Date: 23/08/2022

Relevance: GS-3: Conservation, environmental pollution and degradation, environmental impact assessment Disaster and disaster management.

Key Phrases: Arctic amplification, Ice-Albedo Feedback, Lapse Rate Feedback, Water Vapour Feedback, Ocean Heat Transport, Melting of Greenland Ice, Svalbard Treaty, Arctic Council

Why in News?

• The Finnish Meteorological Institute researchers have published their study in the Communications Earth & Environment journal, concluding that the Arctic is heating four times faster than the rest of the planet.

Key Highlights

• The warming is more concentrated in the Eurasian part of the Arctic, where the Barents Sea north of Russia and Norway is warming at an alarming rate which is seven times faster than the global average.
• The region is fast changing and even the best climate models may not be able to capture the rate of change and predict it accurately.

What is Arctic amplification?

• The phenomenon of global warming i.e., the long-term heating of the earth’s surface, has been expedited due to anthropogenic forces or human activities since pre-industrial times and has increased the planet’s average temperature by 1.1 degrees Celsius.
• The changes are witnessed across the whole planet but any change in the surface air temperature and the net radiation balance tends to produce larger changes at the north and south poles.
• This phenomenon is known as polar amplification.
• These changes are more pronounced at the northern latitudes and are known as Arctic amplification.

What are the reasons for arctic amplification?

• The primary cause among the many global warming-driven causes for this amplification include ice-albedo feedback, lapse rate feedback, water vapour feedback, and ocean heat transport.
• Sea ice and snow have high albedo (a measure of the reflectivity of the surface), implying that they are capable of reflecting most of the solar radiation as opposed to water and land.
• Global warming is resulting in diminishing sea ice.
• As the sea ice melts, the Arctic Ocean is absorbing more solar radiation, thereby driving the amplification.
• The lapse rate or the rate at which the temperature drops with elevation decreases with warming.
• Studies show that the ice-albedo feedback and the lapse rate feedback are responsible for 40% and 15% of polar amplification respectively.

What do the previous studies say?

• The Inter-governmental Panel on Climate Change released a ‘Special Report on the Ocean and Cryosphere in a Changing Climate’ in 2019, which said that the “Arctic surface air temperature has likely increased by more than double the global average over the last two decades.”
• In May 2021, the Arctic Monitoring and Assessment Programme (AMAP) warned that the Arctic has warmed three times quicker than the planet, and the chance of the sea ice completely disappearing in summers is 10 times greater, if the planet is warmer by two degree Celsius above the pre-industrial levels.
• The report also said that the average annual temperature in the region increased by 3.1 degree Celsius compared to the 1 degree Celsius for the planet.
• However, recent studies have shown that the mean Arctic amplification saw steep changes in 1986 and 1999, when the ratio reached 4.0, implying four times faster heating than the rest of the planet.

What are the consequences of Arctic warming?

1. Melting of Greenland ice:
   • The Greenland ice sheet is melting at an alarming rate while the rate of accumulation of sea ice has been remarkably low since 2000, marked by young and thinner ice replacing the old and thicker ice sheets.
   • The Greenland ice sheet saw a sharp spike in the rate and extent of melting between July 15-17 this year.
   • The unusual summer temperatures resulted in a melt of 6 billion tonnes of ice sheet per day, amounting to a total of 18 billion tonnes in a span of three days, enough to cover West Virginia in a foot of water.
2. Rise in sea level:
   • Greenlandic ice sheet holds the second largest amount of ice, after Antarctica, and therefore it is crucial for maintaining the sea level.
   • If the sheet melts completely, the sea level would rise by seven metres, capable of subsuming island countries and major coastal cities.
3. Impact on biodiversity:
   • The warming of the Arctic Ocean and the seas in the region, the acidification of water, and changes in the salinity levels are impacting the biodiversity, including the marine species and the dependent species.
   • The warming is also increasing the incidence of rainfall which is affecting the availability and accessibility of lichens to the reindeer.
   • The Arctic amplification is causing widespread starvation and death among the Arctic fauna.
4. Thawing of permafrost:
   • The permafrost in the Arctic is thawing and in turn releasing carbon and methane which are among the major greenhouse gases responsible for global warming.
   • The thawing and the melting will also release the long-dormant bacteria and viruses that were trapped in the permafrost and can potentially give rise to diseases.
   • The best-known example of this is the permafrost thaw leading to an anthrax outbreak in Siberia in 2016, where nearly 2,00,000 reindeer died.

What is the impact on India?

• The link between the changing Arctic and the monsoons in the subcontinent is growing in importance due to the extreme weather events the country faces, and the heavy reliance on rainfall for water and food security.
• A study titled ‘A possible relation between Arctic sea ice and late season Indian Summer Monsoon Rainfall extremes’ published in 2021 by a group of Indian and Norwegian scientists found that the reduced sea ice in the Barents-Kara sea region can lead to extreme rainfall events in the latter half of the monsoons in September and October.
• The changes in the atmospheric circulation due to diminishing sea ice combined with the warm temperatures in the Arabian Sea contribute to enhanced moisture and drive extreme rainfall events.
• In 2014, India deployed IndARC, India’s first moored-underwater observatory in the Kongsfjorden fjord, Svalbard, to monitor the impact of the changes in the Arctic Ocean on tropical processes such as the monsoons.
• According to the World Meteorological Organization’s report, ‘State of Global Climate in 2021’, the sea level along the Indian coast is rising faster than the global average rate.
• One of the primary reasons for this rise is the melting of sea ice in the polar regions, especially the Arctic.
• The Arctic amplification furthers the idea that “what happens in the Arctic does not remain in the Arctic” and can substantially affect tropical processes far south.

Source: The Hindu

Mains Question:

Q. Discuss the phenomenon and causes of arctic amplification. Examine its consequences worldwide as well as its impact on India. (250 words).