ASLO/TOS 2004 Ocean Research Conference

SS2.07 (poster)
PRIMARY PRODUCTION CALCULATIONS IN THE MID-ATLANTIC BIGHT, INCLUDING EFFECTS OF PHYTOPLANKTON COMMUNITY SIZE STRUCTURE
Mouw, C.B.
cmouw@gso.uri.edu
University of Rhode Island, Graduate School of Oceanography, South Ferry Road, Narragansett, RI 02882 United States
Yoder, J A
jyoder@gso.uri.edu
University of Rhode Island, Graduate School of Oceanography, South Ferry Road, Narragansett, RI 02882 United States

An absorption based primary production model that includes the effects of phytoplankton community size structure has been developed for continental margin and adjoining Gulf Stream waters of the Mid-Atlantic Bight (MAB). The model utilizes, previously determined seasonal cycles of phytoplankton community size structure, representative absorption spectra, remotely sensed chlorophyll concentration, sea surface temperature and photosynthetically active radiation, in situ determination of mixed layer dynamics, and previously determined nitrate concentration. Primary production was calculated every month for 5-years for study areas representing shelf, shelf-break, slope and Gulf Stream waters. The calculations included both light- limited and nutrient- limited conditions of the MAB seasonal cycle. Interannual temporal variability correlated well to wind mixing intensity. Seasonal trends in temporal primary production were evident; however variability between the mean daily production rates for each month over the study period displayed no apparent trends. Relative to cell size seasonality, primary production was regulated more by biomass than light acquisition capability. Comparison of remotely-based production estimates and estimates made with in situ depth dependent data revealed that approximately 40 percent of daily production was missed by satellite-based estimates.