Collaborative Research: Interannual Variability of Coastal Phytoplankton Blooms in the Gulf of Maine and Their Relationships to Local and Remote Forcings

该项目的目的是探索远程气候为基础的强迫与本地强迫的相互作用，影响浮游植物水华在沿海和大陆架地区的耦合生物物理模型。浮游植物水华动态是海洋中生物-物理相互作用的一个典型例子（Gran和Braarud，1935年; Sverdrup，1953年）。然而，在多尺度生物和物理过程相互作用的沿海和陆架海，确定控制浮游植物水华年际变化的主导过程仍然是一个挑战。非结构化网格，有限体积，沿海海洋模式（FVCOM，建立在GLOBEC乔治银行计划）桥梁的多尺度物理过程的缅因州的海湾，包括本地和远程强迫。12年的预测模拟和同化实验产品，仔细比较/验证与实地测量，提供了一个独特的背景和工具，探索生态系统动力学的年际变化在缅因州的海湾。该项目将研究春季和秋季海湾浮游植物水华的动态与当地和远程强迫之间的关系。一个具体的重点是变化斯科舍陆架水和斜坡水流入。将进行一系列数值实验，以测试长期存在的和最近提出的假设，包括北大西洋涛动的影响，因为它影响温暖的斜坡水与拉布拉多斜坡水动力学，这反过来又影响营养通量的缅因州湾和垂直通量之间的表面和深层沃茨。地表水清新（有关斯科舍陆架水流入，反过来认为是受全球变暖的影响）的水柱，冬季对流的垂直密度结构的影响，因此，开花的时间/幅度，也将得到解决。面向过程的耦合生物和物理模型实验将集中在日期丰富的时期1998-2001年，当明显的大规模强迫条件发生。提供新的见解，大规模强迫对沿海海洋生态系统的动态和生产力的影响，将是我们对浮游植物水华动态的理解，这一直是传统上集中在本地强迫和季节性变化的一个重大进步。该项目将提供1995-2006年耦合模型每小时物理和生物输出的网上公开档案，并制作一个经过测试的耦合生物物理模型系统，可用于缅因州湾和其他沿海海洋其他正在进行的（如ECOHAB）和未来的生态系统研究。UMASSD-WHOI正在开发的基于网络的海洋预报模型系统将直接受益于这一项目，帮助优化海洋观测站的设计，并帮助塑造相互依赖的模型观测系统的未来。结果将广泛传播到一般研究，本科和研究生教育社区，K-12机构，并利用调查机构的现有基础设施，通过基于网络的服务器向感兴趣的公众提供。基于Web的用户将能够访问项目描述，科学成果，模型输入和输出档案，动画的各种物理和生物领域，等与新贝德福德SEALAB海洋科学教育中心和WHOI/UMASS COSEE计划的合作将促进与K-12教师和学生以及国内外公众的沟通。

The aim of this project is to explore the interaction of remote climate based forcing with local forcing to impact phytoplankton blooms in coastal and shelf regions with a coupled biological-physical model. Phytoplankton bloom dynamics are a classic example of biological-physical interactions in the ocean (Gran and Braarud, 1935; Sverdrup, 1953). Yet it is still a challenge to identify the dominant processes controlling the interannual variability of phytoplankton blooms in coastal and shelf seas where multiple-scale biological and physical processes interact. The unstructured-grid, finite-volume, coastal ocean model (FVCOM, built within the GLOBEC Georges Bank Program) bridges the multi-scale physical processes of the Gulf of Maine and includes both local and remote forcing. Twelve years of prognostic simulation and assimilation experiment products, with careful comparison/validation with field measurements, provide a unique background and tools with which to explore the interannual variability of ecosystem dynamics in the Gulf of Maine. This project will examine relationships between the dynamics of spring and fall phytoplankton blooms in the Gulf and local and remote forcing. A specific focus is the variability Scotian Shelf Water and Slope Water inflows. A series of numerical experiments will be conducted to test long-standing and recently-proposed hypotheses, including the impact of the North Atlantic Oscillation as it influences Warm Slope Water versus Labrador Slope Water dynamics, which in turn affect nutrient fluxes to the Gulf of Maine and vertical fluxes between surface and deep waters. The influence of surface water freshening (related to Scotian Shelf Water inflow, in turn believed to be affected by global warming) on the vertical density structure of the water column, winter convection, and consequently, the timing/magnitude of blooms, will also be addressed. The process-oriented coupled biological and physical model experiments will focus on the date-rich period 1998-2001 when pronounced large-scale forcing conditions occurred. Providing new insights into the influence of large-scale forcing on the dynamics and productivity of coastal ocean ecosystems will be a significant advance in our understanding of phytoplankton blooms dynamics, which has been traditionally focused on local forcing and seasonal changes. The project will provide a web-based open archive of the 1995-2006 coupled model hourly physical and biological output, and produce a tested coupled biological-physical model system available for other ongoing (e.g. ECOHAB) and future ecosystem studies in the Gulf of Maine and other coastal oceans. The web-based ocean forecast model system being developed by UMASSD-WHOI will benefit directly from this project by helping to optimize the design of ocean observatories and help shape the future of interdependent model-observing systems.Broader Impacts: Results will be broadly disseminated to the general research, undergraduate and graduate education communities, K-12 institutions, and to the interested public through web-based servers using existing infrastructure at the investigators' institutions. Web-based users will be able to access project description, scientific results, model input and output archives, animations of various physical and biological fields, etc. Collaboration with the New Bedford SEALAB Marine Science Education Center and the WHOI/UMASS COSEE program will foster communication with K-12 teachers and students and the public both nationally and internationally.