WEDNESDAY, JULY 03, 2024
SHASHWAT GUPTA RAY
PANJIM: Due to the climate change, sea ice concentration (SIC) in the central Arctic Sea is reducing, which is affecting the Indian Summer Monsoon (ISMR).
While reduced SIC decreases rainfall over western and southern peninsular India, it increases precipitation specifically over north-western and central India, finds a latest study done by the National Centre for Polar and Ocean Research (NCPOR), Goa.
The study has also revealed that increased sea ice concentrations (SIC) in the Hudson Bay, Gulf of Lawrence, and Seas of Okhotsk are associated with reduced rainfall in central and north-western India. This phenomenon is attributed to the influence of increased sea ice on atmospheric pressure systems and wind patterns.
“The reduced SIC influences pressure patterns and wind forcing, with effects persisting into summer. SIC in these areas can cause alterations in the North Atlantic Oscillation (NAO) pattern, which subsequently affect the positioning of the monsoon trough and the strength of the monsoon winds. The enhanced sea ice alters the heat flux and atmospheric circulation, reinforcing high-pressure systems that can suppress monsoon activity over central and northwest India,” Scientist E, NCPOR and corresponding author of the study, Avinash Kumar told O Heraldo.
The findings of the study, done with collaboration with Korea Polar Research Institute, Incheon, South Korea, have significant implications in collaboration with the Korea Polar Research Institute, Incheon, South Korea, have significant implications for understanding and predicting Indian Summer Monsoon Rainfall in relation to Arctic sea ice. The rainfall variation and intensity have a significant impact on India in terms of water availability and agricultural production.
“The study found that the reduction of sea ice in the central Arctic region leads to increased rainfall in central and north-eastern India, while low sea ice in the Barents-Kara Sea delays the onset and intensity of the Indian monsoon season. In the western and southern peninsular regions, decreased Arctic sea ice concentration (SIC) is linked to reduced rainfall, potentially leading to water shortages and negatively impacting agriculture. The reduction in monsoon rains could result in agricultural deficits, threatening food security and necessitating reliance on irrigation and alternative water sources,” Juhi Yadav, Project Scientist, NCPOR and lead author, said.
“Conversely, central and northern India may experience increased precipitation, which could enhance water availability and boost agricultural productivity. However, the surplus rainfall might also lead to challenges such as flooding, which can damage crops and infrastructure. Additionally, the study indicates that variations in Arctic SIC can contribute to extreme rainfall events in certain parts of India, exacerbating both drought and flood risks,” Rahul Mohan, Group Director of Polar Sciences, NCPOR, said.
Overall, the findings suggest a complex interplay between Arctic SIC and Indian monsoon patterns, highlighting the need for adaptive water management and agricultural practices to address the varying impacts across different regions of India.
Speaking about the implications for Goa, which is also situated on the west coast, Kumar said, “Goa, located on the western peninsula of India, could experience significant impacts due to the relationship between Arctic SIC and the Indian summer monsoon rainfall.”
“The study suggests that decreased sea ice concentration in the Central Arctic is linked to reduced rainfall in the western peninsular region, which includes Goa. This reduction in rainfall could lead to water scarcity, affecting agriculture, water supply, and overall ecosystem health in the region,” Kumar said.
To mitigate the adverse effects of changing Arctic sea ice on the Indian monsoon, several measures can be implemented. Efficient water management practices, including rainwater harvesting and improved irrigation, are essential during periods of reduced rainfall. Scientist NCPOR, Rohit Srivastava said.
“Agricultural strategies like promoting drought-resistant crops and adjusting planting schedules can adapt to shifting rainfall patterns. Developing climate-resilient infrastructure, integrating climate projections into policy-making, raising public awareness on climate change, and investing in research to understand connections between Arctic sea ice and the monsoon are crucial steps towards building resilience,” M Ravichandran, Secretary to Government of India, Ministry of Earth Sciences, said.
The study titled ‘Contrasting response of regional spring Arctic Sea ice variations on Indian summer monsoon rainfall’ has been published in the Remote Sensing of Environment journal.
