GLOBEC 2000: Gulf of Alaska Long-Term Observation Program

点击翻译按钮获取中文摘要

The PI's will participate in the Gulf of Alaska Long-Term Observation Program (GOA-LTOP) as part of Phase II of the Northeast Pacific (NEP) GLOBEC program. The GOA shelf supports a rich ecosystem that includes many commercially important fisheries. The basis for this productivity is enigmatic for the GOA shelf is deep, forced by downwelling-favorable winds, and fed by a massive nutrient-poor coastal freshwater discharge. Both the winds and the freshwater discharge are intimately linked to the strength and position of the Aleutian Low. The GOA ecosystem experiences substantial physical and biological changes on decadal and inter-annual time scales. Although some of these changes are correlated with various climatic indices a mechanistic understanding of climate change and ecosystem response is unavailable. The generic goal of this LTOP is to understand and quantify temporal (seasonal and interannual) and spatial (cross- and along-shelf) variations in the thermolialine, chemical, and biological pro-perties and relationships of this shelf. This research will support GLOBEC goals by providing the seasonal and interannual context for other concurrent studies, and by providing boundary conditions and data sets for model evaluation. The field effort involves seven, 9-day interdisciplinary cruises/year in the northern GOA. The study area encompasses the 220-km long, Seward Line (sampled in the 1970s) that extends across the shelf and slope and high resolution sampling of the Alaska Coastal Current (ACC), upstream, downstream, and with-in Prince William Sound. The ACC is an important shelf habitat for YOY salmon migrating from nursery areas in the sound and into the GOA.