Evaluating Impacts of Landfalling Tropical Cyclones Using a Hybrid WRF Cyclone Model

The economic impacts of weather and climate extremes are rising, with tropical cyclones (TC) amongst the most devastating of these extreme weather events. Even minor hurricanes on the Saffir-Simpson Hurricane Wind Scale have resulted in catastrophic losses. As an example, Hurricane Ike, the third costliest USA hurricane on record, made landfall in Galveston and created storm surge of up to 15 feet, and immense damage, even though it was only a category two hurricane at landfall. Climate change and growing populations in hazard-prone areas will only exacerbate the impacts of extreme weather events.

While analyzing events such as Hurricane Ike enhances our understanding of historical hurricanes, it does not address the full range of potential societal and economic impacts if, for instance, Ike moved slower, was larger, or made landfall in a slightly different location. Along any 50-mile section of the Texas coast, landfalling hurricanes only occur approximately once ever 6 years¹.

To understand the broader range of possible hurricane scenarios, a new modeling framework based on the WRF Model has been developed. The Hybrid WRF Cyclone Model (HWCM) is a unique approach to simulating idealized cyclones in a real-world configuration using a full numerical model. It enables the simulation of large numbers of cyclones with different characteristics making landing in the same location. This presentation will address the development of the HWCM, and showcase the use of the model to study the impacts of Ike-like tropical cyclones under climate change and preindustrial conditions and compare these to observations.

¹Roth, D.M, 2012: Hydrometeorological Prediction Center. Texas Hurricane History. United States National Oceanic and Atmospheric Administration's National Weather Service.