Inhomogeneous influence of the Atlantic warm pool on United States precipitation

• Published in: Atmospheric Science Letters
• Main Authors: Liu, Hailong, Wang, Chunzai, Lee, Sang‐Ki, Enfield, David
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2014
• Subjects: North Atlantic
• Online Access: http://dx.doi.org/10.1002/asl2.521; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fasl2.521; https://rmets.onlinelibrary.wiley.com/doi/pdf/10.1002/asl2.521

Abstract On interannual time scales, the warming of the Atlantic warm pool ( AWP ) is associated with a tripole sea surface temperature ( SST ) pattern in the North Atlantic and leads to more rainfall in the central and eastern US . On decadal‐to‐multidecadal time scales, the AWP warming corresponds to a basin‐wide warming pattern and results in less precipitation in the central and eastern US . The inhomogeneous relationship between the AWP warming and US rainfall on different time scales is largely due to the sign of mid‐latitude SST anomaly. The negative mid‐latitude SST anomaly associated with the tripole pattern may enhance the low sea level pressure over the northeastern North American continent and also enhance the barotropic response there of the AWP ‐induced barotropic Rossby wave. This strengthened low pressure system, which is not exhibited when the warming is basin‐wide, results in a different moisture transport variation and thus the rainfall pattern over the United States.