Heat records have been reported from various measuring points in East Antarctica in the past few days. Temperatures have been more than 30 degrees higher than the long-term average in many places since the end of the week, several times. At the Russian research station Vostok, for example, where the lowest temperature ever measured on earth was recorded at -89.3 degrees Celsius in the Arctic winter of 1983, it was -17.7 degrees last Friday. It’s warmer than it’s been in the past 63 years since temperatures have been recorded there. At this time of year, the average temperature there is usually -53 degrees Celsius. The previous maximum temperature in March was well below -30 degrees.
With the approaching end of the Antarctic summer, the temperatures around the South Pole should actually be falling drastically. The current event is “completely unprecedented”, said Jonathan Wille, a geoscientist at the University of Grenoble Washington Post“It turned our expectations of the Antarctic climate system upside down”https://www.sueddeutsche.de/wissen/.”I haven’t seen anything comparable before,” says glaciologist Ted Scambos from the University of Colorado.
Wille sees a connection between the current developments in Antarctica and the extraordinary heat wave that hit Canada and parts of the USA last summer. At the time, climatologists had calculated that this would have been practically impossible without the influence of global warming. Experts think it likely that the high temperatures in Antarctica were triggered by a current in the atmosphere that was pumping moist, warm air south from the Pacific. These air masses hit the continent last Tuesday and brought heavy precipitation.
A high-pressure system had blocked the humid air masses over East Antarctica before the weekend, which is why they could not flow out. Experts expected that this system would collapse over the course of the weekend and the warm air could eventually escape. Wille says warm air is more often channeled over Antarctica in this way, but never so intensely. “We’ve never seen anything like it before.”
Whether the heat wave in Antarctica was actually triggered by climate change cannot be proven. However, heat waves are becoming more frequent and more intense worldwide due to global warming. The polar caps heat up even faster than the rest of the world. The extent of Antarctic sea ice also reached its lowest point since records began in 1979 this February. For the month as a whole, the extent of the ice was 27 percent below the average for the years 1991 to 2020. Satellite measurements show that some glaciers in Antarctica are melting faster than in the Alps.