Advanced Fisheries Management Information System

The following pages present a coupled physical/biological(N-P-Z)/Cod simulation (with tides) which has produced a real-time nowcast and forecast for Georges Bank, including the effects of the assimilation of sea surface temperature (SST) and sea surface color (SSC) data. The product package includes daily maps of surface temperature (° C) with superimposed vectors of sub-tidal velocity; chlorophyll at 15m (: g/L); bottom temperature (° C) with superimposed vectors of sub-tidal velocity; and, Cod abundance (non-dimensional units, logarithmic scale) at the bottom. Additional products (e.g. forecast tendency, etc.) are under development. The simulation was launched on Friday 21 April. There is no remotely sensed (due to extended inclement weather) or real-time in situ data available to be included in the assimilation process for this simulation. The simulation includes the effects of previously assimilated remotely sensed data.

The sea surface temperature and velocity fields indicate generally clockwise circulation around Georges Bank and flow out of the Gulf of Maine through the Great South Channel. In the surface layers the wind-driven circulation is less predominant than last week (e.g. see April 19). The southern edge of the domain is still dominated by interactions with the shelf-slope front but to a lesser extent than last week. The details of the front and eddying associated with the shelf/slope front are expected to be improved when the forecast is generated from a nested or larger domain (a planned upgrade) and multivariate assimilation of SST and compatible salinity is carried out. Compared to last week, notice also the build-up of the surface stratification in the regions of weak tidal mixing (e.g. increase of surface T on the northern flank). Except for the forecast warming of the upper layers by atmospheric forcing, the physical situation for April 25 is forecast to be similar to that of April 24. Chlorophyll shows enhancement over the bank and Nantucket Shoals with some westward advection over the bank. The bottom T shows highest values over the western portion of the bank. Bottom flow patterns have remained similar to what they were on April 20: they are similar to the surface velocities although flow across the bank is more noticeable at depth (note the change in scale to 5 cm/s). The warmer temperatures along the southern edge of Georges Bank mark the foot of the shelf-slope front. Cod abundance is designed to follow the tendency of Cod to be attracted to the 5° C isotherm. Enhancement along the southern edge of the bank is the result of flow convergence set up by the interaction of flow around the bank with the shelf-slope front. Other significant abundances are notable to the west and northwest of the bank.

Each simulation runs for seven days. A Monday product includes a nowcast and one day of forecast. A Wednesday product includes a nowcast and two days of forecast. Nominally, SSC is assimilated for the first 2 days of each simulation, and SST is assimilated for the second and third days. If not available, the last available data is assimilated. FNMOC atmospheric forcings are utilized on a twice-daily basis throughout the simulation with analyses used where possible and forecasts thereafter. The initialization field for each simulation is a restart from the previous week's simulation. Forecasts for Monday-Tuesday are initialized from the Tuesday fields of the previous Wednesday-Friday forecast period, while forecasts for Wednesday-Friday are initialized from the Friday fields of the previous Monday-Tuesday forecast period.

Nowcast - April 24, 2000

Surface Temperature and Velocity	Chlorophyll at 15m

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Forecast - April 25, 2000

Surface Temperature and Velocity	Chlorophyll at 15m

Nowcast - April 24, 2000

Bottom Temperature and Velocity	Cod Abundance

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Forecast - April 25, 2000

Surface Temperature and Velocity	Cod Abundance

The Advanced Fisheries Management Information System (AFMIS) is intended to apply state-of-the-art multidisciplinary and computational capabilities to high-frequency operational fisheries management. The system development is aimed toward: 1) utilizing information on the "state" of ocean physics, biology, and chemistry; the assessment of spatially-resolved fish-stock population dynamics and the temporal-spatial deployment of fishing effort to be used in the operational management of fish stocks; and, 2) forecasting and understanding physical and biological conditions leading to recruitment variability. Systems components are being developed in the context of using the Harvard Ocean Prediction System to support or otherwise interact with the: 1) synthesis and analysis of very large data sets; 2) building of a multidisciplinary multiscale model (coupled ocean physics/N-P-Z/fish dynamics/management models) appropriate for the northwest Atlantic shelf, particularly Massachusetts Bay and Georges Bank; 3) the application and development of data assimilation techniques; and, 4) with an emphasis on the incorporation of remotely sensed data into the data stream.

AFMIS is designed to model a large region consisting of most of the Northwest Atlantic (NWA). Several smaller domains, including the Gulf of Maine (GOM) and Georges Bank (GB) are nested within this larger domain. This provides a capability to zoom into these domains with higher resolution while maintaining the essential physics which are coupled to the larger domain. AFMIS will be maintained by the assimilation of a variety of real time data. Specifically this includes sea surface temperature (SST), color (SSC), and height (SSH) obtained from several space-based remote sensors (AVHRR, SeaWiFS and Topex/Poseidon). The assimilation of these data will allow nowcasting and forecasting over significant periods of time.

The Real-Time Demonstration of Concept (RTDOC) nowcasting and forecasting exercise is intended to demonstrate important aspects of the AFMIS concept by producing real time coupled forecasts of physical fields, biological and chemical fields, and fish abundance fields. It is intended to verify the physics, to validate the biology and chemistry but only to demonstrate the concept of forecasting the fish fields, since the fish dynamical models are at a very early stage of development. In addition, it is intended to demonstrate the integrated system concept and to consider the implication of coupling a management model. The goals of the RTDOC are: 1) to demonstrate real-time nowcasting and forecasting of coupled physical, biochemical and fish distribution fields and 2) utilize the data obtained to produce information relevant to fisheries management. These goals are based on several hypotheses, including the assumption that a dedicated ocean prediction system (AFMIS) which properly incorporates the interaction processes and feedback between the three dynamics can nowcast and forecast state variables of interest and that fish abundance distributions vary over 1 to 2 week time scales in ways that are important for fisheries management and fishing. The demonstration of concept has been structured to directly address these hypotheses by providing results in near real time to a variety of users.

Observational System Simulation Experiments (OSSEs) continue to develop the additional capabilities for AFMIS. Such OSSEs have been carried out for over a year in three domains: GB, GOM and NWA. The OSSEs in the GB domain involved the implementation and calibration of the physical (tidal effects, turbulent mixing, etc.), biological (initial adjustment, rates and other parameter testing) and Cod models based on NMFS MARMAP and US GLOBEC data. As improvements to the AFMIS system are completed, the AFMIS products will be upgraded and expanded.

UMass.-Dartmouth: Brian J. Rothschild - Lead Principal Investigator, J. Bisagni, A. Cabeza, A. Gangopadhyay, H.-S. Kim, L. Lanerolle, G. Strout, and M. Sundermeyer.

Harvard University: Allan R. Robinson - Principal Investigator and RTDOC Chief Scientist, P.J. Haley, Jr., P.F.J. Lermusiaux, W.G. Leslie, and C.J. Lozano

Physical Sciences, Inc.: Merlin Miller - Principal Investigator

The AFMIS RTDOC is supported by NASA and ONR.