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During September 2008 and February 2009, the NR/V Alliance extensively sampled the waters of the Sea of Marmara within the framework of the Turkish Straits System (TSS) experiment coordinated by the NATO Undersea Research Centre. The observational effort provided an opportunity to set up realistic numerical experiments for modeling the observed variability of the Marmara Sea upper layer circulation at mesoscale resolution over the entire basin during the trial period, complementing relevant features and forcing factors revealed by numerical model results with information acquired from in situ and remote sensing datasets. Numerical model solutions from realistic runs using the Regional Ocean Modeling System (ROMS) produce a general circulation in the Sea of Marmara that is consistent with previous knowledge of the circulation drawn from past hydrographic measurements, with a westward meandering current associated with a recurrent large anticyclone. Additional idealized numerical experiments illuminate the role various dynamics play in determining the Sea of Marmara circulation and pycnocline structure. Both the wind curl and the strait flows are found to strongly influence the strength and location of the main mesoscale features. Large displacements of the pycnocline depth were observed during the sea trials. These displacements can be interpreted as storm-driven upwelling/ downwelling dynamics associated with northeasterly winds; however, lateral advection associated with flow from the Straits also played a role in some displacements.

In situ experimental data and numerical model results are presented for the Ligurian Sea in the northwestern Mediterranean. The Ligurian Sea Air-Sea Interaction Experiment (LASIE07) and LIGURE2007 experiments took place in June 2007. The LASIE07 and LIGURE2007 data are used to validate the Coupled Ocean-Atmosphere Mesoscale Prediction System (COAMPS) 1 developed at the Naval Research Laboratory. This system includes an atmospheric sigma coordinate, nonhydrostatic model, coupled to a hydrostatic sigma-z-level ocean model (Navy Coastal Ocean Model), using the Earth System Modeling Framework (ESMF).A month-long simulation, which includes data assimilation in the atmosphere and full coupling, is compared against an uncoupled run where analysis SST is used for computation of the bulk fluxes. This reveals that COAMPS has reasonable skill in predicting the wind stress and surface heat fluxes at LASIE07 mooring locations in shallow and deep water. At the LASIE07 coastal site (but not at the deep site) the validation shows that the coupled model has a much smaller bias in latent heat flux, because of improvements in the SST field relative to the uncoupled model. This in turn leads to large differences in upper-ocean temperature between the coupled model and an uncoupled ocean model run.

A multidisciplinary project lead by the U.S. Geological Survey is currently studying the fringing reef off southern Molokai, Hawaii, in an effort to characterize the biological structure and geologic variability of coral reef systems. Wave modeling and field observations were utilized to help understand the physical controls on reef morphology and the distribution of coral species. The morphology of the reef crest, which extends roughly 50 km from east to west and up to 1500 m offshore, appears to be primarily controlled by the amount of wave energy impinging on the coastline. Extratropical cyclones and inter-anticyclonic systems crossing the North Pacific during the winter months generate the wave energy regime that appears to dominate the reef. This North Pacific swell generates near-bed orbital velocities greater than 3.0 m/sec and shear stresses greater than 2.5 N/m 2 that inhibit substantial coral development in shallow water (<10 m). The reef is sheltered from these waves by the island of Molokai; however, refraction around the east and west ends of the island cause the reef crest to pinch out roughly 5 km from each end of the island. Where the reef crest merges into the shoreline, more robust high-energy corals and low coral cover typify the fore reef. In contrast, more delicate branching corals characterize the central portion of the reef, which is sheltered from the large North Pacific swell, and up to 80% live coral cover.

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