U.S. GLOBEC: NWA Georges Bank - Processes Controlling Abundance of Dominant Copepod Species on Georges Bank: Local Dynamics and Large-Scale Forcing

生物海洋学的一个基本目标是了解潜在的生物-物理相互作用如何决定海洋生物的丰度。对于动物种群来说，众所周知，在生命早期阶段控制生存的因素（即招募）是成年种群规模的重要决定因素，但由于模型和数据的限制，理解这些过程一直很困难。数值模拟的最新进展，加上新的3D数据集，为研究控制浮游动物种群规模的生物物理过程提供了独特的机会。本项目使用现有的最先进的生物/物理数值模型（FVCOM）和最近处理过的来自乔治滩GLOBEC项目的大型3D数据集，进行理想化和现实的数值实验，探索控制乔治滩主要浮游动物物种空间格局季节性演变的详细机制。关于河岸上占优势的桡足类物种种群如何维持的假设，包括局部动态和大规模强迫，将进行研究。一个具体的目标是确定观测到的每个物种的特征季节和空间格局（长期和年际）是否可以从其特征生活史特征和物理运输之间的相互作用中预测。将研究桡足类种群在多大程度上受食物供应（自下而上）或捕食（自上而下）过程的控制，包括暖坡水对拉布拉多坡水（nao依赖）对东北航道养分流入以及随后的上升流和河岸生物增强的影响。将通过控制来自特定来源地区的移民来研究河岸本身和缅因湾每个物种种群的自我可持续性。大尺度强迫，包括NAO和灾难性全球变暖（如极地冰完全融化），将通过在边界强迫模式，使用基于盆地尺度数据和同时进行的盆地尺度模拟工作的情景，明确地进行检验。该模型研究将为局部和大规模过程控制海洋浮游动物丰度的作用提供新的见解。研究的优势桡足类物种包括该地区鳕鱼和黑线鳕幼虫的主要猎物小物种，从而为并行幼虫鱼模型研究提供重要信息。这种详细的、面向过程的、带有边界强迫的区域尺度模拟将为与整个海洋盆地的模式整合奠定基础。由此产生的模型将成为GLOBEC Georges Bank项目的遗产，为了解当地和大规模强迫如何相互作用以控制海洋浮游生物的生产提供一个强大的新工具。拟议工作的结果将通过使用现有基础设施的网络服务器广泛传播给一般海洋学界、渔业、K-12机构和广大人口。基于网络的用户将能够访问模型结果，并使用选定的参数设置运行模型，以在选定的气候强迫情景下获得对洋流、水文和浮游生物丰度模式的预测。与WHOI/马萨诸塞大学COSEE项目的合作将促进与K12学生和国内外公众的交流。

A fundamental goal of Biological Oceanography is to understand how underlying biological-physical interactions determine abundance of marine organisms. For animal populations, it is well known that factors controlling survival during early life stages (i.e., recruitment) are strong determinants of adult population size, but understanding these processes has been difficult due to model and data limitations. Recent advances in numerical modeling, together with new 3D data sets, provide a unique opportunity to study the biological-physical processes controlling zooplankton population size. This project uses an existing state-of-the-art biological/physical numerical model (FVCOM) together with the recently processed large 3D data set from the Georges Bank GLOBEC program to conduct idealized and realistic numerical experiments that explore the detailed mechanisms controlling seasonal evolution of spatial patterns in dominant zooplankton species on Georges Bank. Hypotheses that address how dominant copepod species populations are maintained on the bank, including local dynamics and large-scale forcing will be examined. A specific goal is to determine whether the observed characteristic seasonal and spatial pattern of each species (long-term and inter-annual) is predictable from the interaction between its characteristic life-history traits and physical transport. The extent to which the copepod populations are controled by food-availability (bottom-up) or predation (top-down) processes will be examined, including the influence of Warm Slope Water versus Labrador Slope Water (NAO-dependent) on nutrient influx through the Northeast Channel and subsequent upwelling and biological enhancement on the bank. Self-sustainability of each species population on the bank itself and in the Gulf of Maine will be studied by controlling immigration from specific source regions. Large-scale forcing including NAO and catastrophic global warming (e.g. complete polar ice melt) will be examined explicitly by forcing the model at the boundaries, using scenarios based on basin-scale data and from concurrent basin-scale modeling efforts. This modeling study will provide new insights into the role of local and large-scale processes controlling zooplankton abundance in the ocean. The dominant copepod species to be studied include small species that are the dominant prey for larval cod and haddock in this region, thus providing critical information for concurrent larval fish modeling studies. This detailed, process-oriented, regional-scale modeling with boundary forcing will lay the groundwork for integration with models of the entire ocean basin. The resulting model will be a legacy of the GLOBEC Georges Bank program by providing a powerful new tool for understanding how local and large-scale forcing interact to control plankton production in the sea. Results of the proposed work will be broadly disseminated to the general oceanographic community, the fishing industry, K-12 institutions, and to the population at large, through web-based servers using existing infrastructure. Web-based users will be able to access model results and run the model using chosen parameter settings to obtain predictions of currents, hydrography, and plankton abundance patterns given selected climate forcing scenarios. Collaboration with the WHOI/UMASS COSEE program will foster communication with K12 students and the public both nationally and internationally.