Scientists in the polar regions have been watching temperature changes closely because of global warming. The territory is a hazard waiting to be unleashed because, as climate change gets worse, the poles could release vast amounts of carbon as they thaw. Among these scientists is a team from the Australian Antarctic Program stationed in East Antarctica who has just recorded the first reported heatwave event at Casey research station during the 2019–2020 summer. They expect it will have significant impacts on the ecosystem there. The research has been published in the journal Global Change Biology.
Dr. Sharon Robinson, a University of Wollongong biologist and author of the study, wrote that Casey recorded its highest ever minimum and maximum temperatures between 23 and 26 January of 2020. She said:
“Heatwaves are classified as three consecutive days with both extreme maximum and minimum temperatures. In those three days in January, Casey experienced minimum temperatures above zero and maximum temperatures above 7.5°C, with its highest maximum temperature ever, 9.2°C on 24 January, followed by its highest minimum of 2.5°C the following morning. In the 31-year record for Casey, this maximum is 6.9°C higher than the mean maximum temperature for the station, while the minimum is 0.2°C higher.”
Research bases on the Antarctic Peninsula also recorded record high temperatures in February. The average daily temperature there exceeded that month’s long-term means by 2°C to 2.4°C. The two events are not related, but they show how the entire continent is heating up due to climate change, part of a broader pattern in which marine heatwaves are growing more frequent and more intense. The warmer summers affecting Antarctica overall will most likely lead to long-term disruption to communities, local populations, and the broader ecosystem, explained Australian Antarctic Division applied Antarctic ecologist Dr. Dana Bergstrom. She said:
“Most life exists in small ice-free oases in Antarctica, and largely depends on melting snow and ice for their water supply. Meltwater flooding can provide additional water to these desert ecosystems, leading to increased growth and reproduction of mosses, lichens, microbes, and invertebrates. However excessive flooding can dislodge plants and alter the composition of communities of invertebrates and microbial mats. If the ice melts completely, early in the season, then ecosystems will suffer drought for the rest of the season. Higher temperatures could also cause heat stress in some organisms.”
Some organisms that aren’t used to the higher temperatures may suffer from heat stress. The team expects that there will be long-term consequences for the continent due to this year’s hot summer season. However, the precise biological impacts are yet unknown. The scientists will continue to monitor the region to gauge the consequences.
