GODAE is sponsored by
The CSS projects
Gulf of Mexico
Surface velocity and SST (2004-01-02) West Florida Shelf ROMS (inside the dashed line)
North Atlantic HYCOM (outside of this area)
P13 - HYPO (NOPP-CODAE) / Gulf of Mexico
Project name, acronym
HYCOM Coastal Ocean Hindcasts and Predictions: Impact of Nesting in HYCOM GODAE Assimilative Hindcasts (our shorthand name for this project is NOPP-CODAE). The participants are RSMAS, University of Miami, Naval Research Laboratory, Stennis Space Center, Naval Research Laboratory, Monterey, Planning Systems, Inc., and the University of South Florida.
Domain
Coastal United States from the northern Gulf of Mexico (GoM) to east-central Florida. We are focusing on three nested domains:
(1) Northern GoM
(2) West Florida Shelf
(3) South Florida domain
The latter domain including the Straits of Florida, Florida Keys, and Florida Bay and is part of the environmental monitoring effort being conducted as part of the Everglades restoration effort.
Objectives
Determine the impact of initial and boundary conditions provided by HYCOM GODAE ocean nowcasts and forecasts on the capability of nested models to hindcast and predict the coastal ocean environment.
Evaluate the quality of coastal ocean hindcasts and predictions against observations that include existing elements of the Coastal Ocean Observing System.
Identify the most useful observations for evaluating and improving coastal ocean models that should be maintained as part of a coastal observation network.
Provide feedback and recommendations designed to improve the HYCOM GODAE product. This information will also help improve other ocean nowcast products produced as part of GODAE.
Evaluate HYCOM performance as a nested coastal model against other model types (POM, ROMS). This comparison will be performed in the West Florida Shelf domain and involves collaboration between RSMAS and the University of South Florida.
Perform scientific studies in all three nested domains. Topics will include, but are not limited to,
- impact of offshore currents (Loop Current and eddies, Florida Current) on coastal circulation (all domains)
- shelfslope exchanges (all domains)
- impact of the Mississippi river plume (locally in the northern GoM, remotely in the other two domains)
- the coastal ocean response to hurricanes (all domains).
Results will also support other funded projects such as the SEED program in the northern GoM, the coastal oceanography projects being conducted along the West Florida Shelf at the University of South Florida, and the Everglades restoration project that is substantially supporting the modeling effort in the South Florida domain. We are providing physical fields from the West Florida Shelf and the South Florida domains to other RSMAS researchers interested in biochemical processes such as larval recruitment, red tide, etc.
Approach
Each of the three coastal modeling efforts will conduct nested ocean hindcasts, and then use all available in-situ observations to evaluate model performance. Sensitivity to initial and boundary conditions will be assessed by nesting the models within different outer model products.
For this project, these products will be provided by the evolving HYCOM nowcast-forecast system. Three initial products will be evaluated:
- The original product that assimilated satellite altimetry and SST using optimum interpolation with vertical projection of SSH anomalies
- Nowcasts produced by the NCODA assimilation system based on objective analysis;
- The operational NCEP HYCOM nowcast-forecast system based on objective analysis
- Nowcasts produced by the ROIF assimilation system.
For evaluation, these runs will be compared to each other, to the hindcast fields that provided initial and boundary conditions, and to in-situ observations. Evaluation will be performed not only on coastal hindcasts, but also on forecast runs initialized by different products. Two sets of forecast runs will be performed, one where the boundary conditions are held constant and one where they are provided by HYCOM GODAE assimilation system forecasts. Outer model nowcasts will be generated using different subsets of all available observations. Evaluation of coastal models nested within these different products will help identify those observations that lead to the most improvement and thus have priority in being maintained as part of the Coastal Ocean Observing System. Evaluation of coastal models will also be performed to determine
- how often should boundary condition fields be provided (daily, weekly, ..)
- determining where the boundaries of the nested domains should be situated and how wide they should be
- identifying and using the best available atmospheric forcing (e.g., COAMPS, ETA, ...).
Project status
At present, the first sets of outer model archives within which the coastal models will be nested either have been, or are being generated, for the initial study interval (2004-2005). The NCODA and ROIF nowcast products are being developed within a HYCOM domain spanning the Gulf of Mexico. Model files have been set up for two of the nested coastal domains (West Florida Shelf and South Florida) and test nested simulations have been run. During the remainder of 2006, multiple nested nowcasts will be conducted for years 2004 and 2005.
(Last Updated: 17-01-2008)