Oceans are the most significant and prominent component of our – Blue Planet. Oceans play a key role in modulating various climatic processes of the Earth system. Ocean biota, in particular phytoplankton plays a fundamental role in regulating the Earth’s energy balance. In order to understand the complex nature of the ocean, the space platform is being used for observations of ocean surface and retrieval of various parameters. Currently, ISRO has three dedicated satellites in the orbit viz. Oceansat-2, SARAL and SCATSAT-1 for oceanographic observations. The data from these satellites is used to generate information on Photo-synthetically Active Radiation, ocean primary production, aerosol optical depth, total suspended sediments, suspended sediment concentration, ocean surface winds, ocean altimetry and ocean state forecast.

Oceansat-2 carries three payloads Ocean Colour Monitor (OCM), Ku-band Pencil Beam scatterometer (SCAT) and Radio Occultation Sounder for Atmosphere (ROSA) developed by the Italian Space Agency. The major applications of data from Oceansat-2 are identification of potential fishing zones, sea state forecasting, coastal zone studies and inputs for weather forecasting and climatic studies.

SCATSAT-1 carries Ku-band Scatterometer, which provides ocean surface wind vector data for weather forecasting, cyclone detection and tracking, ocean state monitoring and prediction.

SARAL carries a large Ka-band altimeter (35.75 GHz, 500MHz) to provide altimetric measurements designed to study ocean circulation and sea surface elevation leading to better understanding of the ocean meso-scale variability. SARAL secondary objectives include monitoring of the main continental waters level (lakes, rivers, closed seas), mean sea level variations, the observation of polar oceans, the study of continental ices and sea ices.