explosion earthquakes.
    • Reservoir-induced earthquakes in the areas of large reservoirs.
  • Volcanic Earthquake:
    • Earthquakes produced by stress changes in solid rock due to the injection or withdrawal of magma (molten rock) are called volcano earthquakes.
    • These earthquakes can cause the land to subside and can produce large ground cracks. These earthquakes can occur as the rock is moving to fill in spaces where magma is no longer present.
  • Tectonic Earthquakes:
    • When tectonic plates move, it also causes movements at the faults. Thus, the slipping of land along the faultline along convergent, divergent, and transform boundaries causes earthquakes.
    • The point where the energy is released is called the focus of an earthquake, alternatively, it is called the hypocentre. The energy waves traveling in different directions reach the surface.

Measurement of Earthquakes

  • Mercalli Scale:
    •  
    • The scale represents the intensity of the earthquake by analyzing the after-effects like how many people felt it, how much destruction occurred etc.
    • The range of intensity is from 1-to 12.
  • Richter Scale:
    •  
    • The scale represents the magnitude of the earthquake. The magnitude is expressed in absolute numbers from 1-10.
    •  
    • Each whole-number increase in the Richter scale represents a ten times increase in the power of an earthquake.

Earthquake zones in India

Types of Earthquake waves: Earthquake waves are basically of two types — body waves and surface waves.

  • Body waves are generated due to the release of energy at the focus and move in all directions traveling through the body of the earth. Hence, the name body waves.
    • P-waves move faster and are the first to arrive at the surface. These are also called primary waves. The P-waves are similar to sound waves. They travel through gaseous, liquid, and solid materials.
    • S-waves arrive at the surface with some time lag. These are called secondary waves. An important fact about S-waves is that they can travel only through solid materials.
  • The body waves interact with the surface rocks and generate a new set of waves called surface waves. These waves move along the surface.
    • Love waves: This kind of surface wave causes horizontal shifting of the earth during an earthquake.
    • Rayleigh waves: These waves follow an elliptical motion. A Rayleigh wave rolls along the ground just like a wave rolls across a lake or an ocean.

Cyclone Asani 

Context:

  • Year’s 1st cyclone Asani likely to form over Bay of Bengal on Mar 21.

About:

  • A low-pressure area that formed over the southwest Indian Ocean is expected to intensify into a cyclone this week.
  • The Cyclone has been named The name was suggested by India’s southern neighbour Sri Lanka.
  • It is expected to travel along and off the coast of the Andaman and Nicobar Islands before it intensifies into a depression.

LANDSLIDES IN HIMACHAL

Context:

  • Rescue operations are underway in the Boh valley in Kangra district after a landslip, in which one person died and nine are feared trapped beneath the debris.

Landslides:

  • A landslide is defined as the movement of a mass of rock, debris, or earth down a slope.
  • They are a type of mass wasting, which denotes any downward movement of soil and rock under the direct influence of gravity.
  • The term landslide encompasses five modes of slope movement: falls, topples, slides, spreads, and flows.

Landslides Causes:

  • Slope movement occurs when forces acting downward (mainly due to gravity) exceed the strength of the earth materials that compose the slope.
  • Landslides are caused due to three major factors: geology, morphology, and human activity.
  • Geology refers to the characteristics of the material. The earth or rock might be weak or fractured, or different layers may have different strengths and stiffness.
  • Morphology refers to the structure of the land. For example, slopes that lose their vegetation to fire or drought are more vulnerable to landslides.
  • Vegetation holds soil in place, and without the root systems of trees, bushes, and other plants, the land is more likely to slide away.
  • Human activity which includes agriculture and construction increases the risk of a landslide.

Mitigation:

  • Restriction on the construction and other developmental activities such as roads and dams in the areas prone to landslides.
  • Limiting agriculture to valleys and areas with moderate slopes.
  • Control on the development of large settlements in the high vulnerability zones.
  • Promoting large-scale afforestation programs and construction of bunds to reduce the flow of water.
  • Terrace farming should be encouraged in the northeastern hill states where Jhumming (Slash and Burn/Shifting Cultivation) is still prevalent.

Economic Geography

RIVER CITIES ALLIANCE

Context: 

  • Recently, River Cities Alliance has been launched by M.Jal Shakti and M.Housing.

About:

  • It is a dedicated platform for river cities in India to ideate, discuss and exchange information for the sustainable management of urban rivers. That will focus on three broad themes: Networking, Capacity Building, and Technical Support.
  • The focus will be on minimizing the water footprint of cities
  • The Alliance cities will work towards adopting and localizing national policies and instruments with key river-related directions; prepare their Urban River Management Plans, and develop city-specific sectoral strategies that are required for sustainable urban river management.
  • SDG 6 talks about clean water and sanitation.

THE KEN-BETWA RIVER INTERLINKING (KBRIL) PROJECT

Context: 

  • The Ken-Betwa River Interlinking (KBRIL) Project will lead to the submergence of a major portion of the core area of the Panna Tiger Reserve in Madhya Pradesh, triggering a major loss of the tiger and its major prey species such as chital and sambar.

About:

  • KBRIL is a river-interlinking project that aims to transfer surplus water from the Ken river in Madhya Pradesh to Betwa in Uttar Pradesh to irrigate the drought-prone Bundelkhand region. Both Ken and Betwa are the tributaries of the Yamuna.
  • The National Interlinking of Rivers Authority (NIRA) has the power to set up SPV for individual link projects.
  • A Special Purpose Vehicle (SPV) called Ken-Betwa Link Project Authority (KBLPA) will be set up to implement the project.

Panna Tiger Reserve:

  • Panna Tiger Reserve is one of the important and successful tiger recovery reserves in the country.
  • A species recovery plan was developed to reinforce the tiger population, because of which the tiger population has increased from 0 in 2009 to 54 in 2019.
  • Panna Tiger Reserve has included in the global network of biosphere reserves by the United Nations Educational, Scientific, and Cultural Organization (UNESCO) in 2020.
  • UNESCO cited the PTR as a critical tiger habitat.

Yamuna River 

  • It originates from the Yamunotri Glacier on the southwestern slopes or Banderpoonch peak in the Mussoorie range of the lower Himalayas.
  • The cities of Bhagpat, Delhi, Noida, Mathura, Agra, Firozabad, Etawah, Hamirpur, and Allahabad lie on its banks.
  • The largest tributary of the Ganga in the northern plains. Flows along states of Uttarakhand, Himachal Pradesh, Haryana enters Delhi and merges with the Ganga near Triveni Sangam, Allahabad(Prayagraj).
  • The important tributaries of the Yamuna River are Tons, Chambal, Hindon, Betwa, and Ken. Other tributaries include the Giri, Sind, Uttangan, Sengar, and the Rind.

 

SOLAR HAMAM

The Solar Hamam is essentially a heating system developed to generate heat in a clean, environmentally-friendly way for households across mountainous regions. The Solar Hamam has won the “Himachal Pradesh State Innovation Award for 2016-17.

How Does This System Work

  • Within the first solar illumination of the day in the morning of around 30-35 minutes, it can heat anywhere between 15-18 liters of hot water.
  • It uses a solar panel to facilitate this heating process.
  • The Solar Hamam consists of a unique anti-freezing outlet. 

EARTH'S BLACK BOX

Context: 

  • Scientists in Australia are building a ‘black box’ that will chronicle the ravages of climate change.

About:

  • In a remote part of Australia, a steel vault about the size of a school bus will record the Earth’s warming weather patterns.
  • It will listen to what we say and do. In a way held us accountable for our actions against climate change
  • It will create an archive that could be critical to piecing together the missteps, its creators say, should humanity be destroyed by climate change.
  • It will operate much like a plane’s flight recorder, which records an aircraft’s final moments before crashing.
  • It will collect climate-change-related data like land and sea temperature measurements, species extinction, energy consumption, human population, ocean acidification, and atmospheric CO2 levels.

ONE SUN ONE WORLD ONE GRID INITIATIVE

Context:

  • India and the UK are likely to launch the ‘green grids’ initiative—the One Sun One World One Grid (OSOWOG) project—on the sidelines of the COP26 summit.

About:

  • OSOWOG is India’s initiative to build a global ecosystem of interconnected renewable energy resources.
  • The blueprint for the OSOWOG will be developed under the World Bank’s technical assistance program.
  • OSOWOG will be implemented to accelerate the deployment of grid-connected rooftop solar installations.

Benefits of the Programme:

  • The global project aims to power the world with clean energy.
  • Tackle access to energy for underserved people and communities. For example, it will help people access clean drinking water, access clean cooking fuel, and bring lighting to millions of homes.
  • Exponential leap towards clean energy transition.
  • It envisions the transfer of surplus renewable electricity at a near-zero cost. Thus, enabling access to affordable solar energy.
  • It will help countries like Singapore and Bangladesh, which have a very high population density, to have access to renewable energy.
  • Address the issue of the intermittency of solar power. OSOWOG will employ battery storage to make round-the-clock solar energy dispatches at greatly cheaper rates.

Solar energy:

  • There are two ways we can produce electricity, from sunlight:
    • Photovoltaic Electricity: Solar photovoltaic (SPV) cells convert solar radiation (sunlight) into electricity. A solar cell is a semiconductor device made of silicon and/or other materials, which, when exposed to sunlight, generates electricity.
    • Solar-Thermal Electricity – Solar thermal energy uses a solar collector that has a mirrored surface that reflects the sunlight onto a receiver that heats a liquid. This heated up liquid is used to make steam that produces electricity.
  • The scenario in India:
    • India lying in the tropical belt has the advantage of receiving peak solar radiation for 300 days, amounting to 2300-3,000 hours of sunshine equivalent to above 5,000 trillion kWh.
    • Solar power in India is a fast developing industry as part of the renewable energy in India. The country’s solar installed capacity was 44.3 GW as of 31 August 2021.
    • India’s Intended Nationally Determined Contributions (INDC’s) commitment includes 100 GW of solar power out of 175 GW of renewable energy by 2022.

PALK BAY SCHEME

Context:

  • The Union Government is considering increasing the unit cost of deep-sea fishing vessels under the Palk Bay scheme to make it more attractive to fisherfolk.
  • The original unit cost of Rs 80 lakh was “inadequate” [to meet the requirements of the fisherfolk].

About the Palk Bay scheme:

  • It was launched by the Prime Minister in July 2017, as part of the umbrella Blue Revolution Scheme.
  • It is being financed by the Union and the State Governments with beneficiary participation.
  • It envisages the provision of 2,000 vessels in three years to the fishermen of the
  • State to motivate them to abandon bottom trawling.

What is bottom trawling?

  • Bottom trawling is a fishing practice that herds and captures the target species, like groundfish or crabs, by towing a net along the ocean floor.
  • Bottom trawling, an ecologically destructive practice, involves trawlers dragging weighted nets along the seafloor, causing great depletion of aquatic resources.

Darlong community

Context:

  • The Lok Sabha on Monday passed a bill to include the Darlong community as a subtribe of the Kuki tribe on the list of Scheduled Tribes of Tripura.

Darlong community:

  • The Darlong are a small tribe and represent a minority community in Tripura.
  • Traditionally, the Darlongs adopt Jhum cultivation/shifting cultivators.
  • Today, most of them have taken up agroforestry and horticultural plantation or orchard development as their main livelihoods in addition to wet rice cultivation and seasonal vegetable cultivation.
  • The Darlongs have customary laws and practices to govern them and dispense their own affairs

Aluminium

Context:

  • The Indian Railways (IR) plans to use Aluminium to produce body coaches in the new generation energy efficient Vande Bharat Train sets.

About:

  • Aluminium (Al) is a highly electropositive metal with an atomic number of 13.
  • Among metals, aluminium is the most abundant. It is the third most abundant element in earth’s crust (8.3% approx. by weight).
  • It is a major component of many igneous minerals like mica and clays.

Properties:

  • Even though Aluminium is a metal, it shows many chemical similarities to boron, a non-metal.
  • It has high tensile strength, high electrical and thermal conductivity.

Extraction:

  • For the purpose of extraction, Bauxite (Al2O3. 2H2O) and Cryolite (Na3AlF6) are chosen for aluminium.
  • From bauxite ore, aluminium is extracted using leaching.
  • In India, bauxite mining sites are located in Orissa (the largest bauxite producer), Jharkhand, Maharashtra, Chhattisgarh, Madhya Pradesh, etc.
  • Aluminium industry is the 2nd most important industry after the iron and steel industry.

Anodising:

  • Anodising is a process of forming a thick oxide layer of aluminium. Aluminium develops a thin oxide layer when exposed to air.
  • This aluminium oxide coat makes it resistant to further corrosion.
  • Resistance can be improved further by making the oxide layer thicker.
  • During anodising, a clean aluminium article is made the anode and is electrolysed with dilute sulphuric acid. The oxygen gas evolved at the anode reacts with aluminium to make a thicker protective oxide layer.

Deep Ocean Mission

Context:

  • Recently, the Ministry of Earth Sciences has launched the Deep Ocean Mission (DOM).

About:

  • Deep Ocean Mission aims to explore the deep ocean for resources. Also, for sustainable use of ocean resources, it aims to develop deep-sea technologies.

Nodal Ministry:

  • The Ministry of Earth Sciences(MoES) will be the nodal Ministry for implementing this mission.

Components of DOM:

  • Development of Manned Submersible Vehicle: 
  • A manned submersible will be developed to carry three people to a depth of 6,000 metres in the ocean with a suite of scientific sensors and tools.
  • NIOT & ISRO is jointly developing a Manned Submersible Vehicle.
  • National Institute of Ocean Technology (NIOT), an autonomous institute under the Ministry of Earth Sciences.

Development of Technologies for Deep Sea Mining: 

  • An Integrated Mining System will be also developed for mining polymetallic nodules at those depths in the central Indian Ocean.
  • Polymetallic nodules are rocks scattered on the seabed containing iron, manganese, nickel and cobalt.
  • The exploration studies of minerals will pave the way for commercial exploitation in the near future, as and when commercial exploitation code is evolved by the International Seabed Authority, a United Nations (UN) organisation.

Development of Ocean Climate Change Advisory Services:

  • It entails developing a suite of observations and models to understand and provide future projections of important climate variables on seasonal to decadal time scales.

Technological Innovations for Exploration and Conservation of Deep-sea Biodiversity:

  • Bio-prospecting of deep-sea flora and fauna including microbes and studies on sustainable utilisation of deep-sea bio-resources will be the main focus.

Deep Ocean Survey and Exploration:

  • It will explore and identify potential sites of multi-metal Hydrothermal Sulphides mineralization along the Indian Ocean mid-oceanic ridges.

Energy and Freshwater from the Ocean:

  • Studies and detailed engineering design for offshore Ocean Thermal Energy Conversion (OTEC) powered desalination plants are envisaged in this proof of concept proposal.
  • OTEC is a technology that uses ocean temperature differences from the surface to depths lower than 1,000 metres, to extract energy.

Advanced Marine Station for Ocean Biology:

  • It is aimed at the development of human capacity and enterprise in ocean biology and engineering.
  • It will translate research into industrial application and product development through on-site business incubator facilities.

ZOJILLA TUNNEL

Context:

  • Minister for Road Transport and Highways recently reviewed the construction work at the Zojila tunnel, which is likely to be ready by September 2026.

About the Zojila tunnel:

  • The tunnel will provide all-weather connectivity between Srinagar valley and Leh on NH-1 and will bring about an all-around economic and socio-cultural integration of Jammu and Kashmir.
  • It takes 3.5 hours to travel between Srinagar and Ladakh. The tunnel will reduce the travel time to 15 minutes.
  • The 14.15-km tunnel will be Asia’s longest bi-directional tunnel.

 

SUBANSIRI LOWER PROJECT

Context:

  • Work on the 2000 MW Subansiri Lower project resumed after being stopped in 2011 following protests amid fears of ecological damage and loss of livelihoods.

About:

  • It is located on the Subansiri River (largest tributary of Brahmaputra River), which is on the border of India’s two northeastern states, Arunachal Pradesh and Assam.
  • Subansiri River (gold river), originates in the Tibet Plateau and enters India through Miri hills in Arunachal Pradesh.
  • It is the largest tributary of the Brahmaputra River.
  • The project is being developed by the state-run National Hydro Power Corporation (NHPC).
  • It will be the single largest hydroelectric plant in India when completed. The project is expected to be completed in 2023.

National Hydro Power Corporation (NHPC):

  • NHPC is an enterprise of the Central Government incorporated with an objective to plan, promote and organize an integrated and efficient development of hydroelectric power in all aspects. Established: 1975
  • Besides, hydroelectric power, the company has expanded its objects to include other sources of energy like Solar, Geothermal, Tidal, Wind, etc.
  • At present, NHPC is a Mini Ratna Category-I Enterprise of the Central Government with an authorized share capital of Rs. 1,50,000 Million.

CHENNAI–KANYAKUMARI INDUSTRIAL CORRIDOR (CKIC)

Context:

  • The Asian Development Bank (ADB) and the Government of India have signed a $484 million loan to improve transport connectivity and facilitate industrial development in the Chennai–Kanyakumari Industrial Corridor (CKIC) in the state of Tamil Nadu.
  • CKIC is part of India’s East Coast Economic Corridor (ECEC), which stretches from West Bengal to Tamil Nadu.

What is an industrial corridor?

  • An industrial corridor is a corridor consisting of multi-modal transport services that would pass through the states as main arteries.
  • Industrial corridors offer effective integration between industry and infrastructure, leading to overall economic and social development.
  • Industrial corridors constitute world-class infrastructure, such as:
  • High-speed transportation network – rail and road.
  • Ports with state-of-the-art cargo handling equipment.
  • Modern airports.
  • Special economic regions/industrial areas.
  • Logistic parks/transshipment hubs.
  • Knowledge parks focused on catering to industrial needs.
  • Complementary infrastructure such as townships/real estate.

Significance of Industrial corridors:

  • Enhanced connectivity of industrial hubs with hinterland and ports will particularly help increase the
  • participation of Indian manufacturing in global production networks and global value chains, thereby creating jobs along the corridor.
  • The following eleven industrial corridor projects have been identified and approved for development by the Government of India:
    • Delhi Mumbai Industrial Corridor (DMIC)
    • Chennai Bengaluru Industrial Corridor (CBIC)
    • Extension of CBIC to Kochi via Coimbatore
    • Amritsar Kolkata Industrial Corridor (AKIC)
    • Hyderabad Nagpur Industrial Corridor (HNIC)
    • Hyderabad Warangal Industrial Corridor (HWIC)
    • Hyderabad Bengaluru Industrial Corridor (HBIC)
    • Bengaluru Mumbai Industrial Corridor (BMIC)
    • East Coast Economic Corridor (ECEC) with Vizag Chennai Industrial Corridor (VCIC) as Phase-1
    • Odisha Economic Corridor (OEC)
    • Delhi Nagpur Industrial Corridor (DNIC)
  • The development of these eleven industrial corridor projects will be implemented through the National Industrial Corridor Development and Implementation Trust (NICDIT). 

INDIA SET TO LAUNCH DEEP-SEA MISSION

Context:

  • The Union Cabinet has approved the long-pending Deep Ocean Mission.

About the Mission:

  • The mission proposes to explore the deep ocean similar to the space exploration started by ISRO about 35 years ago.
  • The focus of the mission will be on deep-sea mining, ocean climate change advisory services, underwater vehicles, and underwater robotics-related technologies.
  • The mission is expected to cost ₹4,077 crores over the next five years.
  • The Ministry of Earth Sciences (MoES) will be the nodal Ministry implementing this multi-institutional mission.

Key Components of the mission:

  • A manned submersible will be developed to carry three people to a depth of 6,000 meters in the ocean with a suite of scientific sensors and tools. An Integrated Mining System will be developed for mining polymetallic nodules at those depths in the central Indian Ocean.
  • Development of Ocean Climate Change Advisory Services.
  • Development of a component for searching deep-sea flora and fauna, including microbes, and studying ways to sustainably utilize them.
  • The next component is to explore and identify potential sources of hydrothermal minerals that are sources of precious metals formed from the earth’s crust along the Indian Ocean mid-oceanic ridges. 
  • It has a component for studying and preparing detailed engineering designs for offshore Ocean Thermal Energy Conversion (OTEC) powered desalination plants.
  • The final component is aimed at grooming experts in the fields of ocean biology and engineering. This component aims to translate research into industrial applications and product development through on-site business incubator facilities.

Significance:

  • The mission will give a boost to efforts to explore India’s vast Exclusive Economic Zone and Continental Shelf.
  • The plan will enable India to develop capabilities to exploit resources in the Central Indian Ocean Basin (CIOB).

Potential:

  • India has been allotted 75,000 square kilometers in the Central Indian Ocean Basin (CIOB) by the UN International Seabed Authority for the exploration of polymetallic nodules.
  • CIOB reserves contain deposits of metals like iron, manganese, nickel, and cobalt.
  • It is envisaged that 10% of the recovery of that large reserve can meet the energy requirements of India for the next 100 years.

What is the importance of PMN?

  • Polymetallic nodules (also known as manganese nodules) are potato-shaped, largely porous nodules found in abundance carpeting the seafloor of world oceans in the deep sea.
  • Composition: Besides manganese and iron, they contain nickel, copper, cobalt, lead, molybdenum, cadmium, vanadium, titanium, of which nickel, cobalt, and copper are considered to be of economic and strategic importance.

PALM OIL

Context: 

  • India to get technical help from Malaysia to increase palm oil plantations' footprint in India.

About:

  • India imports 60 percent of the edible oil it consumes and runs up an import bill of ₹80,000 crores. Of that, palm oil alone accounts for 55 percent.
  • While palm is the most prolific and efficient source of vegetable oil, it has a really bad reputation.
  • Activists call it the coal of the food world: bad for health, bad for the planet. 
  • In south-east Asia, palm monoculture has eaten into nearly 10 million hectares of forests. In middle-class perception, it’s an unhealthy oil. 
  • In the quest for self-sufficiency, the government last week introduced the National Mission for Edible Oil and Oil Palm (MNEO-OP), which seeks to give a big push to domestic palm oil cultivation.
  • In India, it is a farmers’ crop, grown in existing farmlands with intercropping.
  • Palm oil is rich in vitamin A and E, and in coenzymes like ubiquinone that help fight cardiac diseases.
  • Palm is good for sequestering carbon. It is actually a form of afforestation. A palm tree produces two to three new leaves per month. A lot of biomass, too, gets added to the soil.
  • The requirement of pesticides and herbicides is significantly less for oil palm compared to other crops.
  • If you look at the productivity levels of groundnuts, soybean, sunflower, sesame, and if you look at the oil palm productivity, it stands very tall. On average four to six tonnes of oil per hectare per year is produced through oil palm. For other oilseeds, it is about 0.4 tonnes.
  • The total water requirement is less than that for rice or sugarcane.
  • Palm oil is cheap because it is highly productive. Not because it's bad. The cost of cultivation is low and yields very high.

Tree City of The World

Context:

  • Mumbai has been recognised as ‘2021 Tree City of the World’ by the Food and Agriculture Organisation of the United Nations (UN) jointly with Arbor Day Foundation.
  • This is the first time Mumbai has made it to the list.
  • Hyderabad has been featured on this list for the second consecutive year.

Why Mumbai Gets The Recognition?

  • In 2018, residents of the city fought to save their mangrove forests from decomposing and their efforts saved more than 5,000 mangroves over the years.
  • Another example was to save the rich Aarey Forest. The 800-acre land area was under the Metro Car Shed project, but after protests, it was declared a reserve forest and the project was redesigned.
  • Sanjay Gandhi National Park acts as the lungs of Mumbai, providing fresh air.

About Tree City of the World tag:

  • The programme was started by the UN-FAO and Arbor Day Foundation, an American non-profit organisation.
  • The programme provides direction, assistance, and worldwide recognition for communities’ dedication to its urban forest, and provides a framework for a healthy, sustainable urban forestry programme in a city or a Town.

About Arbor Day Foundation:

  • It is a non-profit conservation and education organization established in 1972 in Nebraska, United States.
  • Its approach is to help others understand and use trees to address the challenges we face today, including air quality, water quality, changing climate, deforestation, poverty and hunger.

About Food and Agriculture Organization:

  • It is a specialized agency of the United Nations.
  • It was founded in October 1945 and the headquartered is in Rome, Italy.
  • It acts as a neutral policymaking forum and develops partnerships with all concerned with food & agriculture to ensure a world free from hunger.

Miscellaneous

EARTH’S FIRST LANDMASS EMERGED IN SINGHBHUM

Context:

  • A new study has challenged the widely accepted view that continents rose from the oceans about 2.5 billion years ago.

Significance:

  • Scientists have found sandstones in Singhbhum with geological signatures of ancient river channels, tidal plains, and beaches over 3.2 billion years old, representing the earliest crust exposed to air.

The Analysis:

  • The researchers studied granites that form the continental crust of the Singhbhum region.
  • These granites are 3.5 to 3.1 billion years old and formed through extensive volcanism that happened about 35-45 km deep inside the Earth and continued on and off for hundreds of millions of years until all the magma solidified to form a thick continental crust in the area.
  • Due to its thickness and less density, the continental crust emerged above the surrounding oceanic crust owing to buoyancy.
  • The researchers believe the earliest emergence of continents would have contributed to a proliferation of photosynthetic organisms, which would have increased oxygen levels in the atmosphere.

41ST SCIENTIFIC EXPEDITION TO ANTARCTICA

Context:

  • India has successfully launched the 41st Scientific Expedition to Antarctica with the arrival of the first batch of its contingent at the southern white continent.

About:

The 41st expedition has two major programs.

  • The first program encompasses geological exploration of the Amery ice shelf at Bharati station. This will help explore the link between India and Antarctica in the past.
  • The second program involves reconnaissance surveys and preparatory work for drilling of 500 meters of ice core near Maitri. It will help in improving the understanding of Antarctic climate, westerly winds, sea-ice, and greenhouse gases from a single climate archive for the past 10,000 years.

Indian Antarctic Program:

  • The Indian Antarctic Program comes under the control of the National Centre for Polar and Ocean Research, Ministry of Earth Sciences.
  • It was initiated in 1981 with the first Indian expedition to Antarctica.
  • The program gained global acceptance with India's signing of the Antarctic Treaty and subsequent construction of the Dakshin Gangotri Antarctic research base in 1983, superseded by the Maitri base from 1989.
  • The newest base commissioned in 2012, is Bharati.
  • Under the program, atmospheric, biological, earth, chemical, and medical sciences are studied by India.
  • As of today, Maitri and Bharati are fully operational.
  • The National Centre for Polar and Ocean Research (NCPOR), Goa—an autonomous institute under the Ministry of Earth Sciences—manages the entire Indian Antarctic program.

The Antarctic Treaty:

  • The Antarctic Treaty was signed in Washington on 1 December 1959 by the twelve nations (Argentina, Australia, Belgium, Chile, France, Japan, New Zealand, Norway, South Africa, United Kingdom, United States, and USSR).
  • The Treaty now has 52 signatories. India became a member of this treaty in 1983.
  • Headquarters: Buenos Aires, Argentina.
  • The Treaty applies to the area south of 60° South latitude.
  • It stipulates that Antarctica should be used exclusively for peaceful purposes. Military activities are specifically prohibited.
  • Guarantees continued freedom to conduct scientific research, promotes international scientific cooperation including the exchange of research plans and personnel.
  • Antarctica is not subject to the claims of any country.
  • Prohibits nuclear explosions and the disposal of radioactive waste.
  • Puts in place a dispute settlement procedure and a mechanism by which the Treaty can be modified.

Major International Agreements of the Treaty System:

  • The 1959 Antarctic Treaty.
  • The 1972 Convention for the Conservation of Antarctic Seals.
  • The 1980 Convention on the Conservation of Antarctic Marine Living Resources.
  • The 1991 Protocol on Environmental Protection to the Antarctic Treaty
  • The development of these agreements has allowed the implementation, with greater precision, of legally binding provisions for the regulation of activities in Antarctica.

CHINESE 'ARTIFICIAL SUN'

Context:

  • China's Experimental Advanced Superconducting Tokamak (EAST), also known as the 'Artificial Sun' experiment, has set a new record in the latest experiment, where it achieved a plasma temperature of 216 million Fahrenheit (120 million C) for 101 seconds.

Why is this significant?

  • It is believed that the temperature at the core of the Sun is 15 million C, which also means that the temperature produced by (EAST) is nearly seven times that of the Sun.
  • It is a significant step in the country’s quest to unlock clean and limitless energy, with minimal waste products.

What is EAST?

  • The mission mimics the energy generation process of the sun.
  • The reactor consists of an advanced nuclear fusion experimental research device located in Hefei, China.
  • It is one of three major domestic tokamaks that are presently being operated across the country.
  • The EAST project is part of the International Thermonuclear Experimental Reactor (ITER) facility, which will become the world’s largest nuclear fusion reactor when it becomes operational in 2035.
  • The ITER project includes the contributions of several countries, including India, South Korea, Japan, Russia, and the United States.

How does the ‘artificial sun’ EAST work?

  • It replicates the nuclear fusion process carried out by the sun and stars.
  • For nuclear fusion to occur, tremendous heat and pressure are applied to hydrogen atoms so that they fuse.
  • The nuclei of deuterium and tritium — both found in hydrogen — are made to fuse to create a helium nucleus, a neutron along a whole lot of energy.
  • Here, fuel is heated to temperatures of over 150 million degrees C so that it forms a hot plasma “soup” of subatomic particles.
  • With the help of a strong magnetic field, the plasma is kept away from the walls of the reactor to ensure it does not cool down and lose its potential to generate large amounts of energy. The plasma is confined for long durations for fusion to take place.

Why is fusion better than fission?

  • While fission is an easier process to carry out, it generates far more nuclear waste.
  • Once mastered, nuclear fusion could potentially provide unlimited clean energy and very low costs.
  • Like fission, fusion also does not emit greenhouse gases and is considered a safer process with a lower risk of accidents.

Which other countries have achieved this feat?

  • China is not the only country that has achieved high plasma temperatures. In 2020, South Korea’s KSTAR reactor set a new record by maintaining a plasma temperature of over 100 million degrees Celsius for 20 seconds. 

MARITIME ZONES

Context:

  • Illegal fishing: 88 Bangladeshis intercepted by ICG(Indian Coast Guard).
  • The maritime boundary dispute(Sir creek issue) between India and Pakistan in the Gulf of Kutch region.

About:

  • Baseline – It is the low-water line along the coast as officially recognized by the coastal state.
  • Internal Waters:
    • Internal waters are waters on the landward side of the baseline from which the breadth of the territorial sea is measured.
    • Each coastal state has full sovereignty over its internal waters as like its land territory. Examples of internal waters include bays, ports, inlets, rivers, and even lakes that are connected to the sea.
    • There is no right to innocent passage through internal waters. The innocent passage refers to the passing through the waters which are not prejudicial to peace and security. However, the nations have the right to suspend the same.
  • Territorial Sea:
    • The territorial sea extends seaward up to 12 nautical miles (nm) from its baselines.
    • The coastal states have sovereignty and jurisdiction over the territorial sea. These rights extend not only on the surface but also to the seabed, subsoil, and even airspace.
    • But the coastal state's rights are limited by the innocent passage through the territorial sea.
  • Contiguous Zone:
    • The contiguous zone extends seaward up to 24 nm from its baselines.
    • It is an intermediary zone between the territorial sea and the high seas.
    • The coastal state has the right to both prevent and punish infringement of fiscal, immigration, sanitary, and customs laws within its territory and territorial sea.
    • Unlike the territorial sea, the contiguous zone only gives jurisdiction to a state on the ocean’s surface and floor. It does not provide air and space rights.
  • Exclusive Economic Zone (EEZ):
    • Each coastal State may claim an EEZ beyond and adjacent to its territorial sea that extends seaward up to 200 nm from its baselines.
    • Sovereign rights to explore, exploit, conserve, and manage natural resources, whether living or nonliving, of the seabed and subsoil.
    • Rights to carry out activities like the production of energy from the water, currents, and wind.
    • Unlike the territorial sea and the contiguous zone, the EEZ only allows for the above-mentioned resource rights. It does not give a coastal state the right to prohibit or limit freedom of navigation or overflight, subject to very limited exceptions.
  • High Seas:
    • The ocean surface and the water column beyond the EEZ are referred to as the high seas.
    • It is considered the common heritage of all mankind and is beyond any national jurisdiction.
    • States can conduct activities in these areas as long as they are for peaceful purposes, such as transit, marine science, and undersea exploration.

Seafloor Spreading

Context:

  • Study shows the pace of seafloor spreading has slowed down by roughly 35% globally.

Key Findings of the Study:

  • The seafloor is spreading at the rate of around 140 millimetres per year, down from around 200 millimetres per year compared to 15 million years ago in some places.
  • The speed of movements was pronounced at ridges along the eastern Pacific.
  • Certain ridges in the region were roughly 100 millimetres per year slower compared to 19 million years ago, lowering the world’s average.
  • The factor driving the slowdown could be located in subduction zones rather than the ridges.

About Seafloor Spreading:

  • The seafloor spreading hypothesis was proposed by the American geophysicist Harry H. Hess in 1960. It is a
  • geologic process in which tectonic plates large slabs of Earth's lithosphere split apart from each other.

Process of Seafloor Spreading:

  • This process is the result of mantle convection. Mantle convection is the slow, churning motion of Earth’s mantle. It occurs at divergent plate boundaries.
  • As tectonic plates slowly move away from each other, heat from the mantle’s convection currents makes the crust more plastic and less dense.
  • The less-dense material rises, often forming a mountain or elevated area of the seafloor.
  • Eventually, the crust cracks. Hot magma fuelled by mantle convection bubbles up to fill these fractures and spills onto the crust.
  • This bubbled-up magma is cooled by frigid seawater to form igneous rock. This rock (basalt) becomes a new part of Earth’s crust.

Evidences of Seafloor Spreading:

  • Molten material: The condition on the mid-oceanic ridge is substantially different from other surfaces away from the region because of the warmer temperature. The molten magma from the mantle arose due to the convection currents in the interior of the earth.
  • Seafloor drill: The samples obtained from the seafloor drill reveals that the rocks away from the mid-oceanic ridge were relatively older than the rocks near to it. The old rocks were also denser and thicker compared to the thinner and less dense rocks in the mid-oceanic ridge.
  • Radiometric age dating and fossil ages: By the use of radiometric age dating and studying fossil ages, it was also found out the rocks of the sea floorage is younger than the continental rocks. It is believed that continental rocks formed 3 billion years ago, however the sediment samples from the ocean floor are found to be not exceeding 200 million years old.
  • Magnetic stripes: By using the magnetometer, the magnetic polarity will be shown through a timescale that contains the normal and reverse polarity. The minerals contained in the rocks are oriented opposite to the magnetic field. The patterns of the magnetic field will then be compared to the rocks to determine its approximate ages.

Reasons behind the Decline of Seafloor Spreading:

  • Growing mountains on the continents might be one of the factors driving the slowdown as it causes resistance to seafloor spreading.
  • As Pangea progressively broke apart, new ocean basins formed and eventually, the widely fragmented continents started running into each other.
  • Changes in mantle convection could also be playing a role as mantle convection transports heat from the earth’s interior to the surface.

Why is the pace of Seafloor Spreading important?

  • This is important because it affects sea levels and the carbon cycle on Earth.
  • Faster movement means more volcanic activity and more new crustal formations.
  • It also injects greenhouse gases into the atmosphere which has a great impact on the Earth's atmosphere.
  • The basaltic rocks formed as a result of this process have magnetic properties. This magnetism is affected by the Earth's magnetic field.
  • It is also important from the point of view of marine life on the ocean floor.

Karewas

Context:

  • In the name of development, Kashmir’s highly fertile alluvial soil deposits called ‘karewas’ are being destroyed.

About:

Karewas:

  • Karewas are lacustrine deposits (deposits in the lake) in the Valley of Kashmir and in Bhadarwah Valley of the Jammu Division.
  • These are the flat-topped mounds that border the Kashmir Valley on all sides.

How are Karewas formed?

  • Karewas were formed during the Pleistocene Period (1 million years ago) when the entire Valley of Kashmir was underwater.
  • Due to the rise of Pir Panjal, the drainage was impounded and a lake of about 5000 sq. km area was developed thus a basin was formed.
  • Subsequently, the lake was drained through Bramulla gorge. The deposits left in the process are known as karewas.

What is the significance of Karewas?

  • Karewas are 13,000-18,000 metre-thick deposits of alluvial soil and sediments like sandstone and mudstone.
  • This makes them ideal for the cultivation of saffron, almonds, apples and several other cash crops.
  • Kashmir saffron, which received a Geographical Indication (GI) tag in 2020 for its longer and thicker stigmas, deep-red colour, high aroma and bitter flavour, is grown on these karewas.
  • However, despite its agricultural and archaeological importance, karewas are now being excavated to be used in construction.
  • Between 1995 and 2005, massive portions of karewas were razed to the ground for clay for the QazigundBaramulla rail line. The Srinagar airport is built on the Damodar karewa.

IMPORTANT RIVERS IN THE NEWS

Par Tapi Narmada link project

Context:

  • On March 21, 2022, the tribals in Gujarat will hold a public meeting in Kaprada in Valsad district to protest against the Centre’s Par Tapi Narmada river-linking project.

About:

  • Envisioned under the 1980 National Perspective Plan under the former Union Ministry of Irrigation and the Central Water Commission (CWC).
  • The project proposes to transfer river water from the surplus regions of the Western Ghats to the deficit regions of Saurashtra and Kutch.
  • The excess water in the interlinked Par, Tapi and Narmada rivers which flow into the sea in the monsoon would be diverted to Saurashtra and Kutch for irrigation.
  • It proposes to link three rivers — Par, which originates from Nashik in Maharashtra and flows through Valsad, Tapi from Saputara which flows through Maharashtra and Surat in Gujarat, and Narmada originating in Madhya Pradesh and flowing through Maharashtra and Bharuch and Narmada districts in Gujarat.
  • The link mainly includes the construction of:  seven dams (Jheri, Mohankavchali, Paikhed, Chasmandva, Chikkar, Dabdar and Kelwan),
  • three diversion weirs (Paikhed, Chasmandva, and Chikkar dams),
  • two tunnels (5.0 kilometres and 0.5 kilometres length),
  • the 395-kilometre long canal (205 kilometres in the Par-Tapi portion including the length of feeder canals and 190 km in the Tapi-Narmada portion), and six powerhouses.
  • Of these, the Jheri dam falls in Nashik, while the remaining dams are in Valsad and Dang districts of South Gujarat.

Pranahita River

Context:

  • Maha Harathi and other special rituals marked the grand finale of the 12-day Pranahita river festival. The mega river festival is dedicated to worshipping the Pranahita

About:

  • It is a perennial river, which flows along the border of Maharashtra and Telangana.
  • It is the largest tributary of the Godavari River.
  • The tributaries are Mamda, Nagul vagu, Wil Vagu, Pedda Vagu, Madharam, Bamar, Dongri, Patra.
  • Due to its extensive network of tributaries, the river drains a large part of the Vidarbha region in Maharashtra as well as the southern slopes of the Satpura range in southeast Madhya Pradesh.
  • Its sub-basin is the seventh-largest in India.

Indus river:

  • The ancient name is Sindhu and origin from Bokharchu Glacier, Near Mansarovar
  • Enters In India through Ladakh, flows only in J &K. Enters Pak through the hairpin bend of Nanga Parbat. Finally Discharges in the Arabian Sea.
  • After entering J&K it flows between the Ladakh and the Zaskar Ranges. It flows through the regions of Ladakh, Baltistan, and Gilgit.
  • India uses 20 % of its water by the Indo-Pak water treaty of 1960.
  • Zaskar river, Suru river, Soan river, Jhelum River, Chenab River, Ravi River, Beas river, Satluj river, Panjnad river are its major left-bank tributaries.
  • Shyok River, Gilgit river, Hunza river, Swat river, Kunar river, Kurram river, Gomal River, and Kabul river are its major right-bank tributaries. 

Umngot River

  • Umngot River is the cleanest river in India and in some parts is as transparent as crystal and you can actually see the river bed.
  • Umngot River, which flows in both India and Bangladesh, is in Meghalaya
  • The river is the natural boundary between Ri Pnar (of Jaintia Hills) with Hima Khyrim (of Khasi Hills) over which hangs a single-span suspension bridge.

Pangong Tso

  • Pangong Tso is an endorheic lake (landlocked) that is partly in India’s Ladakh region and partly in Tibet.
  • Nearly two-thirds of the lake is controlled by China, with just about 45 km under Indian control. The LAC, running north-south, cuts the western part of the lake, aligned east-west.
  • Situated at an elevation of about 4,270 m, it is a nearly 135-km long, narrow lake — 6 km at its widest point — and shaped like a boomerang
  • The lake’s water, while crystal clear, is brackish, making it undrinkable. The lake freezes during the winter, allowing some vehicular movement on it as well.
  • Cauvery River
    • The Cauvery River (Kaveri) is designated as the Dakshina Ganga or the Ganga of the South.
    • The Cauvery River rises at an elevation of 1,341 m at Talakaveri on the Brahmagiri range near Cherangala village of Kodagu (Coorg) district of Karnataka.
    • Left Bank: the Harangi, the Hemavati, the Shimsha, and the Arkavati.
    • Right Bank: Lakshmantirtha, the Kabbani, the Suvarnavati, the Bhavani, the Noyil, and the Amaravati joins from the right.
    • A tributary called Bhavani joins Cauvery on the Right bank about 45 Kms below Mettur Reservoir. Thereafter it enters the plains of Tamil Nadu.
    • Two more tributaries Noyil and Amaravathi join on the right bank and here the river widens with a sandy bed and flows as Akhanda Cauvery.

Krishna River:

  • The Krishna River is the second biggest river in peninsular India after the Godavari River.
  • It originates near Mahabaleshwar (Satara) in Maharashtra.
  • It runs from four states Maharashtra (303 km), North Karnataka (480 km) and the rest of its 1300 km journey in Telangana and Andhra Pradesh before it empties into the Bay of Bengal.
  • Tributaries: Tungabhadra, Mallaprabha, Koyna, Bhima, Ghataprabha, Yerla, Warna, Dindi, Musi and Dudhganga.
  • Pattiseema Lift Irrigation project is the first river-linking project in India, connecting Godavari with Krishna through the Polavaram right canal. It will divert surplus Godavari water to the Krishna river.

Ganga River System

  • The Ganga is formed from the 6 headstreams and their five confluences.
  • The Alaknanda River meets the Dhauliganga River at Vishnuprayag, the Nandakini River at Nandprayag, the Pindar River to form the Ganga mainstream.
  • The Bhagirathi, considered to be the source stream: rises at the foot of Gangotri Glacier, at Gaumukh, at an elevation of 3892m and fanning out into the 350km wide Ganga delta, it finally empties into the Bay of Bengal.
  • From Devapryag the river is called Ganga.
  • Ganga debouches [emerge from a confined space into a wide, open area] from the hills into the plain area at It is joined by the Yamuna at Allahabad.
  • Near Rajmahal Hills it turns to the southeast.
  • At Farraka, it bifurcates into Bhagirathi-Hugli in West Bengal and Padma-Meghna in Bangladesh (it ceases to be known as the Ganga after Farraka).
  • Brahmaputra (or the Jamuna as it is known here) joins Padma-Meghna.
  • The total length of the Ganga river from its source to its mouth (measured along the Hugli) is 2,525 km.
  • Haridwar, Kanpur, Soron, Kannauj, Allahabad, Varanasi, Patna, Ghazipur, Bhagalpur, Mirzapur, Ballia, Buxar, Saidpur, and Chunar are the important towns.
  • It has long been considered holy by Hindus and worshipped as the goddess Ganga in Hinduism.



Please Share with maximum friends to support the Initiative.

Enquire now

Give us a call or fill in the form below and we will contact you. We endeavor to answer all inquiries within 24 hours on business days.