Hydrodynamic Modelling of Storm Surge with Modified Wind Fields along the East Coast of India

Abstract

Propagation of tropical cyclones and their landfall along the coast affect the livelihood of the coastal community with loss of life, and Bay of Bengal is particularly vulnerable as past disasters have shown. The present study investigates the effects of tropical cyclones namely Phailin, Hudhud and Vardah during its landfall along the East Coast of India. Numerical modelling of storm surges primarily depends on the wind characteristics, for which, the performance of the simulated storm surge from cyclone wind and pressure fields of ECMWF is examined with Telemac-2D. The quality of the wind field is enhanced by applying available wind modification techniques, such as the parametric cyclone wind model superposed with ECMWF wind field, and the direct modification of ECMWF wind field. The superposed wind speed is found in good agreement with the measured wind data. The hydrodynamic simulation was then performed for the cyclonic events for the computation of the storm surge. The predictions agree well with the observed surges for the simulations performed with modified wind fields. The error reduced from 15 cm to 6 cm and model skill improved by 3% leading to a correlation coefficient of 0.98.

Keywords:

• cyclone
• storm surge
• modified wind field
• statistical analysis

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work is supported by the Department of Science & Technology, India Grant No. DST/CCP/CoE/141/2018C under SPLICE – Climate Change Programme. Indian National Centre for Ocean Information Services (INCOIS) - Earth System Science Organization (ESSO), MoES, Govt. of India, is acknowledged for their data support.