INVITED TALK: Hydroclimatology Of The North American Monsoon: Bound By Terrain But Courted By ENSO?
Gochis, David J 1
1 National Center for Atmospheric Research
Research into the North American Monsoon reveals a continental-scale climatic system possessing marked intra- and inter-regional variations in hydroclimatology. Some works have elucidated the striking role that regional physiography (e.g. terrain and proximity to water bodies) within the monsoon domain has on creating regional precipitation climatologies. Analyses of seasonal precipitation in northwest Mexico, the southwest U.S. and the Great Plains regions reveal distinct modes of spatially coherent precipitation, which, in turn, point to subtleties in their respective precipitation processes. It is now clear that the North American Cordillera plays a key role defining hydroclimatic regions by controlling access to regional moisture sources and driving lower atmospheric circulations leading to convective precipitation. What is still unclear is how the climatological structure of precipitation features is linked to large-scale teleconnective features such as the El Nino/Southern Oscillation (ENSO) and/or other remote forcing mechanisms. This talk will provide an overview of the characteristics of several key precipitation regimes operating under the influence of the North American Monsoon and explore the local and remote atmospheric forcing mechanisms governing their behavior.