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Author Posting. © American Meteorological Society 2005. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Atmospheric and Oceanic Technology 22 (2005): 1267–1281, doi:10.1175/JTECH1760.1., The focus of this paper is on the development of methodology for short-term (1–3 days) oceanic bioluminescence (BL) predictions and the optimization of spatial and temporal bioluminescence sampling strategies. The approach is based on predictions of bioluminescence with an advection–diffusion–reaction (tracer) model with velocities and diffusivities from a circulation model. In previous research, it was shown that short-term changes in some of the salient features in coastal bioluminescence can be explained and predicted by using this approach. At the same time, it was demonstrated that optimization of bioluminescence sampling prior to the forecast is critical for successful short-term BL predictions with the tracer model. In the present paper, the adjoint to the tracer model is used to study the sensitivity of the modeled bioluminescence distributions to the sampling strategies for BL. The locations and times of bioluminescence sampling prior to the forecast are determined by using the adjoint-based sensitivity maps. The approach is tested with bioluminescence observations collected during August 2000 and 2003 in the Monterey Bay, California, area. During August 2000, BL surveys were collected during a strong wind relaxation event, while in August 2003, BL surveys were conducted during an extended (longer than a week) upwelling-favorable event. The numerical bioluminescence predictability experiments demonstrated a close agreement between observed and model-predicted short-term spatial and temporal changes of the coastal bioluminescence., This work has been supported by the Ocean Optics and Biology and Physical Oceanography Programs of the Office of Naval Research. Shulman’s support is through the NRL “Use of a Circulation Model to Enhance Predictability of Bioluminescence in the Coastal Ocean” project sponsored by the Office of Naval Research.

Author Posting. © American Meteorological Society 2005. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Atmospheric and Oceanic Technology 22 (2005): 1267–1281, doi:10.1175/JTECH1760.1., The focus of this paper is on the development of methodology for short-term (1–3 days) oceanic bioluminescence (BL) predictions and the optimization of spatial and temporal bioluminescence sampling strategies. The approach is based on predictions of bioluminescence with an advection–diffusion–reaction (tracer) model with velocities and diffusivities from a circulation model. In previous research, it was shown that short-term changes in some of the salient features in coastal bioluminescence can be explained and predicted by using this approach. At the same time, it was demonstrated that optimization of bioluminescence sampling prior to the forecast is critical for successful short-term BL predictions with the tracer model. In the present paper, the adjoint to the tracer model is used to study the sensitivity of the modeled bioluminescence distributions to the sampling strategies for BL. The locations and times of bioluminescence sampling prior to the forecast are determined by using the adjoint-based sensitivity maps. The approach is tested with bioluminescence observations collected during August 2000 and 2003 in the Monterey Bay, California, area. During August 2000, BL surveys were collected during a strong wind relaxation event, while in August 2003, BL surveys were conducted during an extended (longer than a week) upwelling-favorable event. The numerical bioluminescence predictability experiments demonstrated a close agreement between observed and model-predicted short-term spatial and temporal changes of the coastal bioluminescence., This work has been supported by the Ocean Optics and Biology and Physical Oceanography Programs of the Office of Naval Research. Shulman’s support is through the NRL “Use of a Circulation Model to Enhance Predictability of Bioluminescence in the Coastal Ocean” project sponsored by the Office of Naval Research.

The Oregon Coastal Transition Zone (OCTZ) extends several hundred kilometers offshore where shelf flows interact with the northern California Current. A primitive-equation numerical ocean model is used to study the upwelling circulation in this region from May 1 to November 1, 2001. This OCTZ model obtains initial and boundary conditions from a larger-scale model of the California Current System and forcing from a regional atmospheric model product. The model results are compared with extensive in situ and remotely sensed data, and the model is found to provide a useful representation of flows both over the shelf and in the broader OCTZ. Simulation of coastal sea level and shelf currents over the complex topography of the central Oregon coast is improved quantitatively relative to previous regional models. A particularly significant qualitative improvement is realistic representation of coastal jet separation and eddy formation offshore of Cape Blanco. A three-dimensional Lagrangian analysis of water parcel displacement shows that the surface waters inshore of the separated jet are upwelled from near the bottom along the shelf as far north as 45.5 degrees N. A large eddy, which incorporates some of this upwelled water and carries it farther westward, forms offshore in the late summer. Ensemble simulations point toward a distinction between the strongly deterministic response to wind forcing over the shelf, and more unstable, less predictable jet separation and offshore eddy formation processes in the region near Cape Blanco., Prepared in collaboration with the Oceanography Division, Naval Research Laboratory, Stennis Space Center, MS. Submitted to Journal of Geophysical Research; final version published in v114 nC2 article C02010.. Supported through the National Ocean Partnership Program. The original document contains color images.

The Naval Oceanographic and Atmospheric Research Laboratory (NOARL) one active layer reduced gravity global ocean model is running in real time at the Fleet Numerical Oceanography Center forced by the Navy Operational Global Atmospheric Prediction System (NOGAPS) wind fields. The model has a resolution of .5 deg x .7 deg (lat., long.) and depicts a few eddies but it is basically non eddy-resolving; it does depict most of the major current systems and large- scale fronts. In addition, the model clearly shows evidence of an El Nino-like event in the equatorial Pacific Ocean during 1989-1990. (edc), Original contains color plates: All DTIC and NTIS reproductions will be in black and white. Prepared in collaboration with Jaycor, Stennis Space Center, MS.

The seasonal and interannual variability of the bay of Bengal Western Boundary Current are examined using a one active layer, primitive equation, reduced-gravity model of the entire Indian Ocean north of 30 deg South. The model is forced by the hellerman and Rosenstein wind stress climatology as well as mean monthly wind stress values derived from the National Meteorological Center 1000 mb forecast winds for the period 1981-1987. The numerical simulations yield a seasonally reversing western boundary current in the Bay of Bengal with maximum northward transport in February and southward transport from June to October. The simulation forced by the NWC winds from 1981 to 1987 yields a maximum wintertime transport in February, 1985 which coincides with the only period for which Legeckis (1987) was able to observe the current form NOAA satellite IR imagery. The numerical results show that the Bay of Bengal Western Boundary Current is primarily forced by the wind stress curl. The relationship between the flow off the east coast of Sri Lanka and the Western boundary current to the north is also examined.