The Coastal Marine and Atmospheric Environment Prediction System (CMAEPS) includes a modeling system, a web server, and a data server. The following figure gives the CMAEPS schematic.
Schematic of CMAEPS
The CMAEPS modeling system
The CMAEPS modeling system consists of an atmospheric model, the Weather Research and Forecasting (WRF) model, an ocean circulation model, the Princeton Ocean Model(POM), and a sea surface wave model, the Simulating WAves Nearshore (SWAN) model.
The atmospheric WRF model with the Advanced Research WRF (ARW) core is a fully compressible, non-hydrostatic numerical weather prediction model suitable for a broad spectrum of applications across scales ranging from meters to thousands of kilometers. WRF-ARW utilizes Arakawa-C grid, and it uses terrain-following hydrostatic pressure coordinate system in the vertical. WRF incorporates various physical processes including microphysics, cumulus parameterization, planetary boundary layer, surface layer, land-surface, and long-wave and short-wave radiations, with several options available for each process.
The SWAN wave model is a third generation wave model. It solves the wave action balance equation in both spatial and spectral spaces. SWAN considers various source and sink terms including wind input, wave-wave interaction, and dissipation terms. In shallow water, the effects of triad wave interaction and depth-induced wave breaking are also included in SWAN. Wave characteristics such as significant wave height (SWH) can be obtained from the wave action (spectrum) in the governing equation.
The POM ocean model is a three-dimensional, primitive-equation model using the Arakawa-C grid staggering and a sigma coordinate in the vertical. The turbulence closure scheme employed in POM is Mellor-Yamada scheme. In addition, wave-enhanced upper-ocean turbulent mixing due to wave breaking was incorporated into the Mellor-Yamada turbulence closure scheme by Mellor and Blumberg (2004), in which the effect of wave breaking on upper-ocean turbulent mixing is considered by specifying a wave-enhanced upper boundary condition depending on friction velocity. POM has been widely used in applications from estuaries to coastal ocean circulation as well as operational ocean forecasting.
The modeling system is run on the NCSU IBM Blade Center Linux Cluster (henry2), which has 966 dual Xeon compute nodes with Intel Xeon Processors.
The henry2 Linux cluster
- sea level pressure; surface wind, temperature, humidity; maximum reflectivity; precipitation; maximum CAPE; etc.
- upper air geopotential height, temperature, wind, humidity, and vorticity, etc.
- water elevation
- wave height, wave direction, and wave period
Thematic Realtime Environmental Distributed Data Services) data server were utilized to set up the data server. Various CMAEPS near realtime model forecasts, including surface atmospheric forcings, storm surge water elevation and depth-averaged (2-d) current, and surface wave height, direction and period, can be accessed from the data server.