Introduction

The NASA Aerosol Robotic Network (AERONET) will begin a four-year intensive field campaign, called TIGERZ, on April 2008 to measure aerosol microphysical and optical properties over India. Collaborating entities in India include the Ministry of Earth Sciences, IIT Kanpur, IIT Kharagpur, and the Indian Space Research Organization (ISRO). India agencies will hold campaigns on measuring the monsoon and thunderstorms over India: Continental Tropical Convergence Zone (CTCZ) and STORMS. The AERONET/CALIPSO campaign will share existing resources (e.g., facilities and manpower) established for the ongoing India-sponsored campaigns and utilize equipment through other international partnerships with AEROCAN (Canada), PHOTONS (France), and Finnish Meteorological Institute (Finland). The AERONET campaign initiative is expected to continue periodically through 2011.

The AERONET sun photometer measurements will emphasize high temporal aerosol optical depth (AOD) measurements as well as more frequent almucantar and principal plane radiance measurements to provide input for the joint inversion products with CALIPSO. A number of sun photometer instruments (5-7) as well as other equipment, such as lidar and rain gauges, will be moved into the A-Train satellite footprint to provide the most reliable measurements along track. In addition to CALIPSO, MODIS and MISR instruments will also benefit from the intensive sun photometer network in India. Furthermore, aerosol and weather modeling will also find these data beneficial for validation.

India experiences distinct seasonal changes in aerosol concentration controlled mainly by the monsoon. These atmospheric aerosols over India can be transformed by chemical reactions or ambient atmospheric conditions. The complex aerosol environment includes primarily dust, sulfates, and black carbon with lower concentrations of organic carbon and sea salt. These primary aerosol constituents can aggregate or become hygroscopic to form complex mixtures difficult to determine from satellites. Further difficulty arises in remotely sensing aerosols over India due to the proximity of the Himalayan Mountains and bright surfaces.

Background

The Continental Tropical Convergence Zone (CTCZ) is a four year program under the Indian Climate Research Program that has the major objective to understand the mechanisms leading to space-time variation of the CTCZ and the embedded monsoon disturbances during the summer monsoon. A multiscale approach with study of the major interacting scales including planetary, regional, synoptic and mesoscale is essential. For adequate observations on all important time-scales from diurnal to intra-seasonal and interannual, a multi- year program is planned.

The Ministry of Earth Sciences (MoES) is mandated to provide the India with the best possible services in forecasting the monsoons and other weather/climate parameters, ocean state, earthquakes, tsunamis and other phenomena related to earth systems through well integrated programs. In addition, the Ministry also oversees science and technology for exploration and exploitation of ocean resources (living and non-living), and play nodal role for Antarctic/Arctic and Southern Ocean research. The Ministry’s mandate is to monitor Atmospheric Sciences, Ocean Science & Technology and Seismology in an integrated manner.