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Researchers consider U.S. Southwest's response to warmer, drier conditions

November 24, 2001

In 2000, the popular press frequently referred to reports that the southwestern United States might experience a shift from relatively wet to dry conditions during the next couple of decades (see These predictions stemmed from observations that the Pacific Decadal Oscillation (PDO) appeared to abruptly change from a “positive” to a “negative” phase in 1999 (Figure 1). During the mid‐twentieth century, a similar negative phase of the PDO was accompanied by prolonged dry conditions in the southwest.

By extrapolation, some climatologists predicted future drought in the southwest. Such a change would heavily affect land use planning in the region, because national demographics have stressed the region's resources over the past century From 1990 to 2000, for instance, the population of Nevada and Arizona increased by almost 2.3 million people ( To discuss potential scenarios of landscape and ecosystem response to 25 years of hot and dry climate, scientists from diverse disciplines gathered at the University of Arizona in April 2001. The objectives of this workshop were to address evidence supporting predictions of warmer and drier climate and the possible landscape responses (‐workshop/).

Publication Year 2001
Title Researchers consider U.S. Southwest's response to warmer, drier conditions
DOI 10.1029/01EO00284
Authors Kevin M. Schmidt, Robert Webb
Publication Type Article
Publication Subtype Journal Article
Series Title Eos, Transactions, American Geophysical Union
Index ID 70216525
Record Source USGS Publications Warehouse
USGS Organization Geology, Minerals, Energy, and Geophysics Science Center