Quantifying tropical cyclone rainfall from weather to climate scales in numerical simulations and observations (Invited)

Monday, December 9, 2019 - 10:20
Add to Calendar

The use of climate models at high horizontal resolutions (i.e., grid spacing less than 30 km) has become routine over the last decade. Such models at both global and regional scales have been used to study the large-scale controls of tropical cyclone (TC) intensity and frequency in past, present and future climate. The main focus of this work is to better quantify and understand the rainfall and extreme precipitation associated with TCs as they interact with coastlines. In particular, this study uses various configurations of the Community Atmosphere Model version 5 (CAM5), a comprehensive atmospheric general circulation model, forced with prescribed sea-surface temperatures (SSTs) and greenhouse gases for past, present and future climate. The model is configured with both global and variable-resolution grid configurations (focusing on the North Atlantic region) with horizontal grid spacing of approximately 28 km to explore TC rainfall from weekly to decadal time scales. These CAM5 simulations are compared to various estimates of observed rainfall at these temporal scales using satellite, gauge and merged rainfall datasets and gridded reanalysis products. The TempestExtremes software has been modified to calculate storm size and extract TC relative rainfall in the CAM5 simulations and in observations. These present climate CAM5 simulations are then compared to past and future climate simulations to investigate potential changes in TC rainfall characteristics. This work integrates with the larger community effort to understand flooding hazards within TCs and how these hazards might be altered in the coming decades.

Link for More Information: