THE MEGHA-TROPIQUES SATELLITE MISSION COMES TO AN END

After more than 10 years of observations, the Franco-Indian satellite was decommissioned and deorbited on 7 March. Launched on 12 October 2011 by the Indian launcher PSLV C18, as part of a collaboration between ISRO and the French space agency CNES, this mission was intended to carry out studies on tropical climate and weather conditions.

Megha-Tropiques is designed to study convective systems in the atmosphere, and more specifically to analyse the water cycle through the transport and distribution of water vapour, the life cycle of convective systems and energy exchanges in the equatorial belt. Tropical zones are where the most significant energy exchanges occur: radiative exchanges, latent heat exchanges, transport of constituents and energy through dynamic processes. The challenge is therefore to increase our knowledge of the hydrological and energy processes in tropical zones and their influence on the global circulation of the atmosphere, the oceans and climatic variations.

Thanks to its circular orbit inclined at 20° to the equator, which allows multiple observations in tropical regions, Megha-Tropiques is a unique satellite for climate research and for helping scientists to refine prediction models.

Since 2018, a technical problem has disrupted the recording of data in the satellite’s mass memory, but scientists have nevertheless managed to obtain data despite the satellite’s initial mission duration of three years.

AERIS manages and distributes Megha-Tropiques’ Level 1 and Level 2 products, as well as data from the MADRAS, SAPHIR and SCARAB instruments. Level 1 processing is carried out by ISRO and the data is transmitted in slightly delayed time to our ICARE data and services centre via a dedicated line. They are available by acquisition segment or by complete orbit and in their raw geometry or resampled in a grid common to all the instruments. Level 2 products are processed scientifically by ICARE. The products are archived and distributed by ICARE. In addition, ICARE produces the TAPEER (Tropical Amount of Rainfall with Estimation of ERors) product, which is a level 4 product combining SAPHIR data with data from other microwave instruments in the GPM constellation and with data from the corona of geostationary meteorological satellites.