A Calgary researcher, who has stayed in Antarctica for the past eight months to study the sea ice, says he has witnessed the effects of climate change in this region of the globe.
Vishnu Nandan, a postdoctoral research associate at the University of Calgary, is studying, along with Robbie Mallett of the University of Manitoba, different techniques that could improve the way radar satellites measure the thickness of the ice and snow of Antarctica.
His work is part of a British project aimed at establishing an advanced ground-based radar system that could mimic what satellites do in orbit.
“Actually, before we even arrived, we knew we wouldn’t have a lot of sea ice, because it’s been really warm recently,” Mr. Nandan said in a telephone interview while he was at the Rothera research station on the island of Adelaide, located almost 1900 kilometers south of the Falkland Islands.
PHOTO UNIVERSITY OF CALGARY BY THE CANADIAN PRESS
Vishnu Nandan
“When we arrived, we had the lowest sea ice ever recorded in recent decades. »
The problem, Nandan said, is that the region receives so much snow, sometimes up to a meter, that it is difficult to obtain accurate readings of snow and sea ice thickness with the satellites in orbit.
Researchers therefore collected ground data to improve satellite algorithms and thus produce precise measurements essential for projections related to climate change.
Significant decrease
Mr. Nandan conducted similar research a few years ago in the central Arctic Ocean. At the time, he boarded an icebreaker for a year to complete an in-depth study of global warming from an observation point near the North Pole.
Arctic sea ice has declined significantly — by about 70% over the past 30 to 40 years. In comparison, Antarctica has remained stable, but in recent years, since around 2016, there has been a dramatic decline in sea ice levels in many parts of Antarctica.
Vishnu Nandan, researcher
“What’s happening right now is serious. This is very serious. When you look at the overall sea ice area, it is almost a million square kilometers lower than the previous lowest level in 1986.”
While there is still a lot of snow, there are also several days of rain, which is unusual, said Nandan, who added that the warm wind prevents the ocean ice from freezing solid.
“Sea ice is white in color and reflects most of the sunlight that hits it,” he explained. If there is less sea ice, that means there is more open water, which absorbs most of the sunlight. »
The polar oceans are therefore becoming warmer, which can affect both the ecosystem and the weather.
“We are already seeing more climate disasters like tornadoes, cyclones and extreme weather phenomena like torrential rains,” he recalled. This affects the ecosystem…from alligators and microplankton, to animals like seals, which need sea ice for their habitat. »
Mr. Nandan has completed his stay in Antarctica and will return to Calgary in November. His work is also funded by the University of Manitoba.