According to climatologists, the sea ice area in Antarctica has reached a record low since satellite observations began 45 years ago. At present, the sea ice area in the southern part of the ocean is about 2.6 million square kilometers, which is almost four times the area of Texas.
This unprecedented event has reached 6.4 standard deviations from the 1991-2020 average, indicating that it is an extremely rare event. Ocean physicist Edward Doddridge calls this event a “six-sigma” event, meaning that if nothing changes, we would expect to see a winter like this about once every 7.5 million years.
The reason for this extreme melting of sea ice is not yet clear, but scientists believe that the climate crisis is most likely to blame. Antarctica’s ice is melting in ways that climate models did not predict. The southern ocean surface has cooled slightly while deeper parts have warmed as global atmospheric temperatures have risen due to fossil fuel emissions. This discrepancy highlights the lack of understanding of how ocean, ice and atmosphere interact in the Southern Hemisphere.
One possible explanation for the sudden breakup of Antarctica’s sea ice in 2016 is the impact of increasingly warm winds in the region. These warm winds, combined with stormy westerly winds driven by the El Niño transition, likely destroyed a significant amount of new sea ice that normally forms during winter. However, this explanation does not fully explain the extent of sea ice loss.
Another factor contributing to ice melt is the influx of warm water, which can eat away at icebergs from below. The absence of sea ice could also have led to an increase in air temperature near the surface, which further warmed the surface water and prevented ice formation.
Scientists are now trying to understand the complex interplay between the climate crisis, ocean currents and sea ice in Antarctica. The record low sea ice extent emphasizes the need for further research and action to mitigate the effects of climate change on our planet.