Recent winter warming in continental West Antarctica is caused by rising sea surface temperatures in the tropical Pacific Ocean, suggests a study online this week in Nature Geoscience. This warming in West Antarctica is linked to tropical Pacific temperatures through changes in the atmospheric circulation.

Eric Steig and colleagues analysed observations of surface temperature from Antarctica and the global oceans along with atmospheric circulation data to identify the influence of Pacific sea surface temperatures on atmospheric dynamics, which brings warmer air to West Antarctica during the winter. They also perform climate model simulations to confirm this relationship between the climate in the tropics and high latitudes.