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GS Paper: GS1-14.Important Geophysical phenomena such as earthquakes, Tsunami, Volcanic activity, cyclone etc.,

  • Thawing Permafrost

    The latest IPCC report has warned that increasing global warming will result in reductions in Arctic permafrost and the thawing of the ground is expected to release greenhouse gases like methane and carbon dioxide.

    What is Permafrost?

    • ‘Permafrost’ or permanently frozen ground is land that has been frozen at or below 0 degrees Celsius for two or more consecutive years.
    • A staggering 17 per cent of Earth’s entire exposed land surface is comprised of permafrost.
    • Composed of rock, sediments, dead plant and animal matter, soil, and varying degrees of ice, permafrost is mainly found near the poles, covering parts of Greenland, Alaska, Northern Canada, Siberia and Scandinavia.
    • The Arctic region is a vast ocean, covered by thick ice on the surface (called sea ice), surrounded by land masses that are also covered with snow and ice.

    Permafrost thawing

    • When permafrost thaws, water from the melted ice makes its way to the caves along with ground sediments, and deposits on the rocks.
    • In other words, when permafrost thaws, the rocks grow and when permafrost is stable and frozen, they do not grow.

    Why thawing?

    • The link between the Siberian permafrost and Arctic sea ice can be explained by two factors:
    • One is heat transport from the open Arctic Ocean into Siberia, making the Siberian climate warmer.
    • The second is moisture transport from open seawater into Siberia, leading to thicker snow cover that insulates the ground from cold winter air, contributing to its warming.
    • This is drastically different from the situation just a couple of decades ago when the sea ice acted as a protective layer, maintaining cold temperatures in the region and shielding the permafrost from the moisture from the ocean.
    • If sea ice (in the summer) is gone, permafrost start thawing.

    Impact on Climate Change

    • Due to relentlessly rising temperatures in the region, since the late-twentieth century, the Arctic sea ice and surrounding land ice are melting at accelerating rates.
    • When permafrost thaws due to rising temperatures, the microbes in the soil decompose the dead organic matter (plants and animals) to produce methane (CH4) and carbon dioxide (CO2), both potent greenhouse gases.
    • CH4 is at least 80 times more powerful than CO2 on a decadal timescale and around 25 times more powerful on a century timescale.
    • The greenhouse gases produced from thawing permafrost will further increase temperatures which will, in turn, lead to more permafrost thawing, forming an unstoppable and irreversible self-reinforcing feedback loop.
    • Experts believe this process may have already begun. Giant craters and ponds of water (called ‘thermokarst lakes’) formed due to thawing have been recorded in the Arctic region. Some are so big that they can be seen from space.

    Why a matter of concern?

    • An estimated 1,700 billion tonnes — twice the amount currently present in the atmosphere — of carbon is locked in all of the world’s permafrost.
    • Even if half of that were to be released to the atmosphere, it would be game over for the climate.
    • Scientific estimates suggest that the Arctic Ocean could be largely sea ice-free in the summer months by as early as 2030, based on observational trends, or as late as 2050, based on climate model projections.

    Potential to cause another pandemic

    Ans. Permafrost has many secrets.

    • When the permafrost was formed thousands of years ago, there weren’t many humans who lived in that region which was necessarily very cold.
    • Researchers recently found mammoths in the permafrost in Russia.
    • And some of these mammoth carcasses when they begin to degrade again may reveal bacteria that were frozen thousands of years ago.
    • So there will be surprises. But whether they will be lethal surprises is just not possible to say.

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  • Climate Action and Finance Mobilization Dialogue (CAFMD)

    India and the US has together launched the “Climate Action and Finance Mobilization Dialogue (CAFMD)”.

    What is CAFMD?

    • The CAFMD is one of the two tracks of the India-U.S. Climate and Clean Energy Agenda 2030 partnership launched at the Leaders’ Summit on Climate in April 2021, by PM Modi and US President Mr. Biden.
    • The dialogue will strengthen India-US bilateral cooperation on climate and environment.
    • It will also help to demonstrate how the world can align swift climate action with inclusive and resilient economic development, taking into account national circumstances and sustainable development priorities.

    Key agendas

    • The US will collaborate with India to work towards installing 450 GW of renewable energy by 2030.
    • Currently, India’s installed power capacity is projected to be 476 GW by 2021-22 and is expected to rise to at least 817 GW by 2030.

    CAFMD would have three pillars:

    1. Climate Action Pillar: which would have joint proposals looking at ways in emissions could be reduced in the next decade.
    2. Setting out a Roadmap: to achieving the 450GW in transportation, buildings and industry.
    3. Finance Pillar: would involve collaborating on attracting finance to deploy 450 GW of renewable energy and demonstrate at scale clean energy technologies.

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  • Places in news: Qeqertaq Avannarleq Island

    A group of researchers who went out to collect samples off the coast of Greenland in July found themselves on a tiny, uninhabited and previously unknown island.

    Qeqertaq Avannarleq

    • Measuring 60×30 metres and with a peak of three metres above sea level, it has now become the new northernmost piece of land on Earth.
    • Before this, Oodaaq was marked as the Earth’s northernmost terrain.
    • The new island is made up of seabed mud and moraine, i.e. soil, rock and other material left behind by moving glaciers, and has no vegetation.
    • The group has suggested the discovery be named ‘Qeqertaq Avannarleq’, which is Greenlandic for “the northernmost island”.

    How this island came to existence?

    Ans. Undoubtedly, climate change in Greenland

    • Global warming has had a severe effect on the ice sheet of Greenland.
    • The new island, which was exposed by shifting pack ice, is, however, not a direct consequence of climate change.

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  • Mumbai Climate Action Plan (MCAP)

    The Brihanmumbai Municipal Corporation (BMC) is drafting a Mumbai Climate Action Plan (MCAP) in a bid to tackle climate challenges.

    What is the Mumbai Climate Action Plan?

    • Amid warnings of climate change leading to extreme weather events in the city, the civic body has started preparing the Mumbai Climate Action Plan (MCAP).
    • It will look at climate resilience with mitigation and adaptation strategies by focusing on six areas —
    1. Sustainable waste management
    2. Urban greening and Biodiversity
    3. Urban flooding and Water Resource Management
    4. Building Energy Efficiency
    5. Air Quality and
    6. Sustainable Mobility
    • The plan is expected to be ready by November ahead of the United Nations Climate Change (COP26) conference at Glasgow, Scotland.

    Why does Mumbai need a climate action plan?

    Mumbai’s climate action plan will help set a vision and implement strategies to fight these climate challenges with mitigation and adaptation steps.

    • Flash floods: As per a study conducted by the World Resource Institute (WRI) India, the city will face two major climate challenges — the rise in temperature, and extreme rain events which will lead to flooding.
    • Temperature rise: The city has seen a constant rise in temperature after 2007, and a substantial increase in intense rainfall and storm events in the last five years.
    • Sea level rise: A recent report from the IPCC has warned that at least 12 Indian coastal cities including Mumbai will face a sea rise of 0.1 metres to 0.3 metres in the next three decades due to climate change.

    What is the greenhouse gas emission of the city?

    • The data show that Mumbai’s greenhouse gas emission was 34.3 million tonnes in 2019, and of which 24.23 million tonnes or 71 per cent came from the energy sector which is mainly based on coal.
    • At least 24 per cent or 82,21,902 tonnes is from transport, and the remaining 5 per cent or 18,53,741 tonnes from solid waste management.
    • The maximum contribution from the energy sector was mainly due to domestic and commercial usage of electricity.
    • As per the data, 95 percent of Mumbai’s electricity is coal-based and needs to be shifted to renewable energy to bring down emissions.

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  • Melting of the Greenland’s Snow Cover

    Recently the summit of Greenland received rain and not snow. This has sparked fear as scientists are pointing to it as evidence that Greenland is warming rapidly.

    About Greenland

    • Greenland is the world’s largest island located between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago.
    • It is an autonomous territory within the Kingdom of Denmark.
    • Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe (specifically Norway and Denmark, the colonial powers).
    • The majority of its residents are Inuit, whose ancestors migrated from Alaska through Northern Canada, gradually settling across the island by the 13th century.
    • It has three-quarters of its surface covered with a permanent ice sheet, which is increasingly coming under threat because of climate change.

    Rain at Greenland: The rarest phenomenon

    • At the highest point on Greenland’s ice sheet, the US maintains a Summit Station, a research facility that observes changes occurring over the island as well as in Arctic weather.
    • Researchers observed rain at the normally frigid summit, with the precipitation extending up to Greenland’s southeast coast.
    • The rain, coupled with warm conditions, caused a major melting event at the summit.
    • This led to rapid ice melting running off into the ocean in volumes, thus accelerating global sea-level rise.

    A cause of worry

    • Greenland, which is two-thirds the size of India, already witnessed one of its most severe melting events.
    • It has lost 8.5 billion tons of surface mass in one day– the third such extreme event in the past decade.
    • The UN’s “code red” climate report released last week concluded that the burning of fossil fuels led to Greenland melting in the last 20 years.
    • The rapid melting is also threatening polar bears, which now have to make their way hundreds of kilometers towards Greenland’s interior from the coasts, where they usually find enough food.

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  • Atlantic Meridional Overturning Circulation (AMOC)

    According to the IPCC’s Report (AR6), the Atlantic Meridional Overturning Circulation (AMOC), is losing its stability.

    What is AMOC?

    • 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.
    • Gulf Stream, a part of the AMOC, is a warm current responsible for mild climate at the Eastern coast of North America as well as Europe.

    What happens if AMOC collapses?

    • Colder Europe: Without a proper AMOC and Gulf Stream, Europe will be very cold.
    • Rainfall decline: Modelling studies have shown that an AMOC shutdown would cool the northern hemisphere and decrease rainfall over Europe.
    • El-Nino trigger: It can also have an effect on the El Nino.
    • Cooling of Atlantic: AMOC collapse could bring about large, markedly different climate responses: a prominent cooling over the northern North Atlantic and neighboring areas.
    • Weaker thermohaline: 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.

    Has the AMOC weakened before?

    • AMOC and THC strength has always been fluctuating, mainly if you look at the late Pleistocene time period (last 1 million years).
    • The extreme glacial stages have seen weaker circulation and slowdown in AMOC, while the glacial terminations have shown a stronger AMOC and circulation.
    • AMOC has been relatively stable until the late 19th century.
    • With the end of the little ice age in about 1850, the ocean currents began to decline, with a second, more drastic decline following since the mid-20th century.

    Why is the AMOC slowing down?

    • Climate models have long predicted that global warming can cause a weakening of the major ocean systems of the world.
    • Last month researchers noted that a part of the Arctic’s ice called “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.

    Influence of 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.

    Now try this:

    Q.With reference to Ocean Mean Temperature (OMT), which of the following statements is/are correct? (CSP 2020)

    1. OMT is measured up to a depth of 26ºC isotherm which is 129 meters in the south-western Indian Ocean during January-March.
    2. OMT collected during January-March can be used in assessing whether the amount of rainfall in monsoon will be less or more than a certain long-term mean.

    Select the correct answer using the code given below:

    (a) 1 only

    (b) 2 only

    (c) Both 1 and 2

    (d) Neither 1 nor 2

    [wpdiscuz-feedback id=”t9bjw2xexz” question=”Please leave a feedback on this” opened=”1″]Post your answers here:[/wpdiscuz-feedback]

    Back2Basics:  Ocean Currents

  • IPCC’s Climate Assessment Report

    The Geneva-based Intergovernmental Panel on Climate Change (IPCC) will release the first part of its Sixth Assessment Report, the periodic status check that has now become the most widely accepted scientific view of the state of the Earth’s climate.

    What is IPCC?

    • The IPCC, an intergovernmental body was established in 1988 by the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP).
    • It was later endorsed by the UN General Assembly. Membership is open to all members of the WMO and UN.
    • The IPCC produces reports that contribute to the work of the UN Framework Convention on Climate Change (UNFCCC), the main international treaty on climate change.
    • The objective of the UNFCCC is to “stabilize greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic (human-induced) interference with the climate system.”
    • The IPCC’s Fifth Assessment Report was a critical scientific input into the UNFCCC’s Paris Agreement in 2015.

    What are IPCC reports?

    • IPCC reports cover the scientific, technical and socioeconomic information relevant to understanding the scientific basis of risk of human-induced climate change, its potential impacts and options for adaptation and mitigation.
    • The IPCC does not carry out original research, nor does it monitor climate or related phenomena itself.
    • Rather, it assesses published literature, including peer-reviewed and non-peer-reviewed sources.
    • However, the IPCC can be said to stimulate research in climate science.

    The Assessment Reports

    • The five previous assessment reports that have come out since the IPCC was established in 1988 have formed the basis of international climate change negotiations, and the actions of the governments.
    • Their value has been globally acknowledged, and the fourth assessment report, which came out in 2007, won the IPCC the Nobel Peace Prize.
    • Each of these voluminous reports, the last couple of them running into thousands of pages, have built upon the previous ones with updated knowledge and understanding of the climate system.
    • The reports have presented projections for temperature rise till 2100 under different scenarios and the kind of impacts that can be expected under each of these pathways.

    Key projections of the 6th Report

    Apart from incorporating the latest available scientific evidence, the Sixth Assessment Report is also attempting to provide more actionable information to help governments take policy decisions.

    • REGIONAL FOCUS: It is expected that this report would likely state what the scenarios for sea-level rise in the Bay of Bengal region is, not just what the average sea-level rise across the world is likely to be.
    • EXTREME EVENTS: There is expected to be bigger focus on extreme weather events, like the ones we have seen in the last few weeks.
    • CITIES: Densely populated mega-cities are supposed to be among the most vulnerable to impacts of climate change. The report is expected to present specific scenarios the climate change impacts on cities and large urban populations, and also implications for key infrastructure.
    • SYNERGIES: IPCC is expected to present a more integrated understanding of the situation, cross-link evidence and discuss trade-offs between different options or pathways, and also likely to cover social implications of climate change action by countries.

    Why it matters?

    • The IPCC assessment reports have been extremely influential in directing the dialogue and action on climate change.
    • The First Assessment Report led to the setting up of the UNFCCC, the umbrella agreement under which international negotiations on climate change take place every year.
    • The Second Assessment Report was the basis for the 1997 Kyoto Protocol that ran till last year, and the Fifth Assessment Report, which came out in 2014, guided the Paris Agreement.
    • The global climate architecture is now governed by the Paris Agreement, which replaced the Kyoto Protocol from this year.
    • There have been enough indications to suggest that global action was far below what was needed to keep the temperatures below 2°C, as mandated under the Paris Agreement.
    • In the immediate future, the IPCC report could serve as the most important warning towards the rapidly closing window of opportunity.

    Try this PYQ now:

    Q.The United Nations Framework Convention on Climate Change (UNFCCC) is an international treaty drawn at:

    (a) United Nations Conference on the Human Environment, Stockholm,1972

    (b) UN Conference on Environment and Development, Rio de Janeiro, 1992

    (c) World Summit on Sustainable Development, Johannesburg, 2002

    (d) UN Climate Change Conference, Copenhagen, 2009

    [wpdiscuz-feedback id=”9729137kxt” question=”Please leave a feedback on this” opened=”1″]Post your answers here: [/wpdiscuz-feedback]

    Back2Basics: UNFCCC

    • The UNFCCC established an international environmental treaty to combat “dangerous human interference with the climate system”, in part by stabilizing greenhouse gas concentrations in the atmosphere.
    • It was signed by 154 states at the UN Conference on Environment and Development (UNCED), informally known as the Earth Summit, held in Rio de Janeiro from 3 to 14 June 1992.

  • Net-Zero Concept in Climate Change

    Independent charitable organization Oxfam has said that ‘net zero’ carbon targets that many countries have announced maybe a “dangerous distraction” from the priority of cutting carbon emissions.

    What does Net-Zero mean?

    • Net-zero, which is also referred to as carbon-neutrality, does not mean that a country would bring down its emissions to zero.
    • That would be gross-zero, which means reaching a state where there are no emissions at all, a scenario hard to comprehend.
    • Therefore, net-zero is a state in which a country’s emissions are compensated by absorption and removal of greenhouse gases from the atmosphere.

    Achieving net-zero targets

    • One way by which carbon can be absorbed is by creating carbon sinks.
    • Until recently, the Amazon rainforests in South America, which are the largest tropical forests in the world, were carbon sinks.
    • But eastern parts of these forests have started emitting CO2 instead of absorbing carbon emissions as a result of significant deforestation.

    What’s the difference between gross zero and net zero?

    • Given the impact that carbon emissions have on our planet, you might wonder why we aren’t aiming for zero, or gross zero, rather than net-zero.
    • Gross zero would mean stopping all emissions, which isn’t realistically attainable across all sectors of our lives and industry. Even with best efforts to reduce them, there will still be some emissions.
    • Net-zero looks at emissions overall, allowing for the removal of any unavoidable emissions, such as those from aviation or manufacturing.
    • Removing greenhouse gases could be via nature, as trees take carbon dioxide from the atmosphere, or through new technology or changing industrial processes.

    What is carbon negativity?

    • It is even possible for a country to have negative emissions if the absorption and removal exceed the actual emissions.
    • Bhutan has negative emissions because it absorbs more than it emits.

    Which countries have recently announced net-zero targets?

    • In 2019, the New Zealand government passed the Zero Carbon Act, which committed the country to zero carbon emissions by 2050 or sooner.
    • In the same year, the UK’s parliament passed legislation requiring the government to reduce the UK’s net emissions of greenhouse gases by 100 per cent relative to 1990 levels by the year 2050.
    • More recently, US announced that the country will cut its greenhouse gas emissions by at least 50 per cent below 2005 levels by 2030.
    • The European Union too, has a similar plan, called “Fit for 55”, the European Commission has asked all of its 27 member countries to cut emissions by 55 per cent below 1990 levels by 2030.
    • Last year, China also announced that it would become net-zero by the year 2060 and that it would not allow its emissions to peak beyond what they are in 2030.

    What does the Oxfam report say?

    • “Land-hungry ‘net zero’ schemes could force an 80 per cent rise in global food prices and more hunger while allowing rich nations and corporates to continue “dirty business-as-usual”.
    • The report says that if the challenge of change is tackled only by way of planting more trees, then about 1.6 billion hectares of new forests would be required to remove the world’s excess carbon by 2050.
    • Currently, countries’ plans to cut emissions will only lead to a one percent reduction by the year 2030.
    • Oxfam estimates that it could rise by 80 percent by the year 2050.

  • [pib] Centre launches Secured Logistics Document Exchange (SLDE) and GHG Calculator

    With an aim to further improve ease of doing business, Centre today launched the “Secured Logistics Document Exchange” along with a Calculator for Green House Gas Emissions.

    Secured Logistics Document Exchange (SLDE)

    • The SLDE platform is a solution to replace the present manual process of generation, exchange and compliance of logistics documents with a digitized, secure and seamless document exchange system.
    • It is set to improve logistics efficiency, reduce logistics cost, and promote multi-modality and sustainability in a big way.
    • This will enable generation, storage and interchange of logistics-related documents digitally using Aadhaar and blockchain-based security protocols for data security and authentication.
    • It will also provide a complete audit trail of document transfer, faster execution of transaction, lower cost of shipping and overall carbon footprint, easy verification of authenticity of documents, lowered risk of fraud, etc.
    • The proof of concept of the platform has been developed and executed with banks (ICICI, Axis Bank, State Bank of India and HDFC Bank) and stakeholders including freight forwarders, exporters, importers and vessel operators.

    Green House Gas (GHG) Emission Calculator

    • The GHG Calculator is an efficient, user-friendly tool and provides for calculating and comparing GHG emissions across different modes.
    • It allows for a commodity-wise comparison of GHG emissions and total cost of transportation, including their environmental cost, between movement by road and rail.
    • The tool is intended to facilitate appropriate modal choice for all concerned.

    Back2Basics: Green House Gases (GHGs)

    • A greenhouse gas (GHG) is a gas that absorbs and emits radiant energy within the thermal infrared range, causing the greenhouse effect.
    • The primary greenhouse gases in Earth’s atmosphere are water vapor (H 2O), carbon dioxide (CO 2), methane (CH 4), nitrous oxide (N 2O), and ozone (O3).
    • Without greenhouse gases, the average temperature of Earth’s surface would be about −18 °C (0 °F), rather than the present average of 15 °C (59 °F).
    • The atmospheres of Venus, Mars, and Titan also contain greenhouse gases.

  • Places in news: Great Barrier Reef

    Chinese official has said that political tensions between Beijing and Australia were not behind a UNESCO recommendation to place the Great Barrier Reef on its endangered list.

    Great Barrier Reef

    • The Great Barrier Reef is the world’s largest coral reef system composed of over 2,900 individual reefs and 900 islands.
    • It is stretched for over 2,300 kilometres over an area of approximately 344,400 square kilometres.
    • The reef is located in the Coral Sea, off the coast of Queensland, Australia.
    • It was world heritage listed in 1981 by UNESCO as the most extensive and spectacular coral reef ecosystem on the planet.

    Importance of Corals

    Coral reefs are some of the most diverse and valuable ecosystems on Earth.

    • They support more species per unit area than any other marine environment, including about 4,000 species of fish, 800 species of hard corals and hundreds of other species.
    • This biodiversity is considered key to finding new medicines for the 21st century.
    • Medical use: Many drugs are now being developed from coral reef animals and plants as possible cures for cancer, arthritis, human bacterial infections, viruses, and other diseases.
    • Fisheries: Healthy coral reefs support commercial and subsistence fisheries as well as jobs and businesses through tourism and recreation.
    • Local economies receive billions of dollars from visitors to reefs through diving tours, recreational fishing trips, hotels, restaurants, and other businesses based near reef ecosystems.
    • Coral reef structures also buffer shorelines against 97 per cent of the energy from waves, storms, and floods, helping to prevent loss of life, property damage, and erosion.

    Answer this PYQ in the comment box:

    Q.Consider the following statements:

    1. Most of the world’s coral reefs are in tropical waters.
    2. More than one-third of the world’s coral reefs are located in the territories of Australia, Indonesia and the Philippines.
    3. Coral reefs host far more number of animal phyla than those hosted by tropical rainforests.

    Which of the above statements is/are correct?

    (a) 1 and 2 only

    (b) 3 only

    (c) 1 and 3 only

    (d) 1 and 3 only

    Back2Basisc: Coral Reef

    • Coral reefs are built by and made up of thousands of tiny animals—coral “polyps”—that are related to anemones and jellyfish.
    • Polyps are shallow-water organisms that have a soft body covered by a calcareous skeleton. The polyps extract calcium salts from seawater to form these hard skeletons.
    • The polyps live in colonies fastened to the rocky seafloor.
    • The tubular skeletons grow upwards and outwards as a cemented calcareous rocky mass collectively called corals.
    • When the coral polyps die, they shed their skeleton on which new polyps grow.
    • The cycle is repeated for millions of years leading to the accumulation of layers of corals shallow rock created by these depositions is called a reef.