Seminar Title
Impact of sub-seasonal and quasi-biweekly oscillations on tropical cyclones over the Bay of Bengal
Seminar Type
Progress Seminar
Earth and Atmospheric Sciences
Speaker Name
Gorja Mohan Murali Krishna ( Rollno : 520er1001)
Speaker Type
Mining department seminar hall
Date & Time
12 Jun 2023 10:00 AM
Prof. Naresh Krishna Vissa

Accurate estimation of Tropical cyclone (TCs) movement (track) is of utmost importance among TCs-related metrics because the forecasts of intensity or rainfall become absurd if the predicted track is incorrect. In this study, we analysed the influence of prevailing atmospheric oscillations at different scales on the movement of TCs over the Bay of Bengal (BoB). The study analysis uses the best-track dataset for TCs available from IMD during 1982-2020 and global ERA5 reanalysis. Out of these two, the ERA5 dataset consists of single and multi-level variables to extract and examine the composites of outgoing longwave radiation, low-level vorticity, vertically integrated steering flows, and moisture fluxes over the BoB. The composite features analysed at multi-scales suggest that the pre-monsoon TCs track is predominantly determined by the anomalies associated with the quasi-biweekly oscillations (QBWO) and intra-seasonal oscillations (ISO). Whereas, during post-monsoon, the prevailing mean climatology environment is critical in governing the storm track. Similarly, the study also signifies that QBWO and ISO-induced anomalies jointly provide a guiding effect for TCs moving northward, north-eastward, north-westward and TCs taking re-curvature paths. Whereas the climatological mean fields mainly drive the westward-moving TCs. However, our analysis of the examined anomalies on the inter-annual scale does not exhibit any significant physical linkages with the movement of TCs.