Report of the

U.S. GLOBEC Georges Bank

Science Meeting

18 - 20 November 2003, Rhode Island

 
Cover Page

Acknowledgements

Introduction

Narrative

Presentation Abstracts

Poster Presentations

Appendix I: Agenda

Appendix II: List of Participants

Appendix III: List of Planned Publications


Nested Modeling Studies in the Northwest Atlantic

Haidvogel, D.B.1, J. Wilkin1, K. Fennel1, H. Arango1, P. Goodman1
1Institute of Marine and Coastal Sciences, Rutgers University, New Brunswick, NJ 08903

The Regional Ocean Modeling System (ROMS v2.0) has been implemented for the continental shelf and adjacent deep ocean of the U.S. east coast (Figure 1). The present configuration has 10 km horizontal resolution, 30 vertical levels, and is embedded within a North Atlantic ROMS model forced with 3-daily average winds and climatological buoyancy fluxes. The embedding procedure imposes external remotely forced mesoscale and seasonal variability with few open boundary artifacts. Coastal freshwater inputs are applied using observed USGS river flow data. The model exhibits recognized features of local and remotely forced circulation: namely, wind-driven upwelling in the MAB, buoyancy-driven river plumes, low salinity on the MAB inner shelf, retention of passive particles in the shelf-slope front, and interactions of Gulf Stream warm rings with the slope region.

Studies are underway in a variety of nested regions within the Northwest Atlantic, as shown in Figure 2. The scientific and technical issues addressed in these studies include a better understanding of regional processes (wind-driven upwelling and associated bio-optical response, surface boundary layer dynamics under low wind speed conditions, material transport within buoyancy-driven plumes, etc.) as well as the development of data-assimilative regional prediction systems.

As one component of these ongoing studies on the Northwest Atlantic shelves, we are developing realistic simulations of shelf circulation, mesoscale events, and interannual variability associated with major climate modes such as the North Atlantic Oscillation. This will be achieved by improving the basin-scale embedding procedure to use results from the PARADIGM modeling effort (http://www.gso.uri.edu/paradigm/), and the retrospective North Atlantic eddy-resolving models of the Mercator (www.mercator.com.fr) and HYCOM (hycom.rsmas.miami.edu) groups that assimilate satellite altimetry, sea surface temperature, and Argo float profiles. This will impose observed weekly to interannual time scale variability (predominantly from altimetry) on the physical circulation.

Haidvogel Figure 1
Figure 1. Simulated temperature at 100 meters for 16 September 1993 obtained from ROMS v2.0. Inset shows surface salinity and velocity in the MAB-SAB. Gray line defines the open boundary of the inner domain at which the embedding conditions are applied with negligible apparent discontinuity.

Haidvogel Figure 2
Figure 2. Nested domains currently in use or proposed within the Northwest Atlantic: (1) the Northeast North Atlantic domain (see also Fig. 1), (2) the Northeast Observing System, (3) the Coupled Boundary Layer Air-Sea Transfer domain, (4) the Lagrangian Transport and Transformation Experiment, (5) the NY/NJ Bight domain, and (6) the region of the proposed Caribbean Sea prediction system.

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