Rapid Arctic sea ice decline to increase rain events across south Asia: Study
New Delhi: A rapid and significant decline in Arctic sea ice will lead to an increase in intense precipitation events (IPEs) across south Asia, exposing people to disasters associated with extreme rain, a recent research paper published in IOP Science said.
Climate scientists from the Indian Institute of Tropical Meteorology, the ministry of earth sciences, and others investigated the tropical rainfall response to the declining Arctic sea ice using observations and climate model simulations.
The Arctic sea ice decline has been accelerating with climate change, the research paper published on May 6 said.
The paper suggested that intense rain events, like those recorded during the 2018 floods in Kerala or the 2013 floods in Uttarakhand, will increase in frequency. Both of these events were intense precipitation events. Rainfall events that exceed a threshold of 150 mm day−1 (in a grid point) are counted as extreme rainfall events.
Scientists found an increase in IPEs, especially during the last two decades. Periods with higher IPEs are associated with a decline in June-July-August Arctic sea ice. The larger increase in IPEs in recent decades often co-occurs with larger Arctic sea ice loss, the paper said.
Also Read: IITM launches joint research projects to revolutionise climate predictions using AI
'Observational evidence and idealised model experiments, in which the Arctic becomes seasonally ice free under greenhouse warming, reveal association between the Arctic sea-ice decline and intense precipitation events (IPEs) over South Asia,' the paper said.
The enhanced Arctic sea ice melt increases mid-latitude waviness and intensifies the circumglobal teleconnection (CGT)-like pattern, while also strengthening the subtropical high over East Asia. This, together with a La Niña-like response in the Pacific, enhances mean summer monsoon rainfall over South Asia.
'The enhanced energy in the tropics and the anomalous mid-latitude intrusions due to the Arctic sea-ice melt provide a conducive environment for moisture convergence and intense summer monsoon precipitation events over South Asia. Our findings reveal that, in a future warming scenario, Arctic sea-ice melt is likely a contributing factor for the amplified mean and IPEs over the South Asian region,' it said.
The June–July–August sea ice concentration in the Arctic is projected to decline under future warming scenarios. The intergovernmental panel on Climate Change's Sixth Assessment Report estimates that Arctic September sea ice may vanish by the mid-21st century.
A sharp decline in the Arctic sea ice anomaly is evident in most emission scenarios, particularly from the mid-century onward. 'Given the observed link between Arctic sea-ice decline and South Asian IPEs, the potential impacts of projected sea-ice loss on IPEs were analysed...we assessed changes in IPE intensity for various global warming levels, calculated relative to the 1850–1900 baseline,' the paper said.
Also Read: No immediate relief in sight from climate crisis
'In summary, Arctic sea ice decline weakens the upper atmospheric circulation and alters energetics, providing a favourable environment for moisture convergence and intense monsoon precipitation. As Arctic warming accelerates under greenhouse gases (GHG), extreme precipitation events over South Asia are projected to increase,' the paper said.
Percentage increase in the intensity of intense precipitation events is much higher over the South Asian region as compared to global IPE.
'For 1-degree warming level, global IPE intensity increases by about 7%, while IPE intensity over South Asian region increases by approximately 20%. Similarly higher increase in the IPEs over the South Asian region as compared to global can be seen with increasing warming level,' the paper said.
Also Read:Climate crisis posing grave health, survival threats: Report
HT reported on June 25 last year that India's summer monsoon is undergoing significant changes, influencing not just agriculture—for which the rains are a lifeblood—but also the length and intensity of the summer.
Arctic sea ice reaches its minimum extent each September. September Arctic sea ice is now shrinking at a rate of 12.2% per decade compared to its average extent during the period from 1981 to 2010, according to the National Aeronautics and Space Administration.
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
NDTV
10 hours ago
- NDTV
Are We Alone? Breakthrough Study Reveals New Way To Find Alien Life
A team of scientists, led by astrophysicist Daniel Apai from the University of Arizona, has developed a novel framework to assess the habitability of exoplanets-planets orbiting stars beyond our solar system. Traditionally, the search for extraterrestrial life has focused on the presence of water. However, Apai's team introduces a more comprehensive model that considers various factors, including temperature and metabolic viability, to determine if known or hypothetical organisms could survive on distant worlds. This new approach, detailed in their recent publication, emphasizes evaluating specific environmental conditions of exoplanets to assess their potential to support life. By moving beyond the simplistic criteria of water presence, the model aims to provide a more accurate assessment of a planet's habitability. According to The Metro, Apai's work is part of the broader "Alien Earths" project, funded by NASA's Astrobiology Program. This interdisciplinary initiative seeks to identify and characterize potentially habitable planets around nearby stars, guiding future missions in the search for life beyond Earth. He wrote in The Conversation. "Even on Earth, organisms require different conditions to survive - there are no camels in Antarctica. By talking about specific organisms, we made the question easier to answer." "Second, the quantitative habitability framework does not insist on black-or-white answers. It compares computer models to calculate a probabilistic answer. Instead of assuming that liquid water is a key limiting factor, we compare our understanding of the conditions an organism requires (the "organism model") with our understanding of the conditions present in the environment (the "habitat model")." Apai's team developed a model to assess habitability by evaluating an organism's needs beyond water. For example, camels require hot, dry climates, so the model correctly rates icy Antarctica as unsuitable. Testing the model on TRAPPIST-1e-like exoplanets, they assessed methanogens-ancient microbes-and found a 69% habitat suitability. This indicates such planets may support simple life forms and are strong candidates for further study.
India Today
11 hours ago
- India Today
Global warming: Why India's slower heating rate could be a ticking climate bomb
When we talk about global warming and the resulting changes in weather patterns, could a slower rise in the Earth's temperature actually be a cause for concern? Surprisingly, while many parts of the world are experiencing unpredictable increases in surface temperature, the South Asian landmass, particularly the Indian subcontinent, is warming at a slower rate. At first glance, this might seem like good news for the residents of this region. However, the reasons behind this slower warming are in fact more worrying for our part of the India has warmed less compared to other regions?advertisementData shows that South Asia's rate of warming over the past few decades is slower than the global average. The region's temperature has risen by approximately 0.09C per decade over the last 40 years, which is significantly lower than the global average of 0.30C per decade, and below the 0.23C recorded for regions at similar latitudes. Considering this area has one of the highest population densities globally and has seen significant reductions in green cover, which normally buffers warming, the slower rise in temperature seems unusual. Therefore, understanding the causes behind this phenomenon in India and neighbouring areas is causing slower warming in South Asia, including IndiaIt is beyond doubt that India, especially the Indo-Gangetic Plain, stretching from Punjab and Haryana to Bangladesh, is among the most polluted regions globally. advertisementWhen discussing global warming, greenhouse gases (GHGs) such as carbon dioxide come to mind, with atmospheric lifetimes ranging from centuries to millennia. Global efforts have led to significant reductions in GHG emissions. Anumita Roychoudhury, Executive Director of the Centre for Science and Environment (CSE), explains, 'The sources of aerosols and greenhouse gases are the same. While Western countries and others have aggressively reduced both, aerosol levels have not fallen similarly in South Asian countries like India, Pakistan, and Bangladesh. Here, pollution from coal-fired power generation and industry remains high.'How aerosols like sulfates mask warming in India?South Asia's temperature trends, as well as the 2024 Berkeley Earth heat map showing global temperature anomalies, highlight the role of cooling aerosols such as sulfates in masking warming. Aerosol pollutants include particulate matter like PM10 and PM2.5, which pose health risks and are subject to various government reduction policies. Beyond particulates, aerosols comprise sulfates, nitrates, fluorinated gases, and methane in the atmosphere. Sulfates, a major aerosol component, have a reflective power akin to a mirror—they scatter sunlight in the upper atmosphere, thereby reducing warming at the Earth's surface. This 'masking effect' means sulfates reflect sunlight and increase cloud reflectivity, effectively hiding the full extent of greenhouse gas-induced temperature and other aerosols' masking effectThe 2024 heat map shows South Asia's temperature anomaly at 1-2C above the 1951-1980 baseline, less severe than anomalies of 4-6C in the Arctic or 2-4C in northern not only scatter incoming solar radiation back into space, reducing sunlight reaching the surface, but also serve as condensation nuclei, increasing cloud droplet numbers and making clouds brighter and more reflective. The South Asian region, including northern India, Pakistan, and Bangladesh, is a global hotspot for air pollution, with sulfate levels often exceeding 20 g/m annually in cities such as Delhi. Sulfates are not the sole aerosols masking temperatures: organic carbon (OC) from biomass burning (e.g., wildfires, agricultural fires) and fossil fuel combustion, often called brown carbon, also scatters sunlight and cools the atmosphere. Similarly, oxides of nitrogen, sea salts, and mineral salts contribute to sunlight scattering, helping keep the Earth India face delayed global warming and more extreme events?Following global policies, South Asia is also reducing sulfate emissions through initiatives like India's clean air programmes. However, as the masking effect weakens over coming decades, the full impact of long-lived GHGs will become apparent. advertisementRecent projections suggest that by 2050, under a moderate emissions scenario (SSP2-4.5), South Asia could experience warming of 1.5-2C above pre-industrial levels, primarily driven by CO and oxides of nitrogen. While methane reductions (e.g., via improved waste management) may slow near-term warming, the long atmospheric lifetime of carbon dioxide means its effects will persist for centuries, heightening risks such as heat stress, with wet-bulb temperatures nearing 35C, and flooding, as seen recently in several Indian InMust Watch
Indian Express
13 hours ago
- Indian Express
Knowledge Nugget: India's First Polar Research Vehicle – A must-know for UPSC
Take a look at the essential concepts, terms, quotes, or phenomena every day and brush up your knowledge. Here's your knowledge nugget for today. (Relevance: Arctic sea ice has been shrinking for decades. Several expeditions have been sent to study the impact of climate change in this region. In 2018, a Mains question was asked on India's interest in the Arctic region. Prelims question was asked on the Arctic Council. In this regard, India's signing of the MoU for the building of the first-ever polar research vehicle is an important development for your UPSC exam.) On June 3rd, Kolkata-based Garden Reach Shipbuilders and Engineers Limited (GRSE), a Government of India undertaking, signed an MoU with Norwegian firm Kongsberg to co-design and build India's first-ever polar research vehicle (PRV) indigenously. GRSE, which has built warships, survey and research vessels, will build the PRV in its yard in Kolkata. 1. The MoU was signed in Oslo in the presence of Union Minister of Ports, Shipping and Waterways Sarbananda Sonowal, who termed it 'a commitment to fostering scientific discovery, advancing India's capabilities in polar and ocean research, and contributing to global efforts to address pressing challenges like climate change.' 2. A PRV is a ship that serves as a platform for research in the polar regions (areas surrounding the North and South Poles). It can also help scientists undertake research in the ocean realm. The PRV will be equipped with the latest scientific equipment, enabling researchers to explore the oceans' depths and study marine ecosystems. 3. India currently operates three research base stations in the polar regions — Bharati and Maitri in Antarctica, and Himadri in the Arctic region — and had been planning to have its own PRV for a while now. 4. The National Centre for Polar and Ocean Research (NCPOR), operating under the Ministry of Earth Sciences, is the nodal agency responsible for the planning and execution of research expeditions to the Arctic, the Antarctic and the Himalayas. 5. The polar regions, the Arctic and Antarctica, offer pristine environments for scientists to study a range of natural phenomena for atmospheric, oceanic, biological, geological, glaciological and earth sciences research. In recent years, climate change research has been attracting scientists to the Arctic region. 6. Arctic sea ice has been shrinking for decades. In the last 40 years, the sea ice extent has been decreasing by 12.6% each decade, according to a 2023 report in the MIT Climate Portal. Expeditions have been sent to study lightning over the Arctic in winter, the role of precipitation in climate change, the characterisation of radio frequency environment, and the role of aerosols on climate change. In this regard, the decision to build the first-ever polar research vehicle is an important development. Research base stations of India 1. India signed the Svalbard Treaty in Paris in 1920. According to the website of arcticportal, 'The treaty establishes Norway's full and undivided sovereignty over Svalbard. Svalbard is part of the Kingdom of Norway, and it is Norway that ratifies and enforces the legislation that is to apply to the archipelago.' 2. It was not until 2007 that the first Indian expedition comprising five scientists visited the International Arctic Research Facilities at Ny-Ålesund with the purpose of initiating studies in Arctic microbiology, atmospheric sciences, and geology. India's permanent research station, Himadri, began operations in July 2008. 3. Dakshin Gangotri in Antarctica was set up in 1983, two years after India's first expedition there. Dakshin Gangotri is now submerged under ice, but India's two other stations, Maitri and Bharti, are in use. It is governed by the Antarctic Treaty. 4. The Antarctic Treaty was originally signed by 12 countries — Argentina, Australia, Chile, France, New Zealand, Norway, the United Kingdom, the United States, the Soviet Union, Belgium, Japan, and South Africa — on December 1, 1959 to provide a framework for peaceful coexistence and scientific cooperation in the continent. 5. Currently, 56 countries are part of the treaty — 29 of which, including all 12 original signatories, are 'Consultative Parties', which are part of the decision-making process. India, which joined the treaty in 1983, is also a Consultative Party. 1. India is making bold moves in shipbuilding. The 2025 Union budget laid the foundation for a maritime resurgence, with mega clusters, a Rs 25,000-crore Maritime Development Fund (MDF), customs duty exemptions, and infrastructure status for large vessels. 2. The Rs 25,000 crore maritime development fund will be for distributed support and promoting competition. The government will contribute 49 per cent of the fund, with the remainder to be mobilised from ports and the private sector. 3. India is increasingly investing in shipbuilding clusters, as India's outward remittance on transport services is increasing with rising exports. In 2022, traders remitted over $109 billion as transport service charges. 4. MDF will facilitate the financing for ship acquisition with the aim of boosting the Indian flagged ships' share in the global cargo volume up to 20% by 2047. By 2030, MDF is aiming at generating upto ₹1.5 lakh crore investment in the shipping sector. 5. The Budget also extended the Shipbuilding Financial Assistance Policy (SBFAP) 2.0 with the total budget outlay of Rs 18,090 crore. It offers direct financial subsidies to Indian shipyards to enhance their competitiveness in the global market. (1) Consider the following statements: 1. India signed the Svalbard Treaty in 1983, leading to India's first research station, Dakshin Gangotri. 2. Himadri is India's permanent research station in Antarctica. Which of the following statements is/are correct? (a) 1 only (b) 2 only (c) Both 1 and 2 (d) None (2) Consider the following countries: (UPSC CSE 2014) 1. Denmark 2. Japan 3. Russian Federation 4. United Kingdom 5. United States of America Which of the above are the members of the 'Arctic Council'? (a) 1, 2 and 3 only (b) 2, 3 and 4 only (c) 1, 4 and 5 only (d) 1, 3 and 5 only Subscribe to our UPSC newsletter. Stay updated with the latest UPSC articles by joining our Telegram channel – IndianExpress UPSC Hub, and follow us on Instagram and X. 🚨 Click Here to read the UPSC Essentials magazine for May 2025. Share your views and suggestions in the comment box or at Khushboo Kumari is a Deputy Copy Editor with The Indian Express. She has done her graduation and post-graduation in History from the University of Delhi. At The Indian Express, she writes for the UPSC section. She holds experience in UPSC-related content development. You can contact her via email: ... Read More
