GLOBEC Gulf of Alaska Projects Selected

The GLOBEC program managers at NSF and NOAA have selected Principal Investigators to be funded in the Northeast Pacific Gulf of Alaska program. Proposals received in response to the announcement exceeded available funds by almost 4:1, so competition for funds was vigorous. Proposals underwent standard mail and panel review and ranking. While details of specific proposals and cruise plans are still not finalized, the roster of PIs has recently been identified.

The Long-Term Observation Program in the Gulf of Alaska will be anchored by Tom Weingartner (University of Alaska) and Tom Royer (Old Dominion University), who will continue their ongoing monitoring work using nine-day cruises in March, April, May, July, August, October, and December. The roving band of LTOPers consists of Weingartner and Royer on physical measurements; Terry Whitledge and Dean Stockwell (University of Alaska) on nutrients, chlorophyll and primary production; Ken Coyle and Russ Hopcroft (University of Alaska) on zooplankton (nets and acoustics); and Lew Haldorson (University of Alaska) on fish. Evelyn Lessard (University of Washington) will cover microzooplankton biomass and grazing rates on the LTOP cruises.

GLOBEC has long championed and supported the development and use of new technologies. In the Gulf of Alaska, Craig Lee and Charlie Eriksen (University of Washington) will be supported to utilize a new, autonomous, telemetering vehicle (the Seaglider) to make continuous, high-resolution sections of the Alaska Coastal Current year-round. The Seaglider measures temperature, conductivity, pressure, chlorophyll fluorescence, dissolved oxygen, and volume scattering; profiling from the surface to within 10 m of the bottom. Horizontal resolution is 2 km. This will augment and extend the temporal and spatial frame of LTOP measurements.

In addition to the collection and sorting of zooplankton and fish that has been ongoing in the Alaska LTOP program, Hopcroft will do copepod incubations to determine growth and reproductive rates, and Haldorson and David Beauchamp (University of Washington) will examine diets, energy content, growth, and condition of salmon, and use spatially-explicit models and bioenergetic models to assess habitat quality and relate salmon condition, growth, bioenergetics, and the environment. Tom Kline (Prince William Sound Science Center) will analyze fish and zooplankton for nitrogen and carbon isotopic ratios to characterize coastal carbon sources isotopically, and relate them to their utilization by fishes.

Additional physical data will come from Phyllis Stabeno (Pacific Marine Environmental Lab), who will deploy moorings from April/May 2001 through September 2004. Instrumentation will include meteorological instruments, temperature recorders, SEACATs, ADCP, current meters, fluorometers, nitrate meters, and acoustic transducers. Drifters will also be deployed to map mean currents and continuity of flow in the Alaska Coastal Current, and identify mesoscale features on the shelf and shelf break. Assisting Phyllis in this deployment and interpretation will be Calvin Mordy (Pacific Marine Environmental Laboratory) for nutrients; and Jeff Napp (Alaska Fisheries Science Center, Seattle) and Van Holliday (BAE Systems) for zooplankton acoustics. Data from these moorings and drifters will be used to help determine the processes that control circulation and transport of nitrate and zooplankton in the study area, assess the relationship between physical forcing and cross-shelf fluxes of inorganic nutrients, and construct a time series of zooplankton biomass and size structure to link with physical processes.

Providing a larger-scale view of the region in one snapshot during the year will be an augmentation of the National Marine Fisheries Service Ocean Carrying Capacity surveys, led by Jack Helle and Ed Farley (Alaska Fisheries Science Center, Auke Bay), Ned Cokelet and Phyllis Stabeno (Pacific Marine Environmental Laboratory), and Anne Hollowed (Alaska Fisheries Science Center, Seattle). This survey will occur during July-August in years 2001 - 2004. Physical measurements will include ADCP, temperature and salinity taken while the ship is underway to at least 50 shelf stations and 20 slope stations, where juvenile salmon and zooplankton will be sampled. The physical-biological data collected will allow these investigators to help identify physical factors that might influence juvenile salmon spatial distribution, migration, growth, and condition; and develop a conceptual model of juvenile salmon survival.

Coordinated zooplankton process cruises will occur in early spring, mid-spring, and summer to quantify copepod egg production and viability, and relate these to grazing and the microplankton community. Jeff Napp will measure natural variability in copepod egg production rates and viability, and relate egg production rates to microplankton abundance and composition (in association with Suzanne Strom, Western Washington University). Strom and Mike Dagg (Louisiana Universities Marine Consortium) will measure microplankton abundance and composition, rates of microzooplankton herbivory, and rates of Neocalanus spp. grazing on microzooplankton and phytoplankton. These zooplankton process cruises are planned to take place in four different coastal physical regimes to study how variation in the physical environment dictates production levels and food web structure in the Gulf of Alaska.

Modeling will continue to provide larger-scale context for the field data. Dale Haidvogel (Rutgers University), Al Hermann (Pacific Marine Environmental Lab), and Sarah Hinkley (Alaska Fisheries Science Center) will refine a spatially nested ocean circulation model for the Gulf of Alaska, and link it to NPZ modeling. They also propose assimilation of the data collected in the field program, and development of web-based 3-D model visualization. Jim Overland (Pacific Marine Environmental Lab) and Nick Bond (University of Washington) will model atmospheric forcing of the Alaska Coastal Current by both a large-scale, basin-wide component and a local, coastal zone component. Validation of the model will be done using data from the Stabeno moorings. Ultimately, this effort will explore how interannual and interdecadal changes in atmospheric forcing are communicated to the ACC. All of these modeling efforts relate to similar efforts in the GLOBEC NEP California Current System program.

Retrospective projects will provide a glimpse into the past, and a temporal context for the five years of the CGOA program. Mark Ohman (Scripps Institution of Oceanography) will continue his work funded under NEP Phase 1 to analyze zooplankton population structure in light of measures of atmospheric and oceanic forcing, especially focusing on the 1976-1977 climate regime shift. Bill Heard (NMFS Alaska Fisheries Science Center, Auke Bay Lab) will analyze archived and current collections of salmon scales and correlate growth to biophysical parameters of the environment, and to local abundances of salmon year classes. This project is an enhancement of the Southeast Alaska Coastal Monitoring program of NMFS.

Also considered by this panel was a group of proposals for microzooplankton measurements in the GLOBEC NEP California Current System (CCS) program. Barry and Ev Sherr (Oregon State University) were chosen to analyze microzooplankton abundance, biomass, and general taxonomic composition in conjunction with the CCS LTOP cruises.

Congratulations to all the successful proposers, and GLOBEC looks forward to their expertise, experience, and enthusiasm in the Gulf of Alaska program.