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Subject: Environment

  • Peatlands and their importance

    Sustainably managing peatlands — peat-swamp forests found around the tropics — can protect humans from future pandemics, according to a new study.

    What are Peatlands?

    • Peatlands are terrestrial wetland ecosystems in which waterlogged conditions prevent plant material from fully decomposing.
    • Consequently, the production of organic matter exceeds its decomposition, which results in a net accumulation of peat.
    • Over millennia this material builds up and becomes several metres thick.
    • They occur in almost every country on Earth, currently covering 3% of the global land surface.
    • Peatland landscapes are varied – from blanket bog landscapes with open, treeless vegetation in the Flow Country of Scotland – a tentative World Heritage site – to swamp forests in Southeast Asia.

    Their importance

    • Peatlands are the largest natural terrestrial carbon store. This area sequesters 0.37 gigatonnes of CO2 a year.
    • In their natural, wet state peatlands provide vital ecosystem services.
    • By regulating water flows, they help minimise the risk of flooding and drought and prevent seawater intrusion.
    • In many parts of the world, peatlands supply food, fibre and other local products that sustain local economies.
    • They also preserve important ecological and archaeological information such as pollen records and human artefacts.

    Try this PYQ now:

    In the context of mitigating the impending global warming due to anthropogenic emission of carbon dioxide, which of the following can be the potential sites for carbon sequestration?

    1. Abandoned and Uneconomic coal seams
    2. Depleted oil and gas reservoirs
    3. Subterranean deep saline formations

    Select the correct answer using the code given below:

    (a) 1 and 2 only

    (b) 1 and 3 only

    (c) 3 only

    (d) 1, 2 and 3

    Why conserve peatlands?

    • The protection and restoration of peatlands are vital in the transition towards a low-carbon and circular economy.
    • Damaged peatlands contribute about 10% of greenhouse gas emissions from the land-use sector.
    • CO2 emissions from drained peatlands are estimated at 1.3 gigatonnes of CO2 annually.
    • This is equivalent to 5.6% of global anthropogenic CO2 emissions.
    • Draining peatlands reduces the quality of drinking water due to pollution from dissolved compounds.

    What is the new study?

    • Peatlands were rich in biodiversity, including many potential vertebrate and invertebrate vectors, or carriers of disease, the study said.
    • These included numerous vertebrates known to represent a risk of spreading zoonotic diseases, such as bats, rodents, pangolins and primates.
    • These areas also faced high levels of habitat disruption such as wild or human-made fires and wildlife harvesting that was perfect conditions for potential emerging zoonotic diseases.
    • The first reported case of Ebola in 1976 was from a peatland area.
    • The cradle of the HIV/AIDS pandemic was believed to be around Kinshasa in the Democratic Republic of the Congo, another area with extensive peatlands.
  • Western Disturbances and winters in North

    For the past few days, Chandigarh and its neighbouring states have been experiencing unusually cold days although the night temperatures are normal.

    Try this PYQ:

    Consider the following statements:

    1. The winds which blow between 30°N and 60°S latitudes throughout the year are known as westerlies.
    2. The moist air masses that cause winter rains in the North-Western region of India are part of westerlies.

    Which of the statements given above is/are correct?

    (a) Only 1

    (b) Only 2

    (c) Both 1 and 2

    (d) Neither 1 nor 2

    Temperature anomaly in North

    • Meteorological officials have attributed the trend to the cloud cover in the region which was absent until a few days ago.
    • It is the result of a western disturbance, which has brought about a spell of precipitation in the northwest Himalaya.

    Role of clouds

    • During the day, clouds obstruct the heat from the sun from reaching the surface of the earth, reflecting some of it back into space.
    • This lowers the temperature. Cold winds blowing down from snow-bound areas in the mountains also contribute to the cooling effect.
    • At night, however, clouds act like blankets – they help retain some of the heat energy radiated back by the earth’s surface.
    • Overcast weather at night, thus, increases greenhouse warming.

    What are western disturbances?

    • In northern India, winter rains and clouds are generally caused by moisture-bearing wind systems called western disturbances.
    • They originate and gather moisture over the Mediterranean region and flow eastwards towards the Indian subcontinent.
    • When some of these winds run into mountains of the northwest Himalaya, they are forced upward.
    • At higher altitudes, the temperatures drop and water vapour gets condensed. This leads to cloud formation and eventually rain and snow.

    Other factors for severe winters in North

    • In north India, the huge temperature difference between summers and winters is due to its continentality (distance from seas and oceans).
    • Air from oceans moderates the temperature as it moves onshore, but this effect is missing in continental interiors.
    • As a result, north India has greater seasonal differences as compared to peninsular India.
    • Temperature also reduces rapidly with altitude, and thus, the Himalayan region is colder still.
  • Why has the Northeast Monsoon remained deficient this year?

    Rainfall over the Southern peninsular region has been deficient so far due to prevailing La Nina conditions according to the India Meteorological Department (IMD).

    Try this PYQ:

    Q.La Nina is suspected to have caused recent floods in Australia. How is La Nina different from El Nino?

    1. La Nina is characterized by unusually cold ocean temperature in equatorial Indian Ocean whereas El Nino is characterized by unusually warm ocean temperature in the equatorial Pacific Ocean.
    2. El Nino has an adverse effect on south-west monsoon of India, but La Nina has no effect on monsoon climate.

    Which of the statements given above is/are correct?

    (a) Only 1

    (b) Only 2

    (c) Both 1 and 2

    (d) Neither 1 nor 2

    What is the Northeast monsoon?

    • India receives rainfall during two seasons.
    • About 75 per cent of the country’s annual rainfall is received from the Southwest monsoon between June and September.
    • The Northeast monsoon, on the other hand, occurs from October to December and is a comparatively small-scale monsoon, which is confined to the Southern peninsula.
    • After the complete withdrawal of the Southwest monsoon from the country takes place by mid-October, the wind pattern rapidly changes from the south-westerly to the north-easterly direction.
    • Also called the winter monsoon, the rainfall associated with the Northeast monsoon is important for almost entire South India.

    Why it is important?

    • Tamil Nadu records about 48 per cent (447.4 mm) of its annual rainfall (943.7 mm) during these months, making it the key factor for undertaking agricultural activities and reservoir management in the state.
    • Some South Asian countries such as Maldives, Sri Lanka and Myanmar also record rainfall from October to December.

    Why there are distortions?

    • The majority of districts in Tamil Nadu remain highly rain-deficient up this time.
    • The period after the Southwest monsoon season, from October to December, is the peak time for cyclonic activity in the North Indian Ocean region — covering the Arabian Sea and the Bay of Bengal.
    • The winds associated with the formation of low-pressure systems, depressions, or cyclones influence this monsoon, and therefore, the rainfall.
    • Officials at IMD have linked it to the prevailing La Niña conditions in the Pacific Ocean.

    La Nina  link with the NE monsoon

    • While La Niña conditions enhance the rainfall associated with the Southwest monsoon, it has a negative impact on rainfall associated with the Northeast monsoon.
    • During La Niña years, the synoptic systems — low pressure or cyclones — formed in the Bay of Bengal remain significantly to the north of their normal position.
    • Besides, instead of moving westwards, these systems recurve. As they lie to the north of their normal position, not much rainfall occurs over southern regions like Tamil Nadu.

    Back2Basics: El Nino and La Nina

    • While El Niño (Spanish for ‘little boy’), the more common expression, is the abnormal surface warming observed along the eastern and central regions of the Pacific Ocean (the region between Peru and Papua New Guinea).
    • The La Niña (Spanish for ‘little girl’) is an abnormal cooling of these surface waters.
    • Together, the El Niño and La Niña phenomena are termed as El Niño Southern Oscillation (ENSO).
    • These are large-scale ocean phenomena which influence the global weather — winds, temperature and rainfall. They have the ability to trigger extreme weather events like droughts, floods, hot and cold conditions, globally.
    • Each cycle can last anywhere between 9 to 12 months, at times extendable to 18 months — and re-occur after every three to five years.
    • Meteorologists record the sea surface temperatures for four different regions, known as Niño regions, along this equatorial belt.
    • Depending on the temperatures, they forecast either as an El Niño, an ENSO neutral phase, or a La Niña.
  • Desalination Plants and their Feasibility

    Maharashtra state govt. has announced the setting up of a desalination plant in Mumbai, becoming the fourth state in the country to experiment with the idea.

    Try this PYQ:

    Q.What is the role of ultraviolet (UV) radiation in the water purification systems?

    1. It inactivates/kills the harmful microorganisms in water.
    2. It removes the entire undesirable odour from the water.
    3. It quickens the sedimentation of solid particles, removes turbidity and improves the clarity of water.

    Which of the statements given above is/are correct?

    (a) 1 only

    (b) 2 and 3 only

    (c) 1 and 3 only

    (d) 1, 2 and 3

    What are Desalination Plants?

    • A desalination plant turns salt water into water that is fit to drink.
    • The most commonly used techniques used for the process is reverse osmosis where external pressure is applied to push solvents from an area of high-solute concentration to an area of low-solute concentration through a membrane.
    • The microscopic pores in the membranes allow water molecules through but leave salt and most other impurities behind, releasing clean water from the other side.
    • These plants are mostly set up in areas that have access to seawater.

    How widely is this technology used in India?

    • Desalination has largely been limited to affluent countries in the Middle East and has recently started making inroads in parts of the United States and Australia.
    • In India, Tamil Nadu has been the pioneer in using this technology, setting up two desalination plants near Chennai in 2010 and then 2013, while there are two more to come.

    Need for such plant

    • According to the projections, the population of Mumbai is anticipated to touch 1.72 crores by 2041 and accordingly, the projected water demand would be 6424 MLD by then.
    • Currently, BMC supplies 3850 MLD as against the requirement of 4200 MLD each day.

    Is it ecologically safe?

    • The high cost of setting up and running a desalination plant is one reason why the Maharashtra government has over the last decade been hesitant in building such a plant.
    • Desalination is an expensive way of generating drinking water as it requires a high amount of energy.
    • The other problem is the disposal of the byproduct — highly concentrated brine (saltwater) — of the desalination process.
    • While in most places brine is pumped back into the sea, there have been rising complaints that it ends up severely damaging the local ecology around the plant.

    Back2Basics: Osmosis and Reverse Osmosis

    • Osmosis is a phenomenon where pure water flows from a dilute solution through a semi-permeable membrane to a higher concentrated solution.
    • Semi-permeable means that the membrane will allow small molecules and ions to pass through it but acts as a barrier to larger molecules or dissolved substances.
    • As water passes through the membrane to the salt solution, the level of liquid in the saltwater compartment will rise until enough pressure, caused by the difference in levels between the two compartments, is generated to stop the osmosis.
    • This pressure, equivalent to a force that the osmosis seems to exert in trying to equalize concentrations on both sides of the membrane, is called osmotic pressure.
    • If pressure greater than the osmotic pressure is applied to the high concentration the direction of water flow through the membrane can be reversed.
    • This is called reverse osmosis. Note that this reversed flow produces pure water from the salt solution since the membrane is not permeable to salt.
  • What are Miyawaki Forests?

    Japan-inspired Miyawaki forests are emerging as a popular solution to restoring degraded habitats in the country.

    Try this question:

    Q.The Miyawaki Forests technique has to potential to revolutionize the concept of urban afforestation in India. Discuss.

    Miyawaki Forests

    • Doctor Akira Miyawaki, botanist and professor, is the inventor of the technique since 1980.
    • He is a recipient of the 2006 Blue Planet Prize, which is the equivalent of a Nobel Prize in ecology.
    • The approach is supposed to ensure that plant growth is 10 times faster and the resulting plantation is 30 times denser than usual.
    • It involves planting dozens of native species in the same area and becomes maintenance-free after the first three years.

    The technique

    • The method takes its inspiration directly from processes and diversity in nature: 15 to 30 different species of trees and shrubs are planted together.
    • This plant community works very well together and is perfectly adapted to local weather conditions.
    • The habitat thus created will get more complex over time and attract much biodiversity.
    • Vegetation becomes much denser than conventional plantations, and it has the structure of a mature natural forest. It is a multi-storey structure, where different levels of vegetation appear.
    • The forest thus structured delivers many benefits in the form of ecosystem services.
    • It would take about 200 years to let a forest recover on its own. With the Miyawaki method, a similar result is achieved in 20 years.
  • Cyclone Nivar to make landfall in TN

    A developing cyclonic disturbance in the Bay of Bengal is expected to become a ‘severe cyclonic storm’ and make landfall in Tamil Nadu.

    Cyclone Nivar

    • The IMD has forecasted the development of a cyclone in the Southwest region of the Bay of Bengal, off Tamil Nadu coast.
    • It has said that it will strengthen into a cyclone. Once intensified, it would acquire its name ‘Nivar’, proposed by Iran.
    • After cyclone Gaja in 2018, this will be the second cyclone to cross Tamil Nadu in the last two years.

    Try this PYQ:

    In the South Atlantic and South-Eastern Pacific regions in tropical latitudes, cyclone does not originate. What is the reason?

    (a) Sea surface temperatures are low

    (b) Inter-Tropical Convergence Zone seldom occurs

    (c) Coriolis force is too weak

    (d) Absence of land in those regions

    Tropical Cyclone

    • A Tropical cyclone is an intense circular storm that originates over warm tropical oceans and is characterized by low atmospheric pressure, high winds, and heavy rain.
    • Cyclones are formed over slightly warm ocean waters. The temperature of the top layer of the sea, up to a depth of about 60 meters, need to be at least 28°C to support the formation of a cyclone.
    • This explains why the April-May and October-December periods are conducive for cyclones.
    • Then, the low level of air above the waters needs to have an ‘anticlockwise’ rotation (in the northern hemisphere; clockwise in the southern hemisphere).
    • During these periods, there is an ITCZ in the Bay of Bengal whose southern boundary experiences winds from west to east, while the northern boundary has winds flowing east to west.
    • Once formed, cyclones in this area usually move northwest. As it travels over the sea, the cyclone gathers more moist air from the warm sea which adds to its heft.

    Must read:

    [Burning Issue] Tropical Cyclones and India

  • Places in news: Mount Vesuvius

    The Italian Culture Ministry announced the discovery of well-preserved remains of two men, who perished during the volcanic eruption of Mount Vesuvius in 79 AD.

    Try this PYQ:

    Q.Consider the following statements:

    1. The Barren Island volcano is an active volcano located in the Indian Territory.
    2. Barren Island lies about 140 km east of Great Nicobar.
    3. The last time the Barren Island volcano erupted was in 1991 and it has remained inactive since then.

    Which of the statements given above is/are correct?

    (a) 1 only

    (b) 2 and 3 only

    (c) 3 only

    (d) 1 and 3 only

    Mount Vesuvius

    • Located in southern Italy near the coastal city of Naples, the 4,203-ft (1,281 metres) tall Vesuvius is the only active volcano in mainland Europe.
    • Vesuvius has been classified as a complex volcano (also called a compound volcano), one that consists of a complex of two or more vents.
    • It typically has explosive eruptions and pyroclastic flows –– defined as a high-density mix of hot lava blocks, pumice, ash and volcanic gas.
    • It has erupted more than 50 times and is considered among the most dangerous volcanoes in the world due to its proximity to Naples and surrounding towns.
    • Its last serious eruption, lasting two weeks, was in 1944 during World War II, which left 26 Italian civilians dead and around 12,000 displaced.

    The eruption of 79 AD

    • In 79 AD, the Roman Empire-era sister cities of Pompeii and Herculaneum were destroyed and buried during a catastrophic eruption of Vesuvius.
    • It was a catastrophic event that destroyed the ancient Roman city of Pompeii and killed around 16,000 people.
    • Pompeii, 8 km away from Vesuvius, served as a resort town on the Bay of Naples for Rome’s elite citizens, consisting of villas, cafes, marketplaces and a 20,000-seat arena.
    • In 63 AD, a major earthquake rattled the city, serving as a warning for the eruption to come. However, few residents bothered to abandon the region, known for its volatility.
  • Chinese dam projects on Brahmaputra and impact on downstream countries

    Scarcity of water in India and China

    • As India and China continue to grow demographically as well as economically amid increased consumption among its citizenry, both nations face water constraints.
    • China, which is home to close to 20 per cent of the world’s population, has only 7 per cent of its water resources.
    • Severe pollution of its surface and groundwater caused by rapid industrialisation is a source of concern for Chinese planners.
    • China’s southern regions are water-rich in comparison to the water-stressed northern part.
    • The southern region is a major food producer and has significant industrial capacity as a consequence of more people living there.
    • India is severely water-stressed as well.
    • Similar to China, India has 17 per cent of the world’s population and 4 per cent of water.
    • As in China, an equally ambitious north-south river-linking project has been proposed in India.

    Impact on downstream states

    • The construction of several dams along the Yarlung (Brahmaputra) river on the Chinese side has been a repeated cause for concern for Indian officials and the local people.
    • China has an ambitious plan to link its south and north through canals, aqueducts and linking of major rivers to ensure water security.
    • In pursuit of these goals, China, being an upper riparian state in Asia, has been blocking rivers like the Mekong and its tributaries, affecting Southeast Asian countries like Thailand, Vietnam, Laos and Cambodia.
    • It has caused immense damage to the environment and altered river flows in the region.
    • China sees these projects as a continuation of their historic tributary system as the smaller states have no means of effectively resisting or even significant leverage in negotiations.

    Challenges for India

    • There are now multiple operational dams in the Yarlung Tsangpo basin with more dams commissioned and under construction. These constructions present a unique challenge for Indian planners.
    • 1) Dams will eventually lead to degradation of the entire basin:
    • Silt carried by the river would get blocked by dams leading to a fall in the quality of soil and eventual reduction in agricultural productivity.
    • 2) The Brahmaputra basin is one of the world’s most ecologically sensitive zones.
    • It is identified as one of the world’s 34 biological hotspots.
    • This region sees several species of flora and fauna that are endemic to only this part of the world.
    • The river itself is home to the Gangetic river dolphin, which is listed as critically endangered.
    • 3) The location of the dams in the Himalayas pose a risk.
    • Seismologists consider the Himalayas as most vulnerable to earthquakes and seismic activity.
    • The sheer size of the infrastructure projects undertaken by China, and increasingly by India, poses a significant threat to the populations living downstream.
    • Close to a million people live in the Brahmaputra basin in India and tens of millions further downstream in Bangladesh.
    • 4) Damming Brahmaputra would result in water security in an era of unprecedented shifting climate patterns.
    • This security extends beyond water, as there is the potential to significantly change the flow rate during times of standoffs and high tensions.

    Way forward

    • Both sides must cease new constructions on the river and commit to potentially less destructive solutions.
    • Building a decentralised network of check dams, rain-capturing lakes and using traditional means of water capture have shown effective results in restoring the ecological balance while supporting the populations of the regions in a sustainable manner.

    Conclusion

    There are alternate solutions to solving the water crisis.  It is in the interest of all stakeholders to neutralise this ticking water bomb.

  • Understanding the interplay between subsidies and agri-pollution

    Agriculture’s contribution to air pollution

    • Agriculture’s contribution to air pollution runs deeper than what happens between crop seasons.
    • The Indo-Gangetic plain is also one of the world’s largest and rapidly-growing ammonia hotspots.
    • Atmospheric ammonia, which comes from fertiliser use, animal husbandry, and other agricultural practices, combines with emissions from power plants, transportation and other fossil-fuel burning to form fine particles.

    Impact of pollution on agriculture

    • It is important to note that agriculture is a victim of pollution as well as its perpetrator.
    • Particulate matter and ground-level ozone formed from industrial, power plant, and transportation emissions among other ingredients cause double-digit losses in crop yields.
    • Ozone damages plant cells, handicapping photosynthesis, while particulate matter dims the sunlight that reaches crops.
    • Agriculture scientist Tony Fischer’s 2019 estimates of the two pollutants’ combined effect suggest that as much as 30 per cent of India’s wheat yield is missing (Sage Journals, Outlook on Agriculture).
    • Earlier, B Sinha et al (2015), in Atmospheric Chemistry and Physics Discussions, found that high ozone levels in parts of Haryana and Punjab could diminish rice yields by a quarter and cotton by half.

    Role played by subsidies

    • The current system of subsidies is a big reason that there is stubble on these fields in the first place.
    • Free power — and consequently, “free” water, pumped from the ground — is a big part of what makes growing rice in these areas attractive.
    • Open-ended procurement of paddy, despite the bulging stocks of grains with the Food Corporation of India, adds to the incentives.
    • Subsidies account for almost 15 per cent of the value of rice being produced in Punjab-Haryana belt.
    • Fertiliser, particularly urea in granular form, is highly subsidised.
    • It is one of the cheapest forms of nitrogen-based fertiliser, easy to store and easy to transport, but it is also one of the first to “volatilise,” or release ammonia into the air.
    • This loss of nitrogen then leads to a cycle of more and more fertiliser being applied to get the intended benefits for crops.

    Way forward

    • We need to shift the nature of support to farmers from input subsidies to investment subsidies.
    • This could involve the conversion of paddy areas in this belt to orchards with drip irrigation, vegetables, corn, cotton, pulses and oilseeds.
    • All of the above consume much less water, much less power and fertilisers and don’t create stubble to burn.
    • A diversification package of, say, Rs 10,000 crore spread over the next five years, equally contributed by the Centre and states, may be the best way to move forward in reducing agriculture-related pollution.
    • The approach to diversification has to be demand-led, with a holistic framework of the value chain, from farm to fork and not just focused on production.
    • On the fertiliser front, it would be better to give farmers input subsidy in cash on per hectare basis, and free up the prices of fertilisers completely.

    Conclusion

    Taken together, these measures could double farmers’ incomes, promote efficiency in resource use, and reduce pollution — a win-win solution for all.

  • India’s Deep Ocean Mission

    India will soon launch an ambitious ‘Deep Ocean Mission’ that envisages exploration of minerals, energy and marine diversity of the underwater world, a vast part of which still remains unexplored.

    Deep Ocean Mission (DOM)

    Nodal Agency: Ministry of Earth Sciences (MoES)

    • The mission proposes to explore the deep ocean similar to the space exploration started by ISRO.
    • Underwater robotics and ‘manned’ submersibles are key components of the Mission which will help India harness various living and non-living (water, mineral and energy) resources from the seabed and deep water.
    • The tasks that will be undertaken over this period include deep-sea mining, survey, energy exploration and the offshore-based desalination.
    • These technological developments are funded under an umbrella scheme of the government – called Ocean Services, Technology, Observations, Resources Modelling and Science (O-SMART).

     Mining PMN

    • One of the main aims of the mission is to explore and extract polymetallic nodules (PMN).
    • These are small potato-like rounded accretions composed of minerals such as manganese, nickel, cobalt, copper and iron hydroxide.
    • They lie scattered on the Indian Ocean floor at depths of about 6,000 m and the size can vary from a few millimetres to centimetres.
    • These metals can be extracted and used in electronic devices, smartphones, batteries and even for solar panels.

    Where will the team mine?

    • The International Seabed Authority (ISA), an autonomous international organisation established under the 1982 United Nations Convention on the Law of the Sea, allots the ‘area’ for deep-sea mining.
    • India was the first country to receive the status of a ‘Pioneer Investor ‘ in 1987 and was given an area of about 1.5 lakh sq km in the Central Indian Ocean Basin (CIOB) for nodule exploration.
    • In 2002, India signed a contract with the ISA and after complete resource analysis of the seabed 50% was surrendered and the country retained an area of 75,000 sq km.

    Which are the other countries that are in the race to mine the deep sea?

    • Apart from the CIOB, polymetallic nodules have been identified from the central Pacific Ocean. It is known as the Clarion-Clipperton Zone.
    • According to the ISA’s website, it has entered into 15-year contracts for exploration for polymetallic nodules, polymetallic sulphides and cobalt-rich ferromanganese crusts in the deep seabed with 29 contractors.
    • Later it was extended for five more years till 2022.
    • China, France, Germany, Japan, South Korea, Russia and also some small islands such as the Cook Islands, Kiribati have joined the race for deep-sea mining.
    • Most of the countries have tested their technologies in shallow waters and are yet to start deep-sea extraction.

    India’s preparedness

    • India’s mining site is at about a depth of 5,500 metres, where there is a high pressure and extremely low temperature.
    • We have also deployed Remotely Operated Vehicle and In-situ Soil Tester in the depth of 6,000 metres and have a thorough understanding of the mining area at the Central Indian Ocean Basin.
    • The mining machine newly developed for 6000 metres depth was able to move about 900 metres and will be deployed soon at 5,500 metres.
    • Weather conditions and the availability of ships also play a role.
    • More tests are being conducted to understand how to bring the nodules up to the surface. A riser system comprising an umbilical cable or electromechanical cable and a hose is being developed.

    What will be the environmental impact?

    • According to the IUCN, these deep remote locations can be home to unique species that have adapted themselves to conditions such as poor oxygen and sunlight, high pressure and extremely low temperatures.
    • Such mining expeditions can make them go extinct even before they are known to science.
    • The deep sea’s biodiversity and ecology remain poorly understood, making it difficult to assess the environmental impact and frame adequate guidelines.
    • Though strict guidelines have been framed, they are only exploration guidelines. A new set of exploitation guidelines are being worked out and discussions are on with the ISA.
    • Environmentalists are also worried about the sediment plumes that will be generated as the suspended particles can rise to the surface harming the filter feeders in the upper ocean layers.
    • Additional concerns have been raised about the noise and light pollution from the mining vehicles and oil spills from the operating vessels.

    Is deep-sea mining economically viable?

    • The latest estimate from the ISA says it will be commercially viable only if about three million tonnes are mined per year.
    • More studies are being carried out to understand how the technology can be scaled up and used efficiently.