Seasonal occurrence of unique sediment plume in the Bay of Bengal

Movement of sediment plumes, detectable from ocean colour sensors (Klemas et al, 1975, Khorram, 1981, Nezlin and DiGiacomo, 2005), primarily depends on coastal circulation (Fong, et al 2002). Hence, sediment plumes, become tracers for studying circulation patterns. Indian remote sensing satellite, Oceansat-1, carries ocean colour monitor [OCM] sensor. Using these data, we studied the suspended sediment concentrations [SSC] during 1999-2006 and observed a unique plume off Krishna-Godavari river Basin (KGB). The KGB is located in the central part of east coast of India between 16 ° 43 ' and 17 ° 00 ' N, and 82°15 ' and 82 ° 22 ' E [Figure-1a]. Though high sediment concentration is present all along the east coast of India, the offshoot of the plume is present only at Kakinada Coast. The presence, extent, orientation and intensity of this plume have both seasonal and inter annual variations. We superimposed the geostrophic currents available in website www.aoml.noaa.gov/phod/dataphod/work/trinanes/INTERFACE over the OCM observations to delineate this plume and the current pattern that controls its behaviour. These geostrophic currents were estimated using sea surface height anomalies from the available altimeters and a climatological mean dynamic height fields from the OCCAM (ocean circulation climate advanced modeling). The details of this ocean model are available i