Response of upper ocean and impact of barrier layer on Sidr cyclone induced sea surface cooling
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In the present study an attempt has been made to investigate the impact of salinity stratification on the SST during the tropical cyclone (TC) passage. In this context, a severe post monsoon cyclone, Sidr, (Category 4) that developed over the south-eastern Bay of Bengal (BoB) during 11–16 November, 2007 was chosen as a case study. Pre-existence of a thick barrier layer (BL), temperature inversions and a higher effective oceanic layer for cyclogenesis (EOLC) were noticed along the path of the Sidr cyclone. The analysis of available Argo floats along the Sidr cyclone track also revealed less cooling during as well as after its passage as was reported from satellite derived SST. The role of BL on Sidr induced sea surface cooling was investigated using a diagnostic mixed layer model. Model results also depict the reduced sea surface cooling during the passage of Sidr. This is attributed to the presence of BL which results in the inhibition of the entrainment of cool thermocline water into the shallow mixed layer. Climatological as well as in situ observations of tropical cyclone heat potential (TCHP) and EOLC shows that the Sidr cyclone propagated towards the regions of higher EOLC.
Key wordssalinity stratification mixed layer depth temperature inversions barrier layer tropical cyclone
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- Black PG (1983) Ocean temperature change induced by tropical cyclones. Ph.D. Thesis, The Pennsylvania State University, 278 pGoogle Scholar
- Emanuel KA(1986) An air-sea interaction theory for tropical cyclone. Part I. Steady-state maintenance. J Atmos Sci 43:585–604Google Scholar
- Jacob SD, Shay LK, Mariano AJ (2000) The 3D oceanic mixed layer response to Hurricane Gilbert. J Phys Oceanogr 14:59–78Google Scholar
- Murty VSN, Sarma MSS, Tilvi V (2000) Seasonal cyclogenesis and the role of near-surface stratified layer in the Bay of Bengal. In: Proceedings of PORSEC 2000 (A-092), NIO, Goa, India, 5–8 Dec, pp 453–457Google Scholar
- Murty VSN, Sarma MSS, Jenson GV, Vidya PJ (2008) Impact of freshwater influx on the cyclogenesis, tracks of cyclones and air-sea coupling over the Bay of Bengal. In: Proceedings volume of Workshop on Natural Hazards and Coastal Processes of Indian Coast (NHACPIC-2008), 30 April, pp 54–63Google Scholar
- Prasad KB, Barman R, Dube SK, Pandey PC, Ravichandran M, Nayak S (2009) Development of a new comprehensive ocean atlas for Indian Ocean utilizing Argo data. Int J Climatol 30:185–196Google Scholar
- Price JF (1983) Internal wave wake of a moving storm. Part I. Scales, energy budget, and observations. J Phys Oceanogr 13:949–965Google Scholar
- Vissa NK, Satyanarayana ANV, Prasad KB (2012b) Comparison of Mixed Layer Depth and Barrier Layer Thickness for the Indian Ocean using two different Climatologies. Int J Climatol. doi:10.1002/joc.3635Google Scholar
- Vissa NK, Satyanarayana ANV, Prasad KB (2013c) Impact of South China Sea cold surges and PEIPAH typhoon in initiating Sidr cyclone in the Bay of Bengal. Pure Appl Geophys. doi:10.1007/s00024-013-0671-0Google Scholar