Antarctic Sea Ice Reaches Lowest Level Recorded In History

Antarctic sea ice reaches lowest level recorded in history

Ice melting

The Antarctic ice shelf’s maximum surface area for this season is the lowest ever recorded since scientific surveys began.

Antarctic sea ice typically melts in summer and replenishes in winter, which is currently ending in the Southern Hemisphere. According to the National Snow and Ice Data Center (NSIDC), located in Colorado, on September 10, the Antarctic Sea ice reached its maximum annual extent, measuring 16.96 million km². This represents the lowest level recorded from 1979 to 2023, by a significant margin.

This year’s maximum extent is 1.03 million km² less than the previous record low, which is nearly twice the size of France.

During the austral summer in February, the Antarctic Sea ice reached its smallest surface area, recording a minimum extent of 1.79 million km², a new melting record. Subsequently, it reformed at an unusually slow rate, despite the onset of winter.

In the Arctic, where summer is ending, the sea ice has also reached its smallest extent for the year, measuring 4.23 million km². This marks the sixth lowest extent recorded in the past forty-five years.

For several decades, the surface area of Antarctic Sea ice remained stable or slightly expanded. However, since August 2016, there has been a sharp and consistent downward trend in Antarctic Sea ice extent almost every month.

The exact cause of this trend is debated among scientists, and they are cautious about directly attributing it to global warming, as climate models have struggled in the past to predict changes in Antarctic Sea ice. Since 2016, the trend appears to be associated with the warming of the upper ocean layer. There is concern that this trend could signify a long-term decline in Antarctic Sea ice as oceans warm globally.

While the melting of Antarctic Sea ice does not have an immediate impact on sea levels (since it is sea water), the reduced whiteness of the ice reflects less of the Sun’s rays compared to the darker ocean surface, thereby exacerbating global warming. The absence of ice could also expose Antarctica’s coasts to waves, which could destabilize the ice sheet composed of freshwater, potentially leading to a catastrophic rise in sea levels.