Building Essential Bridges between Ecosystem Data and Hydrodynamic-Ecosystem Models of Rhode Island Coastal Waters

Early work with a coupled hydrodynamic-ecosystem model developed for Narragansett Bay (RI, USA) highlighted the lack of knowledge about spatial and temporal patterns of zooplankton needed for model implementation and validation. Historically Narragansett Bay zooplankton have been sampled at one site, and the data resulting from this has been in the units of ind m^-3. This is not ideal for Regional Ocean Modeling System (ROMS), which uses the units mmolN m^-3. To begin to remedy this we have collected two replicate zooplankton samples at six sites throughout Narragansett Bay. These range from the mouth of the estuary to productive mid-Bay and to urban-impacted, water quality impaired northern embayments of the system. Station locations build from prior ROMS ecosystem models that predict hotspots of zooplankton growth and transport. Samples were taken every two weeks over the course of four months. One sample from each site was preserved for enumeration and the other was used for CHN analysis. The enumerations and CHN data can be linked by using values from literature for the dry weight and percent nitrogen of zooplankton. These will allow for a conversion from ind m^-3 to mmolN m^-3. These data can then be used for constructing initial and boundary conditions for the ROMS model simulations and subsequent data-model comparisons and model validation efforts. Model simulations run with initial and boundary conditions generated from the new data will be compared to previous ROMS ecosystem model runs to see if the zooplankton hotspots in Narragansett Bay remain the same.