Fast melting Arctic ice may hit Indian monsoon: Study
The polar Arctic zone, which has been melting for much of the last two centuries, shows an accelerated pace after 1970, a new paper published by scientists at the National Centre for Antarctic and Ocean Research (NCAOR) at Goa this week has said.
The Centre also said that faster melting of Arctic ice can have adverse implications for Indian monsoon rain. The scientists hope that the study will help in further understanding of the global climate and particularly India’s south-west monsoon as they hinge on the rate of melting of polar ice caps.
The research led by Manish Tiwari and Vikash Kumar have reconstructed the warming of the Arctic over the last two centuries — a period encompassing 1810-2010 — by examining the organic productivity from sediment samples from an Arctic fjord known as Kongsfjorden in Svalbard — a remote archipelago in the Arctic Ocean near the north pole.
“We noticed that there has been an increase in glacial melting driven by warming over the past two centuries. The Arctic witnessed a persistently increasing warming during the studied period with a particularly accelerated tone post-1970s,” Tiwari said, adding that climate change in polar regions is taking place at twice the global average.
Cascading effects of these changes in the Arctic region are projected to significantly alter the state and the balance of the earth’s climate system.
To help track past changes, the scientists studied the sediments for the presence of organic carbon and other signatures of past environmental changes preserved in the sediments deposited on the fjord floor.
Increasing glacial meltwater in the Arctic reduced the availability of light and thus reduced productivity resulting in a lower presence of organic carbon, the study said.
The results revealed that the Arctic has witnessed consistent periods of warming over the last two centuries except for the period around 1840 and 1900, where glacial melting was at its lowest. The Arctic warming has been gradually increasing from 1840 onwards while the trend increased after 1900, particularly accelerating after 1970.
Besides sea level rise, the NCAOR has also found that warming at the poles and glacier melting is affecting India’s weather patterns, in particular, the South West Monsoon.
An earlier study by the NCAOR have found a direct physical link between the warming climate and the monsoon. The increased melting of Arctic glaciers affected the difference between land and sea temperature, resulting in higher intensity of the monsoon rain.