HR: 16:20h
AN: GC24A-02 INVITED    [Abstracts]
TI: Attribution of the Regional Patterns of North American Climate Trends
AU: * Hoerling, M
EM: martin.hoerling@noaa.gov
AF: NOAA/ESRL, 325 Broadway R/PSD, Boulder, CO 80303,
AU: Kumar, A
EM: Arun.Kumar@noaa.gov
AF: Climate Prediction Center, NOAA/NCEP W/NP5 5200 Auth Road, WWBG, Camp Springs, MD 20746,
AU: Karoly, D
EM: dkaroly@unimelb.edu.au
AF: School of Earth Sciences, University of melbourne, Victoria, 3010, Australia
AU: Rind, D
AF: Goddard Institute for Space Studies, Columbia University, 2880 Broadway, New York, NY 10025-7848,
AU: Hegerl, G
EM: hegerl@duke.edu
AF: Dept. of Eath and Ocean Sciences, Duke University, Durham, NC 27708,
AU: Eischeid, J
EM: jon.k.eischeid@noaa.gov
AF: NOAA/ESRL, 325 Broadway R/PSD, Boulder, CO 80303,
AB: North American trends in surface temperature and precipitation during 1951-2006 exhibit large spatial and seasonal variations. We seek to explain these by synthesizing new information based on existing model simulations of climate and its forcing, and based on modern reanalyses that describe past and current conditions within the free atmosphere. The presentation focuses on current capabilities to explain the spatial variations and seasonal differences in North American climate trends. It will address whether various heterogeneities in space and time can be accounted for by the climate system's sensitivity to time evolving anthropogenic forcing, and examines the influences of non-anthropogenic processes. New findings are presented that indicate anthropogenic forcing alone was unlikely the cause for key regional and seasonal patterns of change, including the absence of summertime warming over the Great Plains of the United States, and the absence of warming during both winter and summer over the southern United States. Key regional features are instead attributed to trends in the principal patterns of atmospheric flow that affect North American climate. It is demonstrated that observed variations in global sea surface temperatures have significantly influenced these patterns of atmospheric flow.
DE: 1635 Oceans (1616, 3305, 4215, 4513)
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting