If there’s no sea ice, polar oceans become really warm, affecting other oceans, including the Indian Ocean, though it’s a gradual process
Indo-Canadian researcher Vishnu Nandan stands on the Antarctic sea ice with glacial ice cliffs in the background. (Robbie Mallett/ University of Manitoba)
While the loss of Arctic ice cover has been well known for decades, researchers have now found what is possibly the lowest area covered by sea ice this year in the Antarctic, a phenomenon that could have global ramifications including warmer ocean temperatures. This could even indirectly affect the timing of the annual monsoon in India in the future.
The two researchers currently studying and measuring the thickness of sea ice at the remote Rothera Research Station of the British Antarctic Survey on the continent are Indo-Canadian Dr Vishnu Nandan, who is affiliated with the universities of Calgary and Manitoba, and Dr Robbie Mallett from the University of Manitoba.
The researchers are wintering in Rothera as part of British project ‘DEFIANT’, or Drivers and Effects of Fluctuations in sea Ice in the ANTarctic.
In a telephonic interview with the HT speaking from Antarctica, Nandan, who is originally from Thiruvananthapuram in Kerala, said, “The Arctic sea ice has been declining over the past many decades. The Antarctic sea ice has been stable but has been showing decline since 2016. The lowest area covered by sea ice at the end of winters here was recorded this year.”
The researchers use ground-based radar systems to mimic satellite radars to measure the thickness of sea ice and snow in Antarctica.
“This year’s sea ice extent is almost 1 million sqkm less than in 1986,” Nandan said, based on what scientists across the globe have found. They have attributed multiple factors for this loss, including extreme storm events and warm weather patterns that delay the ocean freeze-up, with a lot of winds preventing the stability of sea ice.
There are global consequences if sea ice and snow loss continue unabated. “Sea ice and snow is white and most of the sunlight reflects off it. The open ocean, however, absorbs the heat. If there’s no sea ice, polar oceans become really warm, affecting other oceans, including the Indian Ocean, though it’s a gradual process,” he explained.
That could lead to disruption in ocean circulation, and a surfeit of ocean heat is a “gradual recipe for climate disaster”, he said, as it could cause extreme weather events like cyclones, and, importantly for countries like India, “unpredictable monsoon timings.”
Plus, sufficient sea ice is necessary for the survival of local flora and fauna such as seals, penguins, algae and phytoplankton.
Nandan is a radar remote sensing specialist who tracks sea ice thickness. The researchers have been at the Antarctic station since March this year and expect to return to Canada in November.