• Directly address specific formulated hypotheses regarding the role of meso-scale circulation and biological patterns in controlling nutrient supply and shelf / coastal production

• Complement process studies and LTOP observations in the CGOA during 2003, and

• Provide a basis for future comparisons of mesoscale processes and patterns in the CGOA and CCS.

Previous announcements have resulted in funded projects to support modeling, retrospective studies, and field observations, including process studies and Long-Term Observation Programs (LTOP). 3-dimensional meso-scale surveys in the CCS are also presently funded, although CGOA mesoscale surveys are not.

NSF has agreed to accept proposals relevant to this U.S. GLOBEC solicitation in order to accomplish the goals of the overall Northeast Pacific Program. Proposals are to be submitted to the Ocean Sciences Division no later than the general proposal deadline of 15 August, 2002. All proposal titles are to start with "GLOBEC-NEP" to distinguish these contributions.

1. The Implementation Plan [U.S. GLOBEC Report No. 17],
2. The descriptions of previously funded CGoA and CCS projects, and
3. A web-based whitepaper [*.pdf] on Mesoscale Surveys in the CGoA.

The Northeast Pacific CGoA study focuses on the continental shelf region south of Seward, Alaska. U.S. GLOBEC field observations of the CGOA began in 1997, with an integrated, multi-investigator, inter-disciplinary, long-term observation program (LTOP) focusing on a main transect line from Seward across the shelf and several other nearby sampling locations [Preliminary Results]. In 2001, detailed observations of physical processes and biological rates [Preliminary Results] were made to examine the factors responsible for seasonal and cross-shelf variability in biological community structure and marine production (from phytoplankton to fish). This announcement solicits proposals to provide information (from spring and summer 2003) on the role of meso-scale circulation and structure in controlling nutrient availability, biological production, and the transfer of energy through the trophic web to juvenile pink salmon and other higher trophic levels. Emphasis is on understanding the conditions that favor rapid growth and survival of juvenile pink salmon and the prey upon which they rely.

The fundamental importance of the meso-scale studies is to provide the basis for comparisons of population processes and their coupling to the physical structure and variability of the environment, and to directly address two of the major goals of the CGOA program:

1. To quantify how physical features in the Coastal Gulf of Alaska impact zooplankton biomass, production, distribution, and the retention and exchange of zooplankton between coastal regions and oceanic waters, with particular emphasis on the euphausiids Euphausia pacifica and Thysanoessa spinifera, and the calanoid copepods Neocalanus and Calanus.

2. To quantify the importance of (a) local primary and secondary production, and (b) imported secondary production (e.g., cross-shelf advection of large-bodied zooplankton [copepods and euphausiids] from deeper offshore waters in spring) in providing habitats that favor rapid growth and high survival of juvenile pink salmon in coastal waters of the Gulf of Alaska.

In addition to addressing posed spatial hypotheses about the importance of complex, perhaps bathymetrically controlled, 3-dimensional flows in determining the quality of the shelf habitat for juvenile salmon, the meso-scale surveys of physical conditions and biological distributions in spring and summer 2003 will augment the less spatially-extensive LTOP observations, which will occur along the Seward Line during all years (1997-2004) of the CGoA study. The surveys will also provide the short-term spatial context for the focused 2003 process studies occurring at a few stations along the Seward Line. The ship-based meso-scale sampling should include the Seward Line, and should encompass the nearshore Alaskan Coastal Current region (driven primarily by freshwater input distributed along the coast, along with downwelling-favorable winds) and extend offshore to the shelf-edge break. It is anticipated that up to one million dollars will be available for field work in 2003 and subsequent analysis and synthesis over the next 1-2 years.