Influence of ENSO on Tropical Cyclones in North Atlantic in a high-resolution climate model:

• Other Authors: Finlayson, Marjahn Danielle (Marjahn Danielle Finlayson) (Author), (Suzanne O'Connell) (Thesis advisor), (author), () (Committee member), (Degree grantor)
• Format: Thesis
• Language: English
• Subjects: > -; North Atlantic
• Online Access: https://doi.org/10.14418/wes01.1.1176; https://digitalcollections.wesleyan.edu/islandora/object/ir%3A707/datastream/TN/view/Influence%20of%20ENSO%20on%20Tropical%20Cyclones%20in%20North%20Atlantic%20in%20a%20high-resolution%20climate%20model.jpg; https://digitalcollections.wesleyan.edu/object/ir-707

The tropical cyclones in the North Atlantic are known to cause intense damage and loss of property over United States. Thus, it is important for coupled climate models to simulate and predict the tropical cyclones. It is widely known that the El Niño-Southern Oscillation (ENSO) affects the tropical cyclone activity in the North Atlantic. In this study, the ability of the coupled climate model, the flux-adjusted version of Geophysical Fluid Dynamics Laboratory’s Forecast Oriented Low Ocean Resolution model, FLOR-FA, to simulate the relationship between ENSO and tropical cyclone activity in the North Atlantic in general and in the sub-basins is explored. FLOR-FA model successfully simulates the observed teleconnection between ENSO and tropical cyclones with reduced activity during El Niño and enhanced activity during La Niña in the North Atlantic. The model also captures the effect of ENSO on the environmental factors important for ENSO and the tropical cyclone relationship such as sea surface temperature, vertical wind shear, relative humidity and rainfall consistent with observations. During El Niño, the model simulates strong vertical wind shear, low relative humidity and reduced intensity of rainfall that creates unfavorable conditions for tropical cyclone activity. Further, weak vertical wind shear, high relative humidity and increased intensity of rainfall is simulated during La Niña leading to favorable conditions for the tropical cyclone activity. Despite some of the model’s inconsistencies compared to observations, the FLOR-FA model has better simulation of tropical cyclones and factors that affect tropical cyclone development, and therefore will aid in better prediction of the tropical cyclone occurrences in the North Atlantic. 2015 Old URL: https://wesscholar.wesleyan.edu/etd_hon_theses/1469 In Copyright – Non-Commercial Use Permitted (InC-NC)