Assessment of Vertical Ozone Profiles from INSAT-3D Sounder Over The Central Himalaya
Prajjwal Rawat, Manish Naja, P. K. Thapliyal, Shuchita Srivastava, Piyush Bhardwaj, Rajesh Kumar, Samaresh Bhatacharjee, S. Venkatramani, Sudhanshu Tiwari, Shyam Lal
Abstract
Vertical distribution of ozone has been obtained for the first time using INSAT-3D for the period 2013-2017 over the central Himalaya and validated utilizing balloon-borne observations from a high-altitude site in Nainital (29.4N, 79.5E, 1793 m amsl). The INSAT-3D retrieved ozone profiles captured ozone gradient and ozone peak altitude successfully, despite only one IR channel for ozone. This demonstrates the capability of the INSAT-3D Sounder in capturing the observed features, with a smaller bias in the stratosphere and somewhat larger bias in the troposphere. Total ozone column from INSAT-3D showed maximum difference of 8% with ozonesonde-derived total ozone column. Larger ozone bias in the lower troposphere could be attributed to lower reliability of regression coefficient and INSAT-3D channel constraints itself, whereas high variability near the tropopause is possibly due to low ozone, poor temperature retrieval near the tropopause and stratosphere-troposphere transport process in the Himalayan region.