Improving Simulations of Coastal Storm Surge
Better storm surge prediction capabilities could reduce the impacts of extreme weather events such as hurricanes.
Storm surge simulations are sensitive to tropical cyclone winds. A recent study assessed the feasibility of modeling storm surge using regional simulations of hurricane winds and pressure.
Reducing uncertainty in modeling tropical cyclones may advance more skillful prediction of storm surge, enabling the evaluation of coastal inundation risk in a warming climate.
Simulating tropical cyclone winds is challenging because they are sensitive to moist atmospheric processes, which are notoriously difficult to capture using models that parameterize cloud microphysical processes and convection. In a recent study, researchers evaluated the uncertainty in simulating hurricane wind and pressure as simulated by a regional model. To gain insights on modeling uncertainty, they evaluated an ensemble of regional simulations with different representations of clouds and convection for Hurricane Katrina using observed data. They used simulated winds and pressure in a storm surge model to simulate storm surge in the northern Gulf of Mexico. Then, they evaluated the storm surge simulations using high-water marks collected by the Federal Emergency Management Agency along the Alabama, Mississippi, and Louisiana coasts. Results showed that regional simulations of Hurricane Katrina are sensitive to parameterizations of both convection and cloud microphysical processes, which are linked to hurricane development and intensification. With the most skillful simulation of hurricane winds and pressure from the ensemble of simulations, error statistics of the storm surge simulations were comparable to storm surge simulations driven by observed winds and pressure. This finding demonstrates the feasibility of simulating storm surge and inundation using regional simulations of hurricane winds and pressure and a storm surge model to analyze climate change effects on coastal inundation.
Pacific Northwest National Laboratory
This study was funded by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research as part of the Integrated Assessment Research program.
Yang, Z., S. Taraphdar, T. Wang, L. R. Leung, and M. Grear. 2016. “Uncertainty and Feasibility of Dynamical Downscaling for Modeling Tropical Cyclones for Storm Surge Simulation,” Natural Hazards 84(2), 1161-84. DOI: 10.1007/s11069-016-2482-y.