Growing Intense Arctic Marine Heatwaves Linked to Sea Ice Loss

Nature Climate Change, 6 January 2025

Rising temperatures have increased the frequency of extreme ocean warming events around the world, and the rapid decline of Arctic sea ice in recent decades makes these waters particularly vulnerable to sudden and extreme temperature fluctuations. Sea ice historically protected the Arctic Ocean from such warming events by serving as a natural buffer. In this study, high-resolution climate models show that Arctic marine heatwaves will not only occur more frequently in the future, but will also vary greatly in intensity from year to year as sea ice declines. Rising ocean temperatures will also alter the structure of the Arctic Ocean, making the water column more stratified: with a warmer water layer at the surface that cuts off mixing with the colder and denser water below. This phenomenon will prevent essential nutrients from reaching some levels of the water column — a vital process that currently provides the foundation of the Arctic ecosystem.

Full paper: https://doi.org/10.1038/s41558-024-02224-7
Coverage by The Barents Observer: https://www.thebarentsobserver.com/climate-crisis/rising-frequency-and-intensity-of-marine-heatwaves-threaten-arctic-ecosystems-study/422877