Seminar: Dr. Christina Patricola, Texas A&M

“Oceanic and Atmospheric Controls on Tropical Cyclone Activity” Tropical cyclones are among the costliest and deadliest natural hazards. Climate variability and change influence the global large-scale climate, leading to changes in tropical cyclone frequency, intensity, and landfall rate. In order to improve predictability on weather to climate timescales and to build resilient coastal communities, it is necessary to understand the physical relationships between tropical cyclones and large-scale climate in observations and climate models capable of resolving tropical cyclones. One major source of seasonal tropical cyclone predictability is upper ocean temperature patterns, which can be predictable in advance of the hurricane season and can influence environmental favorability for tropical cyclones. I will discuss the compensating and constructive influences of Atlantic and Pacific sea-surface temperature patterns on tropical cyclones, as well as the mechanisms by which the location and intensity of tropical Pacific warming during El Niño impact tropical cyclones. In addition, the roles of atmospheric tropical easterly waves and atmospheric internal variability in seasonal tropical cyclone variability will be discussed. Furthermore, reliable future projections of tropical cyclone activity depend on our coupled atmosphere-ocean climate modeling capability. Systematic climate model biases are found to hinder representation of tropical cyclones in the coupled system, pointing to needed improvements in the representation of specific physical processes in models.