The Wave that Warmed the Coldest Place on Earth: Antarctica’s First-Ever Heatwave

Beginning early in the spring of 2020, a heatwave swept over Antarctica. As if global warming wasn’t already a major concern! Circumnavigating the continent through the next four months, the icy continent saw temperatures skyrocket well beyond the usually frigid temperatures.

With massive amounts of snow turning into ponds, the heatwave has changed the landscape of the continent. The warning bells are ringing loud and clear as even the coldest continent on Earth wasn’t spared by the effects of human pollution.

Despite its geographical isolation from other continents, it has a significant effect on the rest of the world. Ice sheets melting in Antarctica add to the rise in the global sea level, and the continent also has an impact on the global ocean conveyor belt, a system that facilitates the transfer of oceanic heat across the planet.

The heatwave is of particular significance as climatic changes in Antarctica can be thought of as a prelude of sorts to the patterns of change that we are likely to see in other places on the planet.

A Heatwave in the Cold
According to Dr Sharon Robinson, a biologist, heatwaves are classified as three consecutive days with both extreme maximum and minimum temperatures. Between January 23-26, researchers from the Australian Antarctic Program recorded Antarctica’s first ever heatwave at the Casey Research Station in the Windmill Islands oasis. For three days at a stretch, minimum temperatures were well above zero while the maximums all exceeded 7.5°C. In the wake of the warmer climate, Davis Research Station experienced rain, snowbanks melted and flooded lake and by February temperatures hit a new all-time high.

With most of the heat centred around the Antarctic Peninsula in the North, on February 6, a temperature of 18.4°C was recorded at Esperanza Station – almost 1°C higher than the previously held record for maximum temperatures. As the heatwave peaked, the snowpack on Eagle Island melted by about 4 inches, which approximately amounts to 20% of the island’s snow. Images from NASA revealed huge pools of melted water in areas where there had once been snow.

Though melts like these haven’t been uncommon to other places like Alaska and Greenland, they have remained an unusuality to Antarctica, that is, up until 2020 rolled
around.

The heatwave is of particular significance as climatic changes in Antarctica can be thought of as a prelude of sorts to the patterns of change that we are likely to see in other places on the planet.

How it happened
Despite the pretty glaring evidence of global warming across the globe, the general pace of climate change has been slower in most parts of Antarctica on account of the ozone hole which has been in place since the late 70s. According to, Dr Dana Bergstrom, an Antarctic ecologist, the ozone hole, by strengthening jet stream winds over the Southern Ocean, created a kind of seasonal shield which reduced the transfer of warm air from the earth’s temperate regions to Antarctica. As the stratosphere has gotten warmer, however, the size of the hole has reduced over time, thus weakening the shield.

Other factors, according to scientists, may have had something to do with the warmer than usual waters in the Western Indian Ocean, caused by a late retreat of the Indian monsoon towards the end of 2019. According to them, the air rising from the Indian Ocean along with other warm ocean patches in the Pacific Ocean provided energy sources that caused changes in weather systems. This, in turn, helped to disrupt and warm the stratosphere.

The Good, The Bad and The Unknown
The mostly ice-covered continent is dotted by small ice-free oases which make up the biodiversity hotspots that house a variety of flora and fauna – mosses, lichen, penguins and much more. Much like the Disney Ice Queen, the snow never bothered them anyway. The heat, however, is already causing a change to the continent’s biodiversity–both good and bad.
The localised flooding, for instance, seems to have benefited some moss banks in Vestfold Hills. Previously grey and debilitated, many moss shots have turned green post the flooding. The warmer conditions have created more ponds of liquid water which, considering the normally cold climate of the continent, may have worked in favour of the flora, microbes and invertebrates in those areas.
Though the increased availability of meltwater can act as an extra water source for these organisms, it could also end up dislodging plants and causing serious changes to the composition life on the continent. The higher temperatures may have also resulted in heat stress in some organisms, which occurs once temperatures rise above 10°C.
Climate systems are connected, and extreme changes in one part of the globe are likely to have an impact in other parts of the planet as well. It is difficult to predict the exact impact of the heatwave as of now and all that can be done is to wait and watch. Bergstrom states, “Based on our experience from previous anomalous hot Antarctic summers, we can expect many biological impacts, positive and negative, in coming years.”
Climate change has sunk its claws in deep. And we now know that not even the coldest place on Earth is exempt from what it holds for us in the future.