Changing Northern Hemisphere Storm Tracks in an Ensemble of IPCC Climate Change Simulations

• Published in: Journal of climate Vol. 21; no. 8; pp. 1669 - 1679
• Main Authors: Ulbrich, U., Pinto, J. G., Kupfer, H., Leckebusch, G. C., Spangehl, T., Reyers, M.
• Format: Journal Article
• Language: English
• Published: Boston, MA American Meteorological Society 15-04-2008
• Subjects: Agreements; Anthropogenic factors; Archives & records; Atmospheric models; Baroclinic waves; Climate change; Climate models; Climatology; Climatology. Bioclimatology. Climate change; Cyclones; Data analysis; Deviation; Earth, ocean, space; Exact sciences and technology; External geophysics; General circulation models; Global climate; Global climate models; Greenhouse gases; Intergovernmental Panel on Climate Change; Meteorology; Modeling; Northern Hemisphere; Precipitation; Simulation; Simulations; Standard deviation; Storm tracks; Storms; Storms, hurricanes, tornadoes, thunderstorms; Studies; Trends; Weather; Wind; Winter; Winter storms; Northern Hemisphere; Europe; AN, North Atlantic; IN, USA, Alaska, Aleutian Is; IN, North Pacific; Ensemble simulation; Extratropical cyclone; Century 21st; General circulation models; Latitudinal variation; Climate models; Forecast model; trajectory; greenhouse gas; Dynamical climatology; Ocean-atmosphere model; Winter; Northern Hemisphere; Severe weather; global change; Forcing; storms; climate change; Anthropogenic factor; Baroclinic waves
• ISSN: 0894-8755; 1520-0442
• DOI: 10.1175/2007jcli1992.1

Winter storm-track activity over the Northern Hemisphere and its changes in a greenhouse gas scenario (the Special Report on Emission Scenarios A1B forcing) are computed from an ensemble of 23 single runs from 16 coupled global climate models (CGCMs). All models reproduce the general structures of the observed climatological storm-track pattern under present-day forcing conditions. Ensemble mean changes resulting from anthropogenic forcing include an increase of baroclinic wave activity over the eastern North Atlantic, amounting to 5%–8% by the end of the twenty-first century. Enhanced activity is also found over the Asian continent and over the North Pacific near the Aleutian Islands. At high latitudes and over parts of the subtropics, activity is reduced. Variations of the individual models around the ensemble average signal are not small, with a median of the pattern correlation nearr= 0.5. There is, however, no evidence for a link between deviations in present-day climatology and deviations with respect to climate change.