Bimodal Character of Cyclone Climatology in the Bay of Bengal Modulated by Monsoon Seasonal Cycle*

Zhi Li, Weidong Yu, Tim Li, V. S. N. Murty, Fredolin Tangang
2013 Journal of Climate  
2012: Bimodal character of cyclone climatology in Bay of Bengal modulated by monsoon seasonal cycle. J. Climate. Abstract 1 The annual cycle of tropical cyclone (TC) frequency over the Bay of Bengal (BoB) 2 exhibits a notable bimodal character, different from a single peak in other basins. The 3 causes of this peculiar feature were investigated through the diagnosis of a genesis 4 potential index (GPI) with the use of the NCEP reanalysis I dataset during the period 5 1981-2009. A methodology
more » ... 9. A methodology was developed to quantitatively assess the relative 6 contributions of four environmental parameters. Different from a conventional view 7 that the seasonal change of vertical shear causes the bimodal feature, we found that 8 the strengthened vertical shear alone from boreal spring to summer cannot overcome 9 the relative humidity effect. It is the combined effect of vertical shear, vorticity and 10
doi:10.1175/jcli-d-11-00627.1 fatcat:orl2ydhgrre6php62xocy2m5ia