Authors: Joshua Bregy*, Indiana University, Justin Maxwell, Indiana University, Scott Robeson, Indiana University
Topics: Climatology and Meteorology, Earth Science, Hazards, Risks, and Disasters
Keywords: tropical cyclones, precipitation, climatology, teleconnections, climate, NASH, North Atlantic, hurricanes
Session Type: Paper
Start / End Time: 5:20 PM / 7:00 PM
Room: Grand Couteau, Sheraton, 5th Floor
Presentation File: No File Uploaded
Tropical cyclone precipitation (TCP) can cause severe inland flooding, initiate slope failure, and create large sinkholes. Previous studies show that TCP contributes substantially to seasonal precipitation budgets in the eastern United States. However, present knowledge of TCP climatology remains limited by the spatial coverage of weather stations. Here we develop a new high-resolution (0.25°x0.25°) TCP climatology using HURDAT2 and CPC US Unified Precipitation data (1948–2015). From June to November (JJASON; 1948–2015), the maximum total TCP is ~2200–3800 mm along the coast, and decreases inland. Spatial patterns of TCP contribution to total JJASON precipitation largely mirror total TCP, with maxima (6–8%) occurring along coastal Texas and North Carolina. Similar spatial patterns are seen in the mean JJASON TCP and mean TCP contribution over the study period, with maxima extending beyond coastal Texas and North Carolina. JJASON TCP (total, mean, and contribution) was correlated with mean JJASON values for the Bermuda High Index (BHI), ENSO–BEST, and NAO, to examine the degree to which these phenomena influence spatiotemporal changes in TCP. Of the three indices, BHI had the strongest and most spatially consistent correlation with TCP, with significant correlations occurring in the interior of the southeast. These results indicate a strong regional relationship between TCP distribution and the Bermuda High (BH). TCP distribution depends on TC track direction, and is therefore connected to the BH, which steers TCs. Our derived high-resolution TCP climatology furthers our understanding of TC–climate interactions and hazards associated with TCs, serving as an invaluable tool in hazard mitigation efforts.