NHESSD Natural Hazards and Earth System Sciences Discussions NHESSD Nat. Hazards Earth Syst. Sci. Discuss. 2195-9269 Göttingen, Germany 10.5194/nhess-2017-66 Cyclonic intensity study using sea level pressure estimations from Ocensat-II scatterometer winds over Bay of Bengal during 2013 Purna Chand C. 1 Venkateswara Rao M. 1 Prasad K. V. S. R . 2 Rao K. H. 1 National Remote Sensing Centre, Hyderabad, India Dept. of Meteorology and Oceanography, Andhra University, Visakhapatnam, India 07 06 2017 2017 1 10 Copyright: © 2017 C. Purna Chand et al. 2017 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://nhess.copernicus.org/preprints/nhess-2017-66/ The full text article is available as a PDF file from https://nhess.copernicus.org/preprints/nhess-2017-66/nhess-2017-66.pdf

Sea level pressure (SLP) fields prevailing over Bay of Bengal (BoB) during Phailin, Lehar and Madi cyclones (2013) were estimated using University of Washington Planetary Boundary Layer (UWPBL) model with Oceansat-II Scatterometer (OSCAT) sea surface winds as an input parameter. Model performance in estimating SLP variations during cyclonic periods was investigated by comparison against cyclone reports of Indian Meteorological Department (IMD) and in-situ measurements. Pressure drop as per IMD reports were observed to be higher than model estimates, primarily due to limitations in scatterometer wind data. However, model retrieved pressure fields compare well against buoy measurements, with a bias of 0.0042, −0.1279 and −0.4406 observed for Phailin, Lehar and Madi cyclones respectively. The contrast in pressure drops between model estimates and IMD reports was investigated by comparing scatterometer winds against IMD reported maximum sustainable winds.