Cyclones take 2019 by storm

India Meteorological Department data revealed that 2019 has broken a four-decade-old cyclone record, as the eighth cyclone over north Indian Ocean, called Pawan, crossed the Somalia coast on Saturday.

The North Indian Ocean last recorded 10 cyclones in 1893, 1926, 1930 and 1976. After 1976, the year 2019 has recorded the highest number of cyclones over the north Indian ocean.

Till November this year, seven cyclones over this region had brought 2019 at par with 2018 for the number of cyclones recorded during each of these years. With the recent cyclonic storm Pawan over the southwest Arabian Sea from December 2 till date, 2019 has broken last year’s cyclone record, as well as that of the last 40-plus years’.

The data revealed that 2019 has recorded development of more intense cyclones over the Arabian Sea. Out of five cyclones, there has been one cyclonic storm (Pawan), two very severe cyclonic storms (Vayu, Hikaa), one extremely severe cyclonic storm (Maha) and one super cyclonic storm (Kyarr).

After 1976 (when 10 cyclones had hit the North Indian Ocean), the maximum number of cyclones affecting the region was seven in 1985 and 2018. But till this December, 2019 exceeded this number as another cyclone, Pawan, came along — taking the total number of cyclones over the north Indian ocean to eight this year.

IMD director general Mrutyunjay Mohapatra said that the Arabian Sea cyclone season has been more active this year. “The reason being warmer sea surface temperature over the Arabian Sea, a positive Indian Ocean diapole that causes warming near Somalia and cooling near Indonesia, and Madden Julian Oscillation (which moves west to east). This increased the convective clouding. The oscillation has been favorable for the Arabian Sea this year. Formation of deep, tall clouds is a requirement for the development of cyclones,” he said.

Another reason is the active Northeast monsoon over the Indian region, which is helping moisture supply over the Arabian Sea up to the middle tropospheric level. “The seasonal rainfall for the country between October and December has been 33% above normal as on date,” he said.

As per IMD, 11 cyclonic disturbances have developed over the north Indian Ocean — four over the Bay of Bengal and seven over the Arabian Sea — during 2019 as against the normal of 12. T Cyclonic disturbances are those with maximum wind speed of 17 Knots or more, while cyclones have a maximum wind speed of 34 knots or more and severe cyclones have a maximum wind speed of 48 Knots or more.

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