ROTHERA RESEARCH STATION, ANTARCTICA – A Calgary researcher who has spent the last eight months in Antarctica studying sea ice says he has seen firsthand the major impact climate change has had on the region.
Vishnu Nandan, a postdoctoral researcher at the University of Calgary, along with Robbie Mallett of the University of Manitoba, have been studying ways that radar satellites can better measure the thickness of Antarctic sea ice and snow.
The research is part of a UK-based project called DEFIANT – Drivers and Effects of Fluctuations in sea Ice in the ANTarctic – which aims to deploy a state-of-the-art ground-based radar system that mimics the satellites in space.
“We actually came in knowing we wouldn’t have a lot of sea ice because it was very warm,” Nandan said in a telephone interview from the Rothera Research Station on Adelaide Island, nearly 1,900 kilometers south of the Falkland Islands.
“We got to where we had the lowest sea ice ever in the last few decades, so we didn’t have a lot of sea ice and only very thin ice in the winter.”
Nandan said the problem is that so much snow falls in the area, sometimes up to a meter, that it is difficult to get accurate satellite measurements of snow and sea ice thickness.
They collected data from the ground-based radar system to account for errors and correct satellite algorithms to produce accurate measurements critical to climate change predictions.
Nandan conducted similar research in the central Arctic Ocean several years ago when he spent a year on an icebreaker studying global warming in detail from a vantage point near the North Pole.
“Arctic sea ice has declined significantly over the last 30 to 40 years – about 70 percent. In comparison, Antarctica has been stable, but in recent years, since around 2016, we have seen a dramatic decline in sea ice in many regions of Antarctica,” Nandan said.
“It’s serious at the moment. It is very bad. If you look at the total area of sea ice, the area is almost a million square kilometers smaller than the previous lowest value in 1986.”
Although there was still a lot of snow, it rained for several days, which was unusual, Nandan said. He added that the warm wind prevents the sea ice from freezing solid.
He said his research, which is also supported by the University of Manitoba, is important considering what could happen with the loss of sea ice.
“Sea ice is white in color and reflects most of the sunlight that hits it,” he said. “If there isn’t enough sea ice, that means there’s a lot of open sea that actually absorbs most of the sunlight.”
Nandan, in turn, said that this would make the polar seas warmer, which could affect both the ecosystem and the weather.
“There are more climate disasters such as tornadoes, hurricanes and extreme weather events such as cloudbursts,” he said.
“It impacts the ecosystem … from alligators and microplankton to animals like seals that require sea ice as habitat.”
Nandan has completed his stay in Antarctica and will return to Calgary next month.