Diurnal Variability of Organic Carbon Distributions and Phytoplankton in Chesapeake Bay

The full effects of fossil fuel combustion on the carbon cycle are not well understood. To address rising environmental concerns, NASA is studying a new satellite mission concept called Geostationary Coastal and Air Pollution Events (GEO-CAPE), which will take more frequent images than the two current ocean color satellite sensors, SeaWiFS and MODIS-Aqua. GEO-CAPE will be able to study the diurnal variation associated with natural processes, climate change, and other human impacts on the coastal ocean. The purpose of this study was to collect preliminary data for organic carbon distributions and phytoplankton in Chesapeake Bay through high frequency sampling. Local water samples showed greater regional and daily differences in colored dissolved organic matter (CDOM), which may be explained by river discharge. Small diurnal variation likely due to the tidal cycle was also observed. Mean particulate organic carbon (POC) showed more substantial diurnal variation, which coincided with diurnal variability in chlorophyll from algal biomass. This variability supports the need for the GEO-CAPE satellite mission to further our understanding of the ocean’s role in the carbon cycle.