Carbon Fluxes on the Florida shelf

Lack of baseline data on carbonate saturation state and pCO2 fluxes on the west Florida shelf, a low- gradient calcium carbonate platform, constrains the ability of managers and scientists to predict aspects of ecosystem change. Ecosystem change may result from a number of factors, such as climate change, ocean acidification, riverine and groundwater contribution, and biogeochemical cycling. Maps and models of pCO2 fluxes and carbonate saturation state are needed for the Florida shelf where significant decline of carbonate ecosystems, fishery habitats, and calcifying organisms are predicted over the next decade. To address critical information gaps and an incomplete understanding of nearshore carbon flux variability, the U.S. Geological Survey (USGS) is conducting a field campaign with the University of South Florida (USF) and National Oceanographic and Atmospheric Administration (NOAA) to acquire baseline pCO2, pH, total dissolved inorganic carbon (DIC), and total alkalinity (TA) on the west Florida shelf. These data are being used to model nearshore to offshore regional pCO2 and carbonate saturation state and, in conjunction with acquired habitat data, will be used to describe and interpret habitat change over time. Using the Multiparameter Inorganic Carbon Analyzer (MICA) developed by USF, data on air and sea pCO2, pH, DIC, and TA were collected underway during July and August 2008 cruises on the west Florida shelf. Maps depicting carbonate saturation state of the marine water, underlying sediment, and habitat data show varying relations. An additional cruise is planned for winter 2009.