The American Monsoon Systems

Robertson, Andrew W.; Mechoso, Carlos R.; Ropelewski, Chester F.; Grimm, Alice M.

This paper examines similarities and differences among major features of the North and South American monsoon systems. Over both North and South America the summertime circulation shows upper-level anticyclone/low-level heat low structures. These develop at different distances from the equator. It is argued that ascent to the east where convective and subtropical convergence zones develop, and subsidence over the cool waters of the eastern Pacific where stratocumulus decks provide a radiative heat sink to the tropical atmosphere are integral and unifying aspects of both monsoon systems. The intraseasonal and interannual variability of the systems are contrasted. The reported links between anomalies in soil conditions and sea surface temperatures are marginal, and consistently long-range predictability is low. Ropelewski et al. (2004) and Grimm et al. (2004) focus on each of the American monsoon systems in companion papers.

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Also Published In

The Global monsoon system : research and forecast : report of the International Committee of the Third International Workshop on Monsoons (IWM-III) 2-6 November 2004, Hangzhou, China
World Meteorological Organization

More About This Work

Academic Units
International Research Institute for Climate and Society
WMO/TD, 1266
Published Here
August 21, 2012