Antarctic ice is melting faster than expected: first attempt at an explanation

2023-08-04 11:35:04

Sea ice is not only important as a reflection and insulation layer for the climate – but also a popular resting place for leopard seals, seals and penguins. Image: picture alliance / WILDLIFE

The extremely small area of ​​sea ice around Antarctica is increasingly worrying polar researchers. The ice landscape is changing more abruptly than ever since measurements began. A system change, climate change? There are now first attempts at an explanation.

Much of this year’s weather and climate is puzzling, but few are as puzzling as the occurrence of sea ice around Antarctica. In search of explanations, the researchers poke around in the fog. They have been registering record-breaking declines for more than half a year. Since measurements began, the area of ​​ice off the 18,000-kilometer Antarctic coast has never been so thin at the end of February, and this gap in sea ice has also increased in winter.

Joachim Müller-Jung

Editor in the feuilleton, responsible for the “Nature and Science” department.

In the meantime, more than two and a half million square kilometers of sea ice are missing, if one compares the current extent of the ice with the calculated long-term mean. What’s more, this year’s deviation has reached an unprecedented level compared to the average for the years 1981 to 2010: more than 6.5 sigma in deviation downwards. If you convert these six and a half standard deviations from the calculated mean, this corresponds to a probability of occurrence of less than one in a billion. In other words, it is an extremely rare, almost impossible event under stable conditions.