| Abstract: |
The presentation will provide an introduction to ChesROMS v1.2, an open source prediction model of the Chesapeake Bay that is based on the 3-D primitive equation numerical ocean circulation model ROMS (Regional Ocean Modeling System). The initial hydrodynamic implementation of ChesROMS has been employed to provide input to empirical harmful algal bloom (HAB) predictive models. Recently, ChesROMS has been extended to include a fully coupled Nitrogen-Phytoplankton-Zooplankton-Detritus (NPZD) type dynamic lower trophic level ecological component that simulates the Bay’s biogeochemical cycles. The model framework provides necessary components for retrospective and near real time data acquisition and pre- and post- processing, which make it suitable for hindcasting, nowcasting and short term forecasting of bay-wide physical, ecological and water quality conditions. A web based GIS visualization system has also been developed for dissemination. Key aspects of the biogeochemical model include point and non-point (diffusive) nutrient inputs, atmospheric nutrient deposition, light attenuation by particulate and dissolved components, and mechanistic implementation of water column and benthic denitrification. The Bay’s open boundary is relaxed to climatological nutrient and biomass concentrations and physical properties. The simulated biogeochemical state variables include nitrate, ammonia, phytoplankton, chlorophyll a, zooplankton, dissolved organic nitrogen, detritus, dissolved oxygen and inorganic suspended solids. An overview of the model components, strategies and implementation specifics will be presented. The system is initially deployed at the NOAA Chesapeake Bay Office for nowcasting and three-day forecasting with a daily updating cycle. An initial assessment of results from re-forecasting years 2008 and 2009 will be presented.
Keywords: ChesROMS, Chesapeake Bay, circulation, ecological forecasting, open source community modeling |
