US-GLOBEC NEP Phase IIIa-CCS: Changing Ocean Conditions in Northern California Current - Effects on Primary Production and Salmon

研究人员将开展一项跨学科研究，研究在为期6年的globecltop期间北加州洋流海洋条件的变化，其中包括厄尔尼诺/拉尼娜转变、亚北极水域的入侵和北太平洋气候制度的转变。他们将专注于综合多个数据集（原位海洋学数据、沿海鲑鱼生存数据以及气候或环境状况指数），以了解水体、洋流、分层、营养物质浓度等的变化如何响应气候强迫，进而影响初级生产和鲑鱼生存。该研究的四个具体目标是：(1)将1997-2003年主要气候事件期间观测到的海洋原位物理和化学条件的变化与初级生产和鲑鱼存活联系起来；(2)确定布兰科角南北上升流区域的海洋原位物理和化学条件、初级生产和鲑鱼存活是否具有相似的年际变率。(3)确定1997-2003年北加州海流系统海洋条件的季节平均值和年际变率是否与早期有历史资料的年代有显著差异；(4)将常用的海洋条件指数与直接影响初级生产和平流的当地原位测量相联系，并寻找改进的指数和测量。这种跨学科海洋学数据与鲑鱼生存和气候指数的综合将促进对沿海上升流生态系统关键过程的知识理解，并提高对有助于鲑鱼生存和气候指数之间统计相关性的动态过程的理解。该研究将对未来东北太平洋地区生态系统监测与管理以及其他沿海上升流地区的研究产生广泛的影响。确定一些对初级生产和鲑鱼幼崽存活至关重要的就地措施或参数，将使利用沿海观测站监测上涌生态系统的健康变得可行和有效。

The investigators will launch an interdisciplinary study of changing ocean conditions in the northern California Current during the 6-year GLOBEC LTOP period, which encompassed an El Nino/La Nina transition, an invasion of Subarctic water and a shift in the climate regime of the North Pacific Ocean. They will focus on synthesizing multiple datasets (in situ oceanographic data, coastal salmon survival data, and indices of climate or environmental status) to learn how changes in water masses, currents, stratification, nutrient concentrations, etc., respond to climate forcing and in turn affect primary production and salmon survival. The four specific objectives of the study are (1) to relate the changing in situ physical and chemical ocean conditions observed during the major climate events of 1997-2003 to primary production and salmon survival, (2) to determine whether in situ physical and chemical ocean conditions, primary production, and salmon survival in the upwelling domains north and south of Cape Blanco have similar interannual variability, (3) to determine whether seasonal averages and interannual variability of ocean conditions in the northern California Current system during the 1997-2003 epoch system were significantly different from earlier epochs for which historical data are available and (4) to relate commonly used indices of ocean conditions to local in situ measures which directly affect primary production and advection and to search for improved indices and measures. This synthesis of interdisciplinary oceanographic data with salmon survival and climate indices will advance intellectual understanding of critical processes in coastal upwelling ecosystems and improve understanding of the dynamic processes that contribute to statistical correlations between salmon survival and climate indices. This study will have broad impacts on the future of ecosystem monitoring and management in the Northeast Pacific, and on future research in other coastal upwelling regions. Identifying a few in situ measures or parameters that are critical for primary production and for salmon smolt survival would make it feasible and efficient to use coastal observing stations to monitor the health of the upwelling ecosystem.