Abstract

Tropical cyclones (TCs) of varying intensities have historically impacted the eastern United States. One of the resulting effects of TCs is often extreme precipitation, which was defined in this project as more than 20mm of precipitation per 6-hour period. Extreme precipitation events can lead to... Show moreTropical cyclones (TCs) of varying intensities have historically impacted the eastern United States. One of the resulting effects of TCs is often extreme precipitation, which was defined in this project as more than 20mm of precipitation per 6-hour period. Extreme precipitation events can lead to devastating impacts such as flooding, mudslides, and numerous human fatalities. Emergency managers, stakeholders, and the general public rely on impact-based information and guidance to prepare for impacts of TCs on human life, property, businesses, and the environment in both the present and for the future. A three-member ensemble of high-resolution (25km) of the Community Earth System Model (CESM) version 1 experiments from both present and future scenarios was used to investigate impacts on U.S. cities relevant to the aforementioned populations. Point-wise data from 17 eastern U.S. cities historically impacted by TCs were used to explore seasonality, regionality and future changes in the proportion of TC-generated precipitation and how extreme precipitation events change over time. The analyses showed that for most cities, the proportion of precipitation generated from tropical cyclones decreases in the future, but when filtering the data for extreme events, some cities saw increases in TC-generated precipitation for large rainfall rates. Looking at the data on a regional scale, it was found that the ratio of high-intensity TC-generated precipitation in inland cities increased in the future, whereas in coastal cities it decreased. Show less