TY - JOUR
T1 - The impact of sea surface temperature on the North American monsoon
T2 - A GCM study
AU - Yang, Zong Liang
AU - Gochis, Dave
AU - Shuttleworth, W. James
AU - Niu, Guo Yue
PY - 2003/1/15
Y1 - 2003/1/15
N2 - The NCAR CCM3 was used to simulate the circulation and rainfall patterns of the North American monsoon system (NAMS). When forced with repeated annual cycles of climatological average sea surface temperatures (SSTs), the CCM3 significantly under-represents monsoon rainfall in the southwest United States while simulating excessive precipitation in the tropical eastern Pacific Ocean and the Caribbean Sea. However, when forced with the observed monthly average SSTs from 1979 to 1997, the CCM3 produces an improved simulation of monsoon rainfall in the southwestern U.S., as well as in the eastern tropical Pacific Ocean and the Caribbean Sea. Using the SSTs for 1983 in the Pacific and climatological SSTs elsewhere, the modeled circulation and rainfall distribution resembles that given with observed monthly average SSTs. The simulations are sensitive to the size of the domains over which the Pacific SST anomalies are imposed. Overall, these results suggest that the magnitude and size of winter- and springtime Pacific SST anomalies have a significant influence on summertime rainfall in the southwest U.S., and that these SSTs contribute to the NAMS precipitation climatology in extreme years more than in less extreme years.
AB - The NCAR CCM3 was used to simulate the circulation and rainfall patterns of the North American monsoon system (NAMS). When forced with repeated annual cycles of climatological average sea surface temperatures (SSTs), the CCM3 significantly under-represents monsoon rainfall in the southwest United States while simulating excessive precipitation in the tropical eastern Pacific Ocean and the Caribbean Sea. However, when forced with the observed monthly average SSTs from 1979 to 1997, the CCM3 produces an improved simulation of monsoon rainfall in the southwestern U.S., as well as in the eastern tropical Pacific Ocean and the Caribbean Sea. Using the SSTs for 1983 in the Pacific and climatological SSTs elsewhere, the modeled circulation and rainfall distribution resembles that given with observed monthly average SSTs. The simulations are sensitive to the size of the domains over which the Pacific SST anomalies are imposed. Overall, these results suggest that the magnitude and size of winter- and springtime Pacific SST anomalies have a significant influence on summertime rainfall in the southwest U.S., and that these SSTs contribute to the NAMS precipitation climatology in extreme years more than in less extreme years.
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U2 - 10.1029/2002GL015628
DO - 10.1029/2002GL015628
M3 - Article
AN - SCOPUS:0038266421
SN - 0094-8276
VL - 30
SP - 5-1 - 5-4
JO - Geophysical Research Letters
JF - Geophysical Research Letters
IS - 2
ER -