Distributed Integrated Ocean Prediction System (DIOPS)
The Distributed Integrated Ocean Prediction System (DIOPS) initially began in 1999 as the Integrated Ocean Architecture (IOA) Program with funding from the Defense Modeling and Simulation Office and management from the DoD Modeling and Simulation Ocean Executive Agent. The goal of the IOA was to develop a simulation of the maritime environment within which diverse ocean domain processes can interact to provide support for maritime operations. Developed as a partnership among Argonne, the US Naval Research Laboratory at the Stennis Space Center, and the US Army Corps of Engineers Waterways Experiment Station, the IOA evolved to become the operational system now known as DIOPS. One key role of DIOPS is to predict surf conditions and detailed ocean behavior very near the shore. Because the oceans are coupled dynamic systems, it is important to model the entire ocean, not just the “surf zone” for accurate surf condition forecasts. Therefore, DIOPS uses an ensemble of ocean physics models interacting within the DIAS framework to address the full range scales—from the ocean basin to the shoreline—to accurately simulate conditions for amphibious landings and other littoral operations.
DIOPS receives multiple external data streams, including weather forecasts and models and bathymetric data. Weather inputs include global and regional weather forecast data from Navy numerical weather models, along with local observations for subregional and local scales. DIOPS also uses bathymetric data from low-, mid-, and high-resolution sources from archived datasets and collections from Navy SEAL teams and Unmanned Underwater Vehicles.
The WAM model provides global to regional scale spectral wind-generated wave prediction. WAM receives inputs from gridded 2D surface wind fields, 2D oceanic current fields, and 2D initial mean water depths to produce wave energy spectra at specified gridpoints, as well as mean and peak wave directions and frequencies at all gridpoints.
PCTIDES is the Navy's Globally Relocatable Tide and Atmospheric Modeling System. PCTIDES receives inputs from gridded 2D surface wind and pressure fields and gridded 2D initial mean water depths. Output characteristics include mean sea surface elevations at specific grid points, as well as mean depth integrated current at grid points and special nongrid station points.
The STWAVE model is unique because it provides both local scale and spectral wind-generated wave prediction models. The model takes tide levels, gridded 2D currents, and 2D initial mean water depths and generates predicted wave energy spectra and mean and peak wave directions and frequencies at specific gridpoints, taking into account depth-induced wave refraction.
The REFDIF model works at the subregional and local scale as a spectral wind-generated wave prediction model. It addresses bottom refraction and diffraction, for arbitrarily complex bathymetry. Similar to STWAVE, REFDIF takes tide levels at one point and gridded 2D initial mean water depths and provides wave energy spectra and mean and peak wave directions and frequencies at all gridpoints.
SURF is the Navy standard surf model. Concentrating on the local scale, SURF looks at winds from a single point, along with other oceanic and bathymetric data from other points along a 1D transect. The output includes width of surf zone, mean and peak wave heights, longshore currents, and a modified surf index prediction that can be used directly in operation planning.
DIOPS has proven to be faster, more accurate, easier to use, and far less prone to error than conventional methods of predicting surf conditions. Most important, the DIOPS environment can be modified and extended far more easily than most "model federations."
DIOPS has been used to support operational US Navy activities, including fleet exercises in 2002 and 2003 in the Baltic and Mediterranean. DIOPS was also utilized in field operations in support of littoral operations for Operation Iraqi Freedom in 2003.