Simulation of Ocean Upper Layer Response to Moving Indian Ocean Cyclone Using Reduced Gravity Ocean Model

Abstract

The sensitivity of the ocean mixed layer response to different parameters such as model horizontal resolution, vertical temperature gradient and eye size is investigated in response to moving Indian Ocean cyclone. For this, a one and one-half layer wind-driven reduced-gravity ocean model is forced with synthetic cyclonic vortex. The sensitivity studies are carried out for a cyclone moving along idealized tracks, initially and then for three observed cyclones (TC 01A), (TC02B) and (TC04A) during 2004. Increasing model resolution resulted in stronger ocean response. The role of initial vertical temperature gradient in modulating the ocean response is found to be important.

Keywords:

• Indian Ocean cyclone
• reduced gravity model
• model resolution
• upwelling
• synthetic vortex
• right bias
• eye size
• vertical temperature gradient

Acknowledgements

Thanks are due to Brian Doty for the GrADs software, which is used for preparation of the diagram. The work is carried out on SUN workstation acquired under the project funded by DOD. The authors also thank the anonymous referees for their useful suggestions.