It's not quite a cold day in Hell, but it seems we'd better get used to the idea of hot times in Antarctica after Esperanza Base set continental records two days in a row.
It's true that the 17.5°C (63.5°F) on Tuesday, March 24—following 17.4°C (63.4°F) at Base Marambio the day before—would come as a welcome relief for inhabitants of tropical regions. However, both figures are higher than Antarctica's previous recorded maximum of 17°C, (62.6°F). While records will always fall eventually, the latest reading is particularly noteworthy for happening after the continent's autumn equinox, a time of year when temperatures are normally well past the annual peak.
The majority of Antarctica has not experienced the same warming that the rest of the planet has had over the last five decades, a consequence of ozone depletion and ocean currents around the continent. The Antarctic Peninsula, already the warmest part of the continent, is the exception. Average temperatures there have warmed almost four times as fast as the planet as a whole since 1900, at rates completely out of keeping with previous changes recorded in the region's snow.
The consequences have been written in the near total collapse of the Larsen B Ice Shelf and the devastation of local ecosystems. Despite this increase in averages, the record—set in 1976—survived until last week.
Credit: U.S. Geological Service. Esperanza Base sits in Graham Land, north of the Antarctic Circle.
Weather Underground notes that high temperatures have not been restricted to Antarctica, with three other countries and a French overseas territory tying or breaking records already in 2015. Cold as it has been in parts of North America, no national low temperature record has been set anywhere this year.
The high pressure ridge that created the conditions for the warm temperatures trapped a cut-off low over Chile, bringing 14 times the annual average rainfall to the Atacama Desert in a single day.