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Impact of episodic pulse of more than 5% of the global dissolved and particulate riverine C load fro Ganges-Brahmaputra is perhaps the most important of the natural and human induced interactive forcings influencing future capacity of CO2 assimilation of the Indian Ocean.Bay of Bengal is one of the high productive areas of the world oceans and very high organic carbon fluxes of more than 3 g m -2 y-1 have been recorded in sediment trap experiments.Any potential climate change impact would enhance the uncertainty about the future effect on the flux from Brahmaputra-Ganges on the processes of the Indian Ocean.If any reduction in C flux materializes,Indian Ocean will starve of the current carbon flux with serious impact on the air-sea CO2 exchange and anthropogenic CO2 inventories.Air-sea CO2 flux variability impact due to such variations in entrained terrestrial input could be more pronounced than surface temperature or wind speed.Large uncertainty already exists concerning uptake of carbon by the Indian Ocean due to insufficient knowledge of processes controlling carbonate chemistry.The settling of particulate organic carbon decreases the total C and pCO2 of the surface layers,whereas the removal of carbonate from surface waters aids in increasing atmospheric CO2 by shifting the carbonate equilibrium.Changes in the ocean circulation due to reduced stratification would drastically change future anthropogenic CO2 flux.While carbon flux between upper and mesopelagic layers would be affected,it would be the reduced net flux of C that will control the ocean-climate interaction.