Monitoring and forecasting of tropical cyclones over north Indian ocean

Abstract

Tropical cyclones (TCs) are the most devastating phenomena among all natural disasters, having taken more than half a million lives all over the world in the last five decades. TCs are accompanied by very strong winds, torrential rains and storm surges. The havoc caused by TCs to shipping in the high seas and coastal habitats along the Indian coasts due to above mentioned adverse weather have been known since hundreds of years. The tropical warm north Indian Ocean (NIO), like the tropical North Atlantic, the South Pacific and the NW Pacific, is a breeding ground for the disastrous TC phenomenon. Historically, in terms of loss to human life, the Bay of Bengal TCs have accounted for deaths ranging from a thousand to three hundred thousands. The Bay of Bengal has experienced more than 75% of the total world-wide TCs causing human death of 5000 or more in last 300 years (Dube et al., 2013). For example, the death toll had exceeded 3,00,000 and 1,40,000 in earlier Bangladesh severe cyclones of 1970 and 1991 respectively in which the damages were beyond imagination. Orissa Super Cyclonic Storm (SuCS) of 29-30 October 1999 had caused over 10,000 human deaths and resulted in destruction and damage to over 1.9 million houses in 14 districts of Odisha (Kalsi, 2006; Mohapatra et al., 2002). Recently there was death toll of 1,40,000 in Myanmar due to very severe cyclonic storm, Nargis during April-May, 2008 (Tyagi et al., 2010). There are several such examples of the enormous storm-havoc along not only the Eastern Indian coast but also along the coasts of the other rim countries of Bay of Bengal and Arabian Sea. The district-wise TC hazard proneness for India has been analysed by Mohapatra et al. (2012a). It indicates that entire east and west coast of India are prone to TC activity. However, TC proneness varies from district to district, being maximum along West Bengal and north Odisha coastal districts.