92nd American Meteorological Society Annual Meeting (January 22-26, 2012)

Wednesday, 25 January 2012
The Brown Ocean Concept: A Spatio-Temporal and Theoretical Analysis of Intensifying Tropical Cyclones Over Land
Hall E (New Orleans Convention Center )
Theresa Andersen, Univ. of Georgia, Athens, GA; and J. M. Shepherd

The IPCC has indicated the global water cycle may accelerate due to current climate change and have an impact on the frequency and intensity of tropical cyclones. Studies have shown that soil moisture conditions can create soil moisture memory that affect future convective activity and may play a role in landfalling tropical cyclone re-intensification. This has been termed the "brown ocean" because moisture from the ocean is typically the primary source for the energetics driving tropical systems. The proposed research aims to first address the global spatio-temporal characteristics of landfalling tropical cyclone re-intensifications and quantify the associated dynamical, geographical, and/or topographical factors. Events that qualify as re-intensified will be analyzed for attributes such as location, size and intensity, duration of re-intensification, and path. Data will be be extracted from MERRA, GLDAS, and NCAR/NCEP Reanalysis Project to assist in differentiating re-intensification from mid-latitude transition. The second objective is to compare extratropical transition versus re-intensification of tropical storms in terms of environmental conditions, strength of storm, and potential damage. A literature review and results from objective 1 will provide an overview of the respective environmental characteristics of re-intensifying cyclones and extratropical transitioning cyclones over land. The third objective is to use HYDRUS-1D to model surface fluxes and WRF-LIS to analyze a landfalling tropical cyclone with emphasis on soil moisture interactions, flux magnitudes, and storm evolution compared to a tropical cyclone over the ocean.

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