This is a $990,863.28 grant awarded by the National Aeronautics and Space Administration (NASA) to The Pennsylvania State University (Penn State) to study the impacts of climate change and human activities on carbon cycling in the Biscayne Bay and Tampa Bay estuaries. The primary objectives are to: (1) synthesize historical water quality data, (2) measure key carbon fluxes and stocks, (3) develop remote sensing algorithms for primary production and dissolved organic carbon, (4) create mass-balance box models of carbon and related constituents, and (5) analyze the model results to determine factors affecting carbon cycling. The research aims to address hypotheses related to the effects of tropical cyclones, declining nitrogen loading, streamflow changes, and spatial variations in net ecosystem production. This grant is responsive to the goals of NASA, USDA-NIFA, DOE, and NOAA to improve understanding of carbon cycling and global environmental change. The contract does not have a set-aside designation.