Inter-model diversity in jet stream changes and its relation to Arctic climate in CMIP5
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We examined how coupled general circulation models (CGCMs) simulate changes in the jet stream differently under greenhouse warming, and how this inter-model diversity is related to the simulated Arctic climate changes by analyzing the simulation of the Coupled Model Intercomparison Project Phase 5. Although the jet stream in the multi-model ensemble mean shifts poleward, a considerable diversity exists among the 34 CGCMs. We found that inter-model differences in zonal wind responses, especially in terms of meridional shift of the midlatitude jet, are highly dependent on Arctic surface warming and lower stratospheric cooling. Specifically, the midlatitude jet tends to shift relatively equatorward (poleward) in the models with stronger (weaker) Arctic surface warming, whereas the jet tends to shift relatively poleward (equatorward) in the models with stronger (weaker) Arctic lower stratospheric cooling.
KeywordsArctic amplification Jet stream Polar cap cooling
We acknowledge the World Climate Research Programme’s Working Group on Coupled Modelling, which is responsible for CMIP, and we thank the climate modeling groups (listed in Table 1 of this paper) for producing and making available their model output. For CMIP the U.S. Department of Energy’s Program for Climate Model Diagnosis and Intercomparison provides coordinating support and led development of software infrastructure in partnership with the Global Organization for Earth System Science Portals. This study was supported by Korea Meteorological Administration Research and Development Program under Grant KMIPA 2015-2092, and National Research Foundation (NRF-2014R1A2A2A01003827). H. S. Min was supported by Korea Institute of Ocean Science and Technology (PE99293).
- Bracegirdle TJ, Shuckburgh E, Sallee J-B, Wang Z, Meijers AJS, Bruneau N, Phillips T, Wilcox LJ (2013) Assessment of surface winds over the Atlantic, Indian, and Pacific Ocean sectors of the Southern Ocean in CMIP5 models: historical bias, forcing response, and state dependence. J Geophys Res Atmos 118:547–562. doi: 10.1002/jgrd.50153 CrossRefGoogle Scholar