«Never seen a similar drop in 35 years»- Corriere.it

In Antarctica the summer season is coming to an end, a period during which sea ice reaches its minimum extent. This year to been touched the all-time low ice-covered area around the Antarctic continent: 2.11 million square kilometers on 15 February, according to the findings of the SeaIce Portal, which analyzes the trend of the frozen area day by day. Thanks also to the lesser extent of the ice, in recent weeks the Italian icebreaker Laura Bassi it was able to reach the southernmost point ever reached by a boat in history.

The new minimum

alreadyBy February 8, southern sea ice extent had fallen below an all-time low, which was registered only last year. The rapid decline recorded over the past six years very surprising because the extent hadn’t changed much in the previous 35 yearssaid Christian Haas, a Wegener Institute professor at the Helmholtz Center for Polar Studies and head of the glacial section. We need to understand if the current phase is the beginning of the rapid end of summer sea ice at the South Pole or if instead it is a situation that will lead to a new lower level but still with the presence of ice in the summer season.

The variations

Over the course of the year, sea ice in Antarctica goes from a maximum extent that is reached between September and October, and a minimum in February. The maximum area reaches 18-20 million square kilometers. Until December 2022, the melting of the frozen pack ice had been very intense in the sectors of the Bellinghausen and Amundsen seas, then it also extended to the sectors of the Pacific Ocean, the Indian Ocean and the Ross Sea (in the latter there Laura Bassi). However, the presence of ice in the Weddell Sea resisted.

The influence of the winds

According to scientists, the loss of southern sea ice is not only due to the global warming in s (about 1.5 C more than the average recorded in the Antarctic peninsula) which causes the water temperature to increase, but also to changes in the direction of the prevailing winds around the continent. A change that is also due to climate change. However, the presence or absence of sea ice intensely affects the ecosystem of the entire Antarctic Ocean because it alters the production of phytoplankton, which forms the basis of the food chains of animals such as whales, killer whales, fish, seals and penguins.