Relationship between Tropical Atlantic sea surface temperature variability and southern Indian Ocean tropical cyclones
Abstract
Recent studies have found that tropical Atlantic sea surface temperature (SST) variability may be influencing tropical Indian Ocean climate. Due to the economic and social impact of tropical cyclones, it is important to investigate how an Atlantic-Indian Ocean connection may be affecting tropical cyclone behavior in the southern Indian Ocean. In this study, the International Best Track Archive for Climate Stewardship (IBTrAC) tropical cyclone database is used to derive metrics of tropical cyclone behavior, which are then compared with an index of tropical Atlantic SST variability. Changes in tropical Atlantic SSTs are found to coincide with significant differences in tropical cyclone activity for portions of the southern Indian Ocean. In addition, for these same regions, tropical Atlantic SST variability is associated with changes in large-scale atmospheric conditions, including wind shear, low-level vorticity, and humidity, typically associated with tropical cyclogenesis. These findings indicate a possible link between tropical Atlantic conditions and cyclone activity in the Indian Ocean mediated through a teleconnection between tropical Atlantic SSTs and large scale atmospheric conditions over the southern Indian Ocean. The nature of this teleconnection and the mechanisms driving it are being further explored with model experiments.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2011
- Bibcode:
- 2011AGUFM.A11G0175D
- Keywords:
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- 3339 ATMOSPHERIC PROCESSES / Ocean/atmosphere interactions;
- 3372 ATMOSPHERIC PROCESSES / Tropical cyclones;
- 3373 ATMOSPHERIC PROCESSES / Tropical dynamics