BERHAMPUR: Yaas, which made landfall 20 km south of Balasore on Wednesday, was the fifth such severe cyclone to hit the district in 130 years. Altogether 28 tropical cyclones made landfall in the northern district during the period. This was revealed in a study by Pratap Kumar Mohanty, professor of marine sciences, Berhampur University. “During the same period, 96 cyclones hit Odisha’s coast. Of these, twenty-three were severe cyclonic storms,” Mohanty, who studied the formations of cyclonic storms over the Bay of Bengal, said. Balasore was closely followed by Puri and Jagatsinghpur (20 each), Ganjam (13), Kendrapada (11) and Bhadrak (nine) as far as cyclones making landfall there during the period are concerned. About 541 tropical cyclones were formed over the Bay of Bengal in the last 130 years. Out of these, Mohanty said, the highest number of cyclones (126) was formed in November, followed by 94 in October, 64, including Yaas, in May and 52 in December. Though all cyclones did not make landfall in the state, their impact was felt on its vulnerable coast. Some of the cyclonic storms, which affected Odisha include Amphan in 2020, Titli in 2018 and Hudhud in 2014, among others. Mohanty said there are two peaks of tropical cyclones in the Bay of Bengal. While the primary peak is from October to December, the secondary one is from April to June. “During the pre-monsoon period that lasts from April to May and the post-monsoon season from October to December, cyclones with maximum sustained surface wind speed (MSW) of 34 knots or more take place in the northern Indian Ocean. The disturbances developed during the pre-monsoon season have higher probabilities of attaining the intensity of a severe cyclonic storm (SCS) compared to that of the post-monsoon period,” he said. Fani, Amphan and Yaas are appropriate examples of pre-monsoon cyclones of high intensity. Mohanty said there has been a significant reduction in the annual frequency of tropical cyclones over the northern Indian Ocean since the middle of the 20th century (1951-2018). In contrast, the frequency of very severe cyclonic storms during the post-monsoon period has increased significantly in the last two decades, he added.