Climate Change in Tropical Cyclones and Monsoon Depressions of North Indian Ocean - Monitoring and Prediction of Tropical Cyclones in the Indian Ocean and Climate Change - page 37

there is little climate change in the Intensification Index of the cyclones of
north Indian Ocean due to global warming.
6. Conclusions
Annual MD frequency of the 119 years (1891-2009) has a large decreasing
trend. This is possibly related to the observed rapid warming of the equatorial
Indian Ocean and the consequent weakening of the monsoon Hadley circulation
and LLJ. The first half of the period studied had only feeble increase in SST
and the decrease in MD frequency was also feeble. Both MD and TC have
prominent decadal oscillation of period about forty years with the same temporal
phase. During the period studied there were three FDO cycles. The FDO in TC
of October to December season is found to be associated with decadal changes
in equatorial winds over the SST of NIO. Although it has been shown that
there is increasing trend in the frequency of severe cyclones during the 119-
year data available, we suggest that this may be due to better monitoring
capability of the intensity of cyclones in the period since 1965 due to satellite
observations.
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