North American Climate in CMIP5 Experiments. Part II: Evaluation of Historical Simulations of Intraseasonal to Decadal Variability

Authors

Justin Sheffield, Princeton UniversityFollow
Suzana J. Camargo, Columbia University
Rong Fu, The University of Texas at Austin
Q. Steven Hu, University of Nebraska-LincolnFollow
Xianan Jiang, University of California, Los Angeles
Nathaniel Johnson, University of Hawaii at Manoa
Kristopher Karnauskas, Woods Hole Oceanographic Institution
Seon Tae Kim, CSIRO Marine and Atmospheric Research
Jim Kinter, Center for Ocean–Land–Atmosphere Studies
Sanjiv Kumar, Center for Ocean–Land–Atmosphere Studies
Baird Langenbrunner, University of California, Los Angeles
Eric Maloney, Colorado State University, Fort Collins
Annarita Mariotti, National Oceanic and Atmospheric Administration/Office of Oceanic and Atmospheric Research
Joyce E. Meyerson, University of California, Los Angeles
J. David Neelin, University of California, Los Angeles
Sumant Nigam, University of Maryland, College Park
Zaitao Pan, Saint Louis University
Alfredo Ruiz-Barradas, University of Maryland, College Park
Richard Seager, Columbia University
Yolande L. Serra, The University of Arizona
De-Zheng Sun, University of Colorado
Chunzai Wang, NOAA/Atlantic Oceanographic and Meteorological Laboratory
Shang-Ping Xie, University of Hawaii at Manoa
Jin-Yi Yu, University of California, Irvine
Tao Zhang, University of Colorado
Ming Zhao, NOAA/Geophysical Fluid Dynamics Laboratory

Date of this Version

2013

Citation

Sheffield Et Al. (1 DECEMBER 2013); DOI: 10.1175/JCLI-D-12-00593.1

Comments

Copyright 2013 American Meteorological Society

Abstract

This is the second part of a three-part paper on North American climate in phase 5 of the Coupled Model Intercomparison Project (CMIP5) that evaluates the twentieth-century simulations of intraseasonal to multidecadal variability and teleconnections with North American climate. Overall, the multimodel ensemble does reasonably well at reproducing observed variability in several aspects, but it does less well at capturing observed teleconnections, with implications for future projections examined in part three of this paper. In terms of intraseasonal variability, almost half of the models examined can reproduce observed variability in the eastern Pacific and most models capture the midsummer drought over Central America. The multimode mean replicates the density of traveling tropical synoptic-scale disturbances but with large spread among the models. On the other hand, the coarse resolution of the models means that tropical cyclone frequencies are under predicted in the Atlantic and eastern North Pacific. The frequency and mean amplitude of ENSO are generally well reproduced, although teleconnections with North American climate are widely varying among models and only a few models can reproduce the east and central Pacific types of ENSO and connections with U.S. winter temperatures. The models capture the spatial pattern of Pacific decadal oscillation (PDO) variability and its influence on continental temperature and West Coast precipitation but less well for the wintertime precipitation. The spatial representation of the Atlantic multidecadal oscillation (AMO) is reasonable, but the magnitude of SST anomalies and teleconnections are poorly reproduced. Multidecadal trends such as the warming hole over the central–southeastern United States and precipitation increases are not replicated by the models, suggesting that observed changes are linked to natural variability.