caa a22 4500 60547267X CHVBK 20210128100339.0 cr unu---uuuuu 210128e20151101xx s 000 0 eng 10.1007/s00382-015-2494-4 doi (NATIONALLICENCE)springer-10.1007/s00382-015-2494-4 Eurasian snow cover variability and links to winter climate in the CMIP5 models [Elektronische Daten] [Jason Furtado, Judah Cohen, Amy Butler, Emily Riddle, Arun Kumar] Observational studies and modeling experiments illustrate that variability in October Eurasian snow cover extent impacts boreal wintertime conditions over the Northern Hemisphere (NH) through a dynamical pathway involving the stratosphere and changes in the surface-based Arctic Oscillation (AO). In this paper, we conduct a comprehensive study of the Eurasian snow-AO relationship in twenty coupled climate models run under pre-industrial conditions from the Coupled Model Intercomparison Project Phase 5 (CMIP5). Our analyses indicate that the coupled climate models, individually and collectively, do not capture well the observed snow-AO relationship. The models lack a robust lagged response between October Eurasian snow cover and several NH wintertime variables (e.g., vertically propagating waves and geopotential heights). Additionally, the CMIP5 models do not simulate the observed spatial distribution and statistics of boreal fall snow cover across the NH including Eurasia. However, when analyzing individual 40-year time slices of the models, there are periods of time in select modelswhen the observed snow-AO relationship emerges. This finding suggests that internal variability may play a significant role in the observed relationship. Further analysis demonstrates that the models poorly capture the downward propagation of stratospheric anomalies into the troposphere, a key facet of NH wintertime climate variability irrespective of the influence of Eurasian snow cover. A weak downward propagation signal may be related to several factors including too few stratospheric vortex disruptions and weaker-than-observed tropospheric wave driving. The analyses presented can be used as a roadmap for model evaluations in future studies involving NH wintertime climate variability, including those considering future climate change. Springer-Verlag Berlin Heidelberg, 2015 Arctic Oscillation nationallicence Large-scale extratropical climate variability nationallicence Stratosphere-troposphere coupling nationallicence Eurasian snow cover nationallicence Furtado Jason Atmospheric and Environmental Research, Inc., 131 Hartwell Ave., 02421, Lexington, MA, USA aut Cohen Judah Atmospheric and Environmental Research, Inc., 131 Hartwell Ave., 02421, Lexington, MA, USA aut Butler Amy Earth Systems Research Laboratory, Chemical Sciences Division, Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA aut Riddle Emily Climate Prediction Center, NOAA, College Park, MD, USA aut Kumar Arun Climate Prediction Center, NOAA, College Park, MD, USA aut Climate Dynamics Springer Berlin Heidelberg 45/9-10(2015-11-01), 2591-2605 0930-7575 45:9-10<2591 2015 45 382 https://doi.org/10.1007/s00382-015-2494-4 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00382-015-2494-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Furtado Jason Atmospheric and Environmental Research, Inc., 131 Hartwell Ave., 02421, Lexington, MA, USA aut NATIONALLICENCE 700 1- Cohen Judah Atmospheric and Environmental Research, Inc., 131 Hartwell Ave., 02421, Lexington, MA, USA aut NATIONALLICENCE 700 1- Butler Amy Earth Systems Research Laboratory, Chemical Sciences Division, Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA aut NATIONALLICENCE 700 1- Riddle Emily Climate Prediction Center, NOAA, College Park, MD, USA aut NATIONALLICENCE 700 1- Kumar Arun Climate Prediction Center, NOAA, College Park, MD, USA aut NATIONALLICENCE 773 0- Climate Dynamics Springer Berlin Heidelberg 45/9-10(2015-11-01), 2591-2605 0930-7575 45:9-10<2591 2015 45 382