Influence of Climatic Oscillations on Indian Ocean Tropical Cyclone Energy

Abstract

Tropical Cyclones form in 4 independent regions of the Indian Ocean Basin ranging from the Arabian Sea, Bay of Bengal, Western South Indian, and Eastern South Indian Ocean. These cyclones lead to distinct patterns in their Accumulated Cyclone Energy for their particular region. The goal of this research article is to examine how the larger scale climate oscillations including ENSO, the Indian Ocean Dipole, and the Subtropical Indian Dipole of the Indian Ocean influence both the patterns in Tropical Cyclone Energy as well as the patterns in the large scale atmosphere of each of the aforementioned sub regions during high ACE events and lower ACE events. This analysis was done using linear regression techniques and appears to reveal the main influence on both ACE and the larger scale atmosphere of the basin is the phases, both warm (El Niño) and cold (La Niña), of the El Niño Southern Oscillation. This is especially true for the northern half of the basin with El Nino leading to higher shear, which is the main weather variable that has an impact on lowering ACE. The other Oscillations appear to have some impact through the placement of their warm pools in the southern portion of the region.