System Architecture

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CBOLT is a distributed system of server- and client-side components that allow users to run a particle tracking model and then visualize the output as a set of geospatial features within in a Web-based mapping interface. On the client-side of the architecture, users interact with several Web sites developed using Environmental System Research Institute's (ESRI) ArcIMS internet map server software. The server side of the architecture consists of several custom-developed models and components in conjunction with a Microsoft SQL Server relational database and ESRI's ArcSDE enterprise geodatabase management software. The system is designed to be flexible so that additional oceanographic models can be incorporated into the architecture, so long as their output is in the NetCDF file format. A more detailed description of each component within the CBOLT system appears below.

CBOLT System Architecture Diagram. Click on the image to view a larger version.

Chesapeake Bay 3-D Physical Oceanographic (C3PO) Model

• Finite element hydrodynamic model
• Baroclinic circulation is modeled with full salinity and temperature fields
• Uses real time observational data for surface wind forcing and to prescribe the non-tidal water level height at the mouth of the bay
• Output is in NetCDF format

Particle Tracking Model

• Uses hydrodynamic model output in conjunction with biological behaviors to predict larval transport
• Data inputs for the model are flexible; future hydrodynamic models can be incorporated, so long as their output is written to the NetCDF format

Model Controller

• Passes user defined input parameters to particle tracking model
• Once model results are written to disk in NetCDF format, returns URL of output location for data retrieval

CBOLT Controller

• Manages CBOLT user session
• Facilitates data flow through system architecture

Spatial Processor

• Retrieves particle tracking model output
• Creates geospatial features (starting and ending points, tracks, endpoint distributions) and loads them into ArcSDE enterprise geodatabase

Session / Spatial Database

• Stores unique ID for each user session
• Stores geospatial features created from particle tracking model output

Internet Map Server

• Produces map images from model output data sets
• Provides several spatial analysis functions (buffer, query) with ancillary data sets