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A record-breaking temperature was recorded in Antarctica just a few days back. The French-Italian research station Concordia, located over 3,000 meters above sea level on the Antarctic Plateau, the coldest place on earth, recorded a temperature of 40ºC above average. At this time of year temperatures of around -55ºC are usual, but on March 18 the mercury hit -12ºC. Although it was cold, it wasn’t as cold as you would expect. Despite there being no ice melt, Sentinel satellite images showed that the Totten Glacier and its surroundings were experiencing high temperatures. They also saw darker snow, which indicates older layers. Meanwhile, in the Arctic, there is a HeatwaveThis has been recorded temperatures up to 30ºC higherIt was higher than the March average and in the absence sun.
Both the Arctic and Antarctic are breaking temperature records. This is putting into question the legitimacy of even the Antarctic. Most pessimistic climate model predictions. Scientists predict that by the end of the century, the number of polar heatwaves in the western Antarctic will double and triple in the interior of the eastern Antarctic. This is despite moderate climate change. These predictions were published in NatureRecent events have done little to mitigate them. Higher temperatures are becoming more common in the Arctic.
The consequences are well-known: Scientists have predicted that catastrophic polar melt will result in sea level rises across the globe. This will also disrupt ocean currents. Life as we know it has been transformed.By putting at stake the fragile ice balance in both the Arctic and the western Antarctic.
“Generally, both pole surges are related to climate change, but they are not connected; it’s normal they have ended up coinciding in time because the in the Arctic they are increasingly frequent, but what is staggering is their breadth, especially in Antarctica. Forty degrees of difference over the average is a lot,” says scientist Raúl Cordero, from the University of Santiago, Chile, and one of the authors of the Nature paper.
This is not an isolated event. Cordero notes that on January 7 a temperature of 11.4ºC was recorded at the Argentine Belgrano II research station, located in the Weddell Sea, and a month later, on February 8, another huge spike was recorded on the Antarctic Peninsula (13.7ºC at the South Korean King Sejong base and as high as 12ºC at the Ukrainian Vernadsky Research Base), which caused the collapse of an ice shelf measuring 3,800 square kilometers. Although these temperatures fall short of the record 18.2ºC recorded two years ago, the fact that this austral summer has seen the fewest ice floes in the region in 45 years, experts are not optimistic about the overall panorama.
“Heatwaves can cause significant ice melt and an increase in rain and snow. This means more snow in the Antarctic interior. But, on the coasts it can bring rain and melting. That is exactly what is happening right now. In the future, there will be more snowfall, but melting will increase significantly. These episodes also increase the instability and permeability of the icecliffs. The heat causes snow to melt inside. When it refreezes, it applies pressure to the walls, causing them to disintegrate. This can accelerate the loss in ice mass. In Antarctica, forecasts predict sea levels will rise by one to 1.7m by 2100,” says researcher Irina Gorodetskaya of the University of Aveiro and lead author of the sixth assessment report published by the Intergovernmental Panel on Climate Change (IPCC).
Satellite images showed that the 1,200-kilometer Conger ice shelf in East Antarctica had collapsed just days after the heatwave. The shelf has been weakening across time and according to experts the recent high temperatures may have been the straw that broke the camel’s back.
Atmospheric rivers are the scientific explanation for the latest heatwave in an area that has seen less impact from climate change. It is noteworthy that not far from the Concordia research station is the Russian Vostok Station, where 40 years ago the lowest temperature ever recorded on earth was taken: -89ºC. “Eastern Antarctica has always been cold but in this instance an atmospheric river brought warmer and more humid air from Australian to Dome C, where Concordia is located, and it was trapped, causing a micro-greenhouse effect,” says Cordero.
“These warm air plumes tend not to extend that far due to a wall of circumpolar winds coming from the west that prevents them from getting in. It was an exceptional event,” says meteorologist Sergi González, a researcher with the Spanish State Meteorological Agency’s Antarctic team. “Now, the hole in the ozone layer strengthens these winds and, in March, this wall is also reinforced. It will have to be investigated, but what is significant is the accumulation of these types of events; at the end of the day there are more heatwaves than cold waves and even if there were no global climate change, their number would remain the same.”
Even when dealing only with particular episodes, it is the frequency and intensity of these anomalies over the past years that has raised alarm bells. Experts fear that even current climate change models, as compiled by the IPCC in their reports, could be underestimating the reality on the ground. “As we have seen with this recent heatwave in Antarctica, I would say the models are very conservative and the reality shows that Climate change is not a matter of the future but of the present. These extreme events are still not well understood and the climate models could be underestimating them,” says Gorodetskaya.
Climate change in Antarctica is not a new phenomenon. Thirteen of 17 meteorological stations that have been monitoring temperatures for more than 30 years have already seen an increase in their annual averages. Researchers predict that heatwaves in the eastern Antarctic will increase from nine to 25 days per year to the west peninsula, and nine to 18 days to the east. Temperatures will also increase, by up to 5ºC, although they are expected to remain below zero in the interior of the Antarctic Plateau.
“The projections show that not only will polar heatwaves increase in the future, but that every fraction of a degree in global warming will matter: the extreme temperatures that occur once every 50 years in a climate without human influence could now take place every 10 years, and a with a level of global warming of two degrees, they will be 14 times more frequent,” says Gorodetskaya. These projections are incorrect. The contaminating emission that causes these climate events continue to rise on a global level. The current international context doesn’t support drastic measures.
“If this differential of 40º had happened in the Antarctic peninsula, in just a few days there would have been a level of ice melt that would normally take years,” says Francisco Navarro, a glacier expert at the Technical University of Madrid. Navarro points to melting glaciers caused by the 2020 heatwave, which he has been following for decades on Livingston Island. “The thermal wave can penetrate to a depth of 15m within a year and if it is persistent, the problem is even greater.”
The Arctic heatwave has been less surprising than expected, as it is already experiencing an alarming rate of melt, almost three times that of the rest. There, these temperature rises have an immediate effect on the region’s inhabitants and indigenous fauna as well as increasing the risk of forest fires. In the Siberian Arctic, 38ºC was recorded in 2020 and in Greenland a year later, the mercury rose to 23.4ºC during a heatwave. This year, in the middle of winter and with no daylight hours, 0ºC has almost been reached in some areas.
The longer we wait the more severe the impact will be, and the longer the irreversibility period.
Irina Gorodetskaya, a researcher at University of Aveiro
“In the Antarctic, the impact is not so sensitive in immediate terms, but the fauna also suffers. Furthermore, we lack understanding of the so-called high-impact, low-probability episodes, such as a sudden collapse of the West Antarctic ice sheet, but the consequences of sea-level rise and the destabilization of the climatic system will be enormous, if not catastrophic,” says Gorodetskaya, who in a few days will travel to the region for a research mission on the German-built High Altitude and Long-Range Research Aircraft (HALO). “We will fly along the warm air intrusions to measure the transformation of that air mass along its path. I want to look at the transition from snowfall to rainfall in atmospheric rivers in the Arctic and Antarctic,” the scientist says. The HALO was recently deployed to fly through a “river of warm air” that has reached Greenland from Canada.
Gorodetskaya isn’t optimistic about whether we can revert to pre-global climate change in the polar region. “We can slow it down, but the response of the Antarctic system is irreversible. Even if it is slowed down or stopped for 100, 1,000 or more years, the impact will not be reversed. Each additional degree of heatwave and temperature increase will force future generations to take responsibility for so-called negative emission, which is reducing carbon in our atmosphere. This commitment can be made even after human-caused emissions have reached zero. Because Arctic sea ice changes are linearly related to global surface temperatures, they can be reversed. There is no tipping point. But the longer we wait, the greater the impact will be and the longer the period of irreversibility will also be.”
All experts agree that the Arctic and Antarctic phenomena must be studied and understood better. But, it is crucial that we take immediate action to stop the emission.
