9310574 Bender As part of the U.S.JGOFS Arabian Sea Process Study effort to understand how physical forcing by the regional monsoons affects marine primary production and the regional carbon budget, the PI will carry out shipboard incubations of seawater samples to estimate seasonal photosynthetic production rates of molecular oxygen. Because the oxygen and organic carbon produced during photosynthesis are in a fixed proportion, these measurements will provide indirect measurements of primary production by making direct measurements of carbon. Similar shipboard laboratory studies will be carried out at different light levels to derive quantitative relationships that would then permit the estimation of in situ water column production rates from bio-optical data. Additionally, in order to calculate how much of the oxygen escapes to the atmosphere, the PI plans to make frequent measurements of dissolved oxygen and argon (a non-reactive gas that can be used as a mixing tracer) in the upper wind-mixed water column along the cruise track. The PI expects these studies to provide major insights into the oxygen and carbon dynamics of the Arabian Sea region and that these insights will benefit our understanding of the global carbon cycle. ***