New research indicates that the significant decline of Antarctic sea ice in 2023 may lead to increased storm activity in the Southern Ocean.
Scientists observed that the reduction in sea ice coverage resulted in the ocean losing excess heat to the atmosphere. This heat loss could disrupt ocean circulation currents, potentially causing more frequent storms in regions where sea ice has diminished.
In 2023, Antarctic ice coverage decreased by nearly 50% compared to the average levels recorded between 1990 and 2015. Four specific areas were affected: the Bellingshausen Sea and the outer Weddell and Ross seas, where ice coverage dropped by up to 80%, and Enderby Land, which experienced a decline of up to 50%.
Simon Josey, an oceanographer at the National Oceanography Centre in the U.K. and co-author of the study, emphasized that while it is premature to conclude that 2023 marks a fundamental shift in Antarctic sea ice levels, the extreme conditions observed may indicate future trends.
The research, published on December 18 in the journal Nature, analyzed heat flux between the air and sea and changes in ice coverage. It revealed that the newly exposed ocean surface lost heat at a rate nearly one and a half times faster than in previous years.
This accelerated heat loss could have significant consequences. The cooling of surface waters, caused by heat loss, increases their density, leading to sinking. This process may disrupt deeper ocean currents and circulation patterns in the Southern Ocean.
Andrew Meijers, another co-author and oceanographer with the British Antarctic Survey, noted that this cooling effect could release warmer waters from deeper layers that are typically insulated by sea ice, potentially accelerating future sea ice melt.
Additionally, changes in heat flux between the ocean and atmosphere may contribute to a rise in storm frequency over Antarctica. The study found that regions experiencing ice loss had an average of 11.6 stormy days in June and July 2023, compared to 9.1 stormy days recorded between 1990 and 2015. Some areas, such as the northern Weddell Sea, experienced an increase of up to seven additional stormy days per month.
Researchers stress the importance of continued studies on the relationship between Antarctic sea ice loss, ocean heat loss, and shifting weather patterns, as these changes could have far-reaching effects on global weather and climate.