Bottom temperatures data collected at all stations of the research survey since 1963. [ Reference: PICES Scientific Report No. 18 2001, Proceedings of the PICES/CoML/IPRC Workshop on "Impact of Climate Variability on Observation and Prediction of Ecosystem and Biodiversity Changes in the North Pacific", http://www.pices.int/publications/scientific_reports/Report18/default.aspx. ]

The diurnal cycle in the heat budget of the upper equatorial Pacific Ocean is studied using 26 days of special high-resolution oceanographic and meteorological observations from a current meter mooring at 0°, 140°W. The focus is on the turbulent heat fluxes at the base of the mixed layer, which are calculated as a residual in the mean diurnal heat budget. The inferred downward heat flux at the base of the mixed layer is ~150 W m, averaged over the mean diurnal cycle, and ranged from near zero in the morning and early afternoon to ~200 W m during the late afternoon until dawn. The magnitude and phasing of the mean diurnal cycle were similar for different definitions of the mixed layer depth. The inferred residual turbulent fluxes were used also to estimate the mean diurnal cycles in vertical eddy diffusivity and turbulent dissipation rate. These turbulence parameters and the heat fluxes from which they were derived have magnitudes that are broadly consistent with those estimated previously from direct microstructure measurements.

This model was designed to determine the minimum state variables needed to represent a generic Nutrient-Phytoplankton-Zooplankton (NPZ) marine ecosystem model for the North Pacific. Ecosystem fluxes are tracked in units of both nitrogen and silicon. Carbon flux process equations have been added recently. [ Reference: PICES Scientific Report No. 18 2001, Proceedings of the PICES/CoML/IPRC Workshop on "Impact of Climate Variability on Observation and Prediction of Ecosystem and Biodiversity Changes in the North Pacific", http://www.pices.int/publications/scientific_reports/Report18/default.aspx. ]

The investigator will use numerical models of increasing sophistication to study the Japan/East Sea dynamics, and will compare the results with the intensive field program. Short Work Statement: The investigator will 1) Write up results from the basic Navy Layered Ocean Model (NLOM) runs; 2) Add investigations using the Miami Isopycnal Coordinate Ocean Model (MICOM); and 3) Begin joint development (with Prof. Rainer Bleck, University of Miami) of a new hybrid isopycnal/sigma (generalized) coordinate ocean model for marginal seas to maintain high vertical resolution over the shelf and in the mixed layer.International Collaborator: Dr. Dong-Kyu Lee (Pusan National University, Korea). Model/drifter comparisons.U.S. Office of Naval Research (ONR) supported research in the Japan/East Sea (JES) during 1998-2000. JES website URL: http://sam.ucsd.edu/onr_jes/onr_jes.html

Two cores for shipboard incubations from each of 20 to 30 stations during July and September 1999, using the HAPS benthic corer. An NPMR project

Subsurface mooring data from St. George Island, Bering Sea: Station St. George Island 3. Data were collected from 1994 through 2004. Sampled months varied through the years but were usually during April. Velocity data were collected at various depths throughout the years using instruments such as ADP. 101m was the maximum bottom depth.

Deep helium measurements for CGC-91 section (also named WOCE P1) along 152°W. Hydrothermal activity produces a helium plume which can be traced for thousands of kilometers.

Deep helium measurements for CGC-91 section (also named WOCE P1) along 135°W. Hydrothermal activity produces a helium plume which can be traced for thousands of kilometers.

This project addresses the need to integrate top trophic-level predators into interdisciplinary mesoscale and fine-scale process studies of middle trophic levels in the southeast Bering Sea. In collaboration with physical, chemical and biological sampling within the Fisheries-Oceanography Coordinated Investigations (FOCI) and the Midwater Assessment and Conservation Engineering Program (MACE), our survey will provide data to define trophic linkages between middle and upper trophic levels, specifically cetaceans, contributing to effects on community structure and function. Results will define top-down and bottom-up interactions, especially in regard to euphausiids (Thysanoessa inermis and T. raschii) and copepods (e.g., Neocalanus cristatus, Neocalanus plumchrus, and Calanus marshallae) which are important forage for upper trophic level predators. Information on the spatial distributions of whales, and estimates of feeding rates, relative to interannual variability in the productivity and physical forcing in the system, will be used to estimate rates of energy transfer upward from middle trophic levels. Models of trophic interactions and carbon flow within the systems will greatly benefit from these data. Predation may also be a factor that explains swarming and schooling of zooplankton and fish, thus further explaining discontinuities of prey distributions. Finally, in addition to the mesoscale survey, we will focus specific sampling and foraging aggregations of whales, which act as natural integrative plankton recorders. Our survey defines mesoscale variability in zooplankton biomass across the shelf from the shelf-edge to the Inner Front. From the bottom-up perspective, we propose to test the hypothesis that physical processes and variation in prey density do not affect the occurrence patterns of top trophic level predators in the southeast Bering Sea shelf; or that there is no threshold of prey density that can just be reached before the distribution of predators is affected. Alternately, from the top-down perspective, we hypothesize that average swarm/school characteristics, as assessed by acoustic and net sampling (i.e. size, depth, density, shape), remain the same regardless of densities and behavior of predators in the vicinity. [ An NPMR project ] [ Reference: Tynan, C.T. 2004. Cetacean populations on the southeastern Bering Sea shelf during the late 1990s: Implications for decadal changes in ecosystem structure and carbon flow. Marine Ecology Progress Series (in press) ]

Water temperature data were collected in the Bering Sea during MIZEX West, OCSEAP, and FOCI deployments, from 1977 to 1989. These data are stored on 74 disk files (8.1 MB) at the Pacific Marine Environmental Laboratory in Seattle, Washington. NOAAServer Codes: [L 75 56 -160 -180] ; nodateline