Aerosol measurements and validation of satellite derived aerosol optical depth over the Kavaratti Cal-Val site

摘要

Aerosols are short-lived with a residual time of about a week in the lower atmosphere and are concentrated around the source of origin. Aerosols are produced by variety of natural processes as well as by anthropogenic activities; it gets distributed in the atmosphere through turbulent mixing as well as transported away from the source of origin and thus results in its large seasonal and spatial variability. In this study, the CIMEL sun-photometer measurements at Kavaratti calibration and validation site are used to characterize the aerosols' nature at the measurement site. Also, these in-situ measurements are used to validate the satellite sensor derived aerosol optical depth (AOD) parameter. The data analysis shows that the locally generated aerosols are mostly of marine aerosols and other natural aerosols are transported desert dust. The anthropogenic aerosols are transported from mainland and they are found during the pre-monsoon season. Also aerosol measurements for five years (2009 - 2015) are being planned for validating the satellite sensors derived AOD products namely: OceanSat2-OCM2, MODIS-Terra and MODIS-Aqua.