Polar oceans transformed as warming melts ice habitats

PARIS

Climate change is increasingly reshaping the polar oceans, with Arctic waters warming rapidly, sea ice shrinking and wildlife losing habitat at both ends of the planet, an annual report said on Sept. 30.

The Copernicus Ocean State Report depicts profound changes across the world’s seas, from record-breaking heatwaves in the Mediterranean and Black seas to shifts in marine ecosystems and increasingly acidic waters.

“The message is very clear. The ocean is changing rapidly,” said Pierre Bahurel, director general of Mercator Ocean International, which runs the European Union’s Copernicus Marine Service.

Some of the more dramatic effects from global warming are taking place in the poles, which occupy around 20 percent of the global ocean surface.

The Arctic’s combined sea surface and sea-ice surface temperature rose 4.2 degrees Celsius between 1982 and 2024, or around 1 degree per decade, according to the 10th annual oceans report.

By comparison, global sea surface temperatures have been increasing by 0.12 degrees per decade.

As temperatures rise, Arctic sea ice has shrunk by nearly half a million square kilometers per decade since 1979, equivalent to losing an area the size of Spain every 10 years.

The retreating ice exposes Arctic coastlines to waves, worsening coastal erosion and raising risks for coastal communities and infrastructure, the report warned.

“The Arctic sea ice has been declining since the early 80s, leaving around 60 percent of coastal infrastructure vulnerable to erosion and sea level rise,” Karina von Schuckmann, director of the oceans report, said in a media briefing.