Antarctica becomes less and less recognizable every year. Scientists have found that on land, flowering plants, mosses and algae are spreading like never before, while at sea, the area of ​​floating sea ice has reached a record low. These dramatic changes coincided with rising summer temperatures. In 2022, University of Washington (UW) researchers recorded the largest heat wave ever to hit Antarctica.

In March, temperatures near the South Pole reached 39 °C above normal for three consecutive days, peaking at −10 °C (14 °F).

“This was the highest temperature anomaly ever recorded anywhere in the world,” atmospheric scientist Edward Blanchard-Wrigglesworth, first author of the UW team’s published paper, told Kashi Patel. washington post.

Some of his team working in Antarctica at the time wore shorts or even went out in the sun without a shirt. Moments like these reveal more than ever that Antarctica is not immune to the climate crisis, as some scientists once believed. To understand how much of Antarctica’s recent heat wave was due to climate change, the UW team used a “story approach.”

This modeling strategy relies on “the deployment of past events or possible future events or pathways” to reconstruct current climate events.

“We found that climate change over the last century increased heatwaves by 2°C, whereas the equivalent heatwave in 2096 would be 6°C warmer compared to 2022 (8°C compared to 1922)” – write Blanchard. Rigglesworth and colleagues.

This future scenario could see March temperatures in Antarctica getting dangerously close to melting point, threatening the continent’s vast ice sheets. Currently, Antarctica and its islands are covered by permanent snow and ice, and only one percent of the land is suitable for flowering plants such as Antarctic hairwort (Deschampsia antarctica) and Antarctic pearlwort (Colobanthus quinsis).

But warm springs and summers in the past few decades have caused such plants to become widespread, and growth rates increased by 20 percent or more from 2009 to 2018. According to some models, the area of ​​ice-free land available for plant colonization on the Antarctic Peninsula will triple by the end of the century.

Researchers worry that if vegetation continues to spread in these areas, it will lead to an “irreversible loss of biodiversity” in Antarctica.

“We know there will be thousands of square kilometers of new ice-free territory, and that warmer temperatures and additional water will create new habitats suitable for colonization, benefiting some species but not others,” said Jasmine Lee, a conservation biologist. In the British Antarctic Service in 2022.

“Unfortunately, a milder climate will also reduce the barrier to invasion by alien plant and animal species.”

Now scientists around the world are working as fast as they can to understand Antarctica’s past and current habitats in order to preserve them for the future. Source