CHENNAI: The severe cyclonic storm Gaja that hit the Tamil Nadu coast in November last year was the second strongest and first-ever rare looping track cyclone formed over the Bay of Bengal after 1996. No wonder, the storm has wrecked havoc leaving 53 people dead and uprooting lakhs of trees.
A detailed report, published by the Regional Specialised Meteorological Centre (Tropical Cyclones) of Indian Meteorological Department (IMD), reveals that Gaja’s peak maximum sustained surface wind speed was 130 kmph gusting to 145 kmph. This is much higher than official initial estimates. Even the government order from the Department of Revenue and Disaster Management issued on December 10 declaring districts of Nagapattinam, Tiruvarur, Thanjavur, Pudukkottai and Dindigul as cyclone-affected said cyclonic winds were gusting upto 110 kmph.
When compared, in terms of the maximum sustained winds at the time of cyclone crossing the Tamil Nadu coast in last 30 years since 1990, Gaja ranks third only after the Karaikkal cyclone in 1993 and the cyclone Thane in 2011, where wind speeds recorded 167 kmph and 140 kmph respectively. Gaja leaves behind Cyclone Vardah in 2016, which clocks winds’ speed of 122 kmph and wiped off green cover in Chennai.
The report said Gaja was the sixth cyclone over north Indian Ocean during 2018 against the normal frequency of about 4.5 cyclones per year during the satellite era (1961 onwards). It was the first ever looping track cyclone over the Bay of Bengal after 1996 and the system has one of the longest track lengths equal to 3,418 km. “Despite unfavourable environmental conditions, the system intensified into a very severe cyclonic system (VSCS) just prior to landfall near to coast,” IMD officials said and added that VSCS intensity of the system was short-lived (about three hours).
Weather blogger Pradeep John said that since 1842, only six cyclones hav looped, including Gaja, making it a rare occurrence. “When the storm gets caught between two ridges in the open sea, the system loop tracks.”