Articles | Volume 2, issue 4
Research article
16 Dec 2021
Research article |  | 16 Dec 2021

Impact of Eurasian autumn snow on the winter North Atlantic Oscillation in seasonal forecasts of the 20th century

Martin Wegmann, Yvan Orsolini, Antje Weisheimer, Bart van den Hurk, and Gerrit Lohmann

Data sets

Public Datasets European Centre for Medium-Range Weather Forecasts

North Atlantic Oscillation Climatic Research Unit

Initialised seasonal forecast of the 20th Century Centre for Environmental Data Analysis

Short summary
Northern Hemisphere winter weather is influenced by the strength of westerly winds 30 km above the surface, the so-called polar vortex. Eurasian autumn snow cover is thought to modulate the polar vortex. So far, however, the modeled influence of snow on the polar vortex did not fit the observed influence. By analyzing a model experiment for the time span of 110 years, we could show that the causality of this impact is indeed sound and snow cover can weaken the polar vortex.