On The Role Of Pacific-atlantic Sst Contrast And Associated Caribbean Sea Convection In August-october Us Regional Rainfall Variability

• Published in: Geophysical Research Letters
• Other Authors: Kim, Dongmin (author), Lee, Sang-Ki (author), Lopez, Hosmay (author), Foltz, Gregory R. (author), Misra, Vasubandhu (author), Kumar, Arun (author)
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2020
• Subjects: Pacific; North Atlantic
• Online Access: https://doi.org/10.1029/2020GL087736; https://diginole.lib.fsu.edu/islandora/object/fsu%3A774314/datastream/TN/view/On%20The%20Role%20Of%20Pacific-atlantic%20Sst%20Contrast%20And%20Associated%20Caribbean%20Sea%20Convection%20In%20August-october%20Us%20Regional%20Rainfall%20Variability.jpg

This study investigates the large-scale atmospheric processes that lead to U.S. precipitation variability in late summer to midfall (August-October; ASO) and shows that the well-recognized relationship between North Atlantic Subtropical High and U.S. precipitation in peak summer (June-August) significantly weakens in ASO. The working hypothesis derived from our analysis is that in ASO convective activity in the Caribbean Sea, modulated by the tropical Pacific-Atlantic sea surface temperature (SST) anomaly contrast, directly influences the North American Low-Level Jet and thus U.S. precipitation east of the Rockies, through a Gill-type response. This hypothesis derived from observations is strongly supported by a long-term climate model simulation and by a linear baroclinic atmospheric model with prescribed diabatic forcings in the Caribbean Sea. This study integrates key findings from previous studies and advances a consistent physical rationale that links the Pacific-Atlantic SST anomaly contrast, Caribbean Sea convective activity, and U.S. rainfall in ASO. united-states, precipitation, Atlantic Warm pool, Caribbean Sea, el-nino, enso, multidecadal oscillation, north-american, Pacific-Atlantic SST interaction, s, summer rainfall, surface temperature, tropical atlantic, u, warm pool The publisher's version of record is availible at https://doi.org/10.1029/2020GL087736