Analysis of weather station and satellite data, showing the continent-wide warming trend from 1957 through 2006.
Eric J. Steig (University of Washington), David P. Schneider (National Center for Atmospheric Research), Scott D. Rutherford (Roger Williams University), Michael E. Mann (Pennsylvania State University), Josefino C. Comiso (NASA Goddard Space Flight Center), and Drew T. Shindell (NASA Goddard Institute for Space Studies and Columbia University)
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