Quantifying the historical intensity and spatial extent of extreme tropical cyclone precipitation
Abstract
The intensity and spatial extent of tropical cyclone precipitation (TCP) can modify and exacerbate the impacts of landfalling storms. For example, heavy rainfall during 2017's Hurricane Harvey led to the concurrent occurrence of unprecedented precipitation across several Texas metropolitan areas. Harvey's rainfall intensity and vast footprint resulted in 89 fatalities and $127.5 billion in damages. To place this unprecedented hydroclimatic event in a historical context, this study harnesses long records of precipitation in the United States and Atlantic tropical cyclone tracks to investigate the climatological intensity and spatial extent of extreme TCP. We use GHCN-Daily station precipitation data and the HURDAT 2 database of best tropical cyclone tracks from 1900 to 2017, which include tropical depressions, tropical storms, and hurricanes. We first quantify extreme values of TCP along landfalling tropical cyclones tracks. Using these extreme TCP values as thresholds, we apply semivariogram and moving-neighborhood approaches to quantify the spatial extent, i.e., length scales, of extreme TCP. Preliminary results show significant differences in the intensity of extreme TCP among storm types. We also find that the length scales of extreme TCP vary among storm types. For example, using a threshold of 50 mm/day, we find that extreme TCP length scales along hurricane tracks are longest while those along tropical depression tracks are shortest. Further, we investigate temporal trends and variations in the intensity and spatial extent of extreme TCP over the 1900-2017 period, and explore the atmospheric and oceanic factors that control variations in intensity and spatial extent of extreme TCP. This study is a critical step for understanding the changing characteristics and impacts of extreme TCP in a warming climate.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFMGC13C..05T
- Keywords:
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- 1616 Climate variability;
- GLOBAL CHANGEDE: 1620 Climate dynamics;
- GLOBAL CHANGEDE: 1630 Impacts of global change;
- GLOBAL CHANGEDE: 4313 Extreme events;
- NATURAL HAZARDS