An Analysis of Environmental Dynamical Control of Tropical Cyclone Intensity over the Bay of Bengal during 1981-2010 - Monitoring and Prediction of Tropical Cyclones in the Indian Ocean and Climate Change - page 85

negative gradient. The analysis also reveals that few TCs further intensified
when the large-scale environmental vertical wind shear was equal or greater
than 20 ms -1 , showing TCs can survive in quite strong vertical shears over the
Bay of Bengal. The inter-seasonal variability shows cyclones in the pre-
monsoon season tend to reach a larger fraction of their MI than in the post-
monsoon and lowest in the monsoon season.
Acknowledgements
The authors are grateful to the Director General of Meteorology, India
Meteorological Department, for his encouragement to carry out this study. The
authors would like to acknowledge JTWC, ECMWF and NCEP for providing
cyclone and model analysis data.
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