Rossby Wave - Poleward-propagating Atmospheric Rossby Waves

Poleward-propagating Atmospheric Rossby Waves

Deep convection and heat transfer to the troposphere is enhanced over anomalously warm sea surface temperatures in the tropics, such as during but by no means limited to El Niño events. This tropical forcing generates atmospheric Rossby waves that propagates poleward and eastward and are subsequently refracted back from the pole to the tropics.

Poleward propagating Rossby waves explain many of the observed statistical teleconnections between low latitude and high latitude climate, as shown in the now classic study by Hoskins and Karoly (1981). Pole-ward propagating Rossby waves are an important and unambiguous part of the variability in the Northern Hemisphere, as expressed in the Pacific North America pattern. Similar mechanisms apply in the Southern Hemisphere and partly explain the strong variability in the Amundsen Sea region of Antarctica. In 2011, a Nature Geoscience study using general circulation models linked Pacific Rossby waves generated by increasing central tropical Pacific temperatures to warming of the Amundsen Sea region, leading to winter and spring continental warming of Ellsworth Land and Marie Byrd Land in West Antarctica via an increase in advection.