New Measurements Show Greater Warming of the Southern Ocean

Nature Communications, January 21

New analysis of a rare time series of temperature data, collected over 25 years aboard the French Antarctic station’s resupply vessel L’Astrolabe in the portion of the Southern Ocean that separates Australia and Antarctica, shows rapid ocean warming beneath the surface layers of water circling Antarctica, at a rate of 0.3°C warming per decade. In parallel, this warm water is also soaring towards the surface three to ten times faster than previously estimated. The rate of change observed aboard L’Astrolabe is comparable to that observed by other measuring efforts in the Amundsen and Bellingshausen seas bordering the West Antarctic Ice Sheet, where Antarctica’s fastest ice loss is occurring today. Such levels of warming waters, especially as these rise closer to the surface can melt ice from underneath ice shelves and marine-based ice sheets, increasing the potential for ice sheet instability and sudden collapse, with implications for relatively rapid acceleration of global sea-level rise.

https://www.nature.com/articles/s41467-020-20781-1

Compiled by Amy Imdieke.