Analysis of extreme precipitation and cyclogenesis at the weather-climate interface

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Weather extremes in the form of heavy precipitation, long-duration ice storms, and rapid cyclogenesis can have especially significant consequences in the form of human injuries and fatalities, flooding, coastal erosion and property losses. There is a consensus among scientists that a warming climate is responsible for recent increases in such extremes, particularly precipitation.***The long-term objective of my research program is to enhance our understanding and forecasting of persistent weather extremes that often contribute to the sub-seasonal climate state. The relatively long time periods of these weather extremes typically exceed the typical limit of a weather forecast's predictability, towards a time range in which the future atmospheric state can only be predicted statistically. This extended time scale, ranging from 10 days to one month is defined to be the “weather-climate interface” time scale. Persistent weather regimes enhance the durations of precipitation and dry conditions, and thus increase the chances of heavy precipitation and droughts. An improved understanding of these extremes will benefit academic researchers with a needed synthesis and collaboration of weather and climate scientists.***The most immediate shorter-term objectives of this research proposal include comprehensive analyses of extreme precipitation and cyclogenesis from a weather-climate intersection perspective. Implicit in these shorter-term objectives is the assumption that precipitation, and cyclogenesis, are key processes to analyze in our pursuit of understanding persistent weather and its intra-seasonal variability.***My research focuses on analyses of fundamental thermodynamic and dynamic principles as foundations for defining environments that facilitate the developments of extreme precipitation, including freezing rain, and cyclogenesis. This research includes analyses of air masses, synoptic-scale forcing, static stability, the dynamic tropopause jet stream, and maximum baroclinic growth rates. These metrics provide the necessary environmental conditions for precipitation and cyclogenesis, and also serve as validation tools for both weather- and climate-models. Furthermore, these environmental metrics are readily computed from the relatively coarse-resolution global reanalyses.***Subsequent analyses of feedbacks, both negative and positive, of these synoptic- and meso-scale processes onto the planetary-scale environments will provide insight into the complex set of interactions among cyclogenesis, precipitation, and the environment that either encourages or discourages their existence.**