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The Arabian Sea, situated in the western part of the northern Indian Ocean is a tropical basin. It is bounded on the east by
the Indian peninsula, on the north by Baluchistan and Sindh provinces of Pakistan and on the west by the landmass of
Arabia and Africa. The environmental factors that influence this tropical basin are the seasonally changing winds from
the northeast during winter (November-February) and southwest during summer (June to September). Accordingly, the
waters of the basin will experience seasonal variations. The study aims at understanding the seasonal and inter-annual
variation of the Arabian Sea using satellite-derived data. The spatial domain selected for the present study is 40 degrees E and
78 degrees E longitude and equator to 30 degrees N. The remote sensing data with respect to sea surface temperature (SST), sea surface wind, sea surface height (SSH), and chlorophyll pigment concentration during January 2002 to December 2005 were
used to understand the spatio-temporal variability of the Arabian Sea. The monthly mean SST data was obtained from
Modis aqua, winds from Quikscat and chlorophyll pigment concentration from SeaWiFS. The SSH anomaly data was
obtained from the merged product - Topex/Poseidon ERS 1/2 satellite which is 7-day snapshot. The spatial resolution of
these data is 0.3 degrees latitude x 0.3 degrees longitude. Geographical information system (GIS) was used for processing and analysing the above parameters to determine the variability and detection of oceanic processes that are responsible for such
variability.The study showed a very strong inverse correlation between SST and chlorophyll concentrations. Arabian Sea
undergoes cooling during summer due to upwelling and advection, and in winter due to surface cooling under reduced
solar heating. Upwelling along the coasts of Somalia, Arabia, and the west coast of India brings cold and nutrient rich
sub-surface waters to the surface, which supports the observed high chlorophyll concentrations. During winter the
convective mixing in the northern Arabian Sea supports high chlorophyll pigment concentrations. Due to strong solar
heating, SST was warmest in spring (April), which supported least chlorophyll concentration.llite
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