This research is directed toward an improved understanding of key processes within the North American Monsoon System based on analyses of sounding data from the 2004 North American Monsoon Experiment (NAME).
The objective of the research is to extend and expand initial investigations of NAME data to (1) improve the quality of the NAME sounding data archive by (a) adding pibal, surface, and research aircraft observations to the gridded analysis, and (b) correcting humidity sensor errors and subsequently incorporate those corrections into the sounding data archive and gridded analyses; and (2) conduct diagnostic studies of monsoon processes over the NAME domain using the improved gridded analysis fields.
The intellectual merit of the research derives from the new understanding it will provide of the structural characteristics and physical processes associated with important North American monsoon phenomena. Among these are primary moisture sources for monsoon precipitation, jets and surges along the Gulf of California, tropical and midlatitude wave disturbances affecting the monsoon region, the diurnal cycle of convection, and heating and moistening of the atmosphere by deep convection. The NAME sounding dataset is unprecedented in its spatial and temporal resolution for this region, and therefore provides an opportunity for investigation of these phenomena with a detail heretofore not possible. The gridded analyses to be used to conduct these studies are independent of model data and consequently important diagnostic fields like divergence and vertical motion are not influenced by model parameterizations.
The broader impacts of the research relate to how it will improve understanding and ultimately prediction of the North American monsoon system. The operational sounding network over Mexico both prior to and after the NAME field phase is very sparse, which limits its utility in documenting monsoon phenomena. NAME was a short, but important period of enhanced observations (among which soundings are only one component), and it should be fully exploited to provide new insights on monsoon processes. The effort to further improve the quality of the sounding data is important because this dataset will be made available to and be used by diagnosticians and the modeling community for many years to come as a source of analysis and validation in a tropical, coastal mountainous environment that is typical of other coastal regions where much of the world's heaviest precipitation occurs.
