Suchit Basineni

El Niño–Southern Oscillation and Atlantic Multi-decadal Oscillation Impact on Hurricanes in the North Atlantic Basin

Started Apr. 2, 2024

Abstract or project description

Tropical cyclones (TCs), including hurricanes and typhoons, cause significant property damage and loss of life, making it crucial to understand the factors driving extreme TCs. The El Niño–Southern Oscillation (ENSO) influences TC activity through tropospheric vorticity, wind-shear, and atmospheric circulations. Apart from atmospheric changes, oceans influence activity through sea surface temperatures (SSTs) and deep ocean heat content. These Atlantic SSTs determine the Atlantic Multi-decadal Oscillation (AMO), which indicates SST variability in the Atlantic. This research focuses on ENSO, AMO, and SST’s impact on the intensity and frequency of TCs in the North Atlantic Basin. AMO and SST anomalies are increasing at an alarming rate, but it remains unclear how their dynamics will influence future TC behavior. I used observational cyclone track data from 1950-2023, the Oceanic Niño Index (ONI), and NOAA’s Extended Reconstructed SST V5 (ERSST). I found that Increasing SSTs over the past decade indicate stronger TCs, while warm-phase AMO periods correspond with higher TC frequency. Meanwhile, a greater frequency of landfalling TCs can be attributed to La Niña or ENSO-neutral, with El Niño decreasing the frequency of landfalling TCs. Such relationships suggest that as the seasonal predictability of ENSO and SSTs improve, seasonal TC forecasts may improve.