Puerto Rico and the Virgin Islands

Caption: Salinity and current vectors in the large scale ROMS grid (parent grid)

Caption: Sea surface height (SSH) and current vectors in the small scale ROMS grid (child grid) centered on the Mona Passage. The two successive snapshots show the formation of a cyclonic eddy around Mona Ilsand.

Caption: Sea surface salinity (SSS) and current vectors from the intermediate grid centered on the Virgin Islands. The square show the high resolution grid centered on St Thomas. Both SSS and current vectors are plotted for that grid showing continuity at the boundary between the two nested grids

Caption: Temperature and current vectors in St Thomas zoom showing upwelling on the northern coast.

Description:

The model domain (first large scale resolving grid or parent grid) is the northeastern Caribbean encompassing some of the Windward Islands, the US and British Virgin Islands, Puerto-Rico, and Dominican Republic (14-23 N, 71-61 W). A zoom on the Island of St Thomas is done through two nested (child)grids in the parent grid. They are nested on-line (run simultaneously) using the Adaptive Grid Refinement in Fortran (AGRIF - Blayo and Debreu 1999) package. A two-nested grid simulation, using the same parent grid was used to zoom on Mona Island. The child grid encompasses western Puerto-Rico and the Mona Passage. The parent grid simulation was used as a nature run.

Resolution:

The horizontal resolution of the simulation of the parent grid is 6 km, first child grid 2km and third child grid 700 m. The three models have 25 vertical layers. The bathymetry of the model is a blend between Global Topographic data (GTOPO30- 1km) for the low resolution and the National Geophysical Data Center (NGDC - 90 m) for the high resolution grid.

Nested:

Currently, No. Next step is to use the Atlantic HYCOM simulation at the boundaries.

Initial conditions:

Currently, World Ocean Atlas 2001 climatology; in the future the Atlantic HYCOM simulation.

Outer conditions:

Currently, model variables of the ocean state (temperature, salinity) at the open ocean boundaries were relaxed to the monthly Levitus ocean climatology ( Word Ocean Atlas). In the future boundary conditions will be provided by the Atlantic HYCOM simulation.

Tides:

Tides were set at the boundaries by the TPXO6 global tide model.

Forcing:

Monthly varying surface fluxes (wind, rain, solar, radiative heat fluxes, evaporation) were obtained from the Comprehensive Ocean Atmosphere Dataset ( COADS) climatology. In the future, Navy Operational Global Atmospheric Prediction System (NOGAPS) and Coupled Ocean Atmosphere Mesoscale Prediction System (COAMPS) will provide the atmospheric forcing. Bulk fluxes capability of the ROMS model will be used.

Applications:

This simulation was used:

(1) to explain the genetic break in Acropora Palmata reef building coral by the fresh water driven seasonality of the eastern Caribbean Sea (Baums et al., 2006).

(2) to understand the origin of the seasonal variability of the mesoscale acitivity in the eastern Caribbean (Cherubin and Richardson, 2007).

This simulation is used:

(3) to study the fate of grouper larvae from spawning aggregations (USGS project)

(4) to study the connectivity patterns of shallow reef building coral and Nassau groupers populations in the US Virgin Islands

(5) to understand the origin and patterns of the 2005 coral bleaching event

(6) the Puerto-Rico grid will be turned into a predictive model using the Atlantic HYCOM and the COAMPS forecasts

Contacts:

Laurent Cherubin - lcherubin@rsmas.miami.edu

Nasseer Idrisi - nidrisi@uvi.edu

Jorge Capella - j.capella@caribe.net

Claire Paris - cparis@rsmas.miami.edu

Iliana Baums - ibb3@psu.edu