Collaborative Research: Using multi-proxy paleo data to constrain natural and anthropogenic hydrographic variability in the Gulf of Maine System over the last 250 years

缅因湾位于大西洋西北部。它的水域是经济上重要的大西洋鳕鱼和贝类产业的家园。但最近这种环境的变化对生态系统和商业捕鱼业构成了威胁。然而，该地区只有很少的长期环境记录，因此很难准确地说出这些变化是何时开始的，以及与人类活动的关系有多大。在这个项目中，来自三所大学的一个研究小组将通过测量当地蛤蜊和藻类的年生长带来构建一个250年的区域环境历史。这些生长带中的化学指纹将用于确定水温、盐度、生物生产力和pH条件。这使得科学家能够研究自然变化是如何影响环境的，并将这些变化与温室效应引起的全球变暖进行比较。这些信息将为新成立的缅因州气候委员会就如何更好地管理这一地区做出政策决定提供信息。拟议的工作还将支持对早期职业科学家的培训，扩大对科学项目的参与，并支持本科生的研究机会。具体来说，该团队将采用多管齐下的方法，在两种高分辨率的海洋气候档案（蛤蜊和甲壳珊瑚藻类）中使用地球化学代理来重建过去海洋条件的变化，包括过去250年来缅因湾近地表海水的温度、盐度和pH值。保存在蛤壳和长寿命海洋钙化动物骨骼年生长带中的地球化学指纹（或代用物）已被广泛用作过去海洋状况的档案。从蛤蜊和甲壳珊瑚藻的生长带中采集离散的碳酸钙层，进行地球化学分析，生成代理档案记录。这些对过去环境条件的重建填补了仪器记录之前的数据空白。因此，拟议的研究将有可能产生几个百年一次的、每年确定的、确定日期的西北大西洋海洋变化数据集，包括工业革命之前的缅因湾，这些数据集将用于评估大西洋经向翻转环流和其他气候强迫对观测到的变化的作用。通过将来自传统和新型代用物的新数据与现有水文记录相结合，将表征源水随时间对缅因湾的相对贡献，以更好地理解缅因湾内变化的驱动因素。因此，了解缅因湾过去的海洋学变化对于预测未来变化的可能程度和幅度以及制定保护生态系统和渔业的计划至关重要。研究结果将通过出版物、会议报告、指导计划、课程作业以及地区学校、博物馆和科学中心的推广活动，广泛传播给科学和非科学受众。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The Gulf of Maine is located in the Northwestern Atlantic Ocean. Its waters serve as home to the economically important Atlantic Cod and shellfish industry. But recent changes to this environment pose a threat to the ecosystem and the commercial fishing industry. However, only a few long-term records of the environment exist in this area making it difficult to tell exactly when these changes started and how much is related to human activities. In this project, a team of researchers from three universities will construct a 250-year history of the regional environment by measuring yearly growth bands in local clams and algae. Chemical fingerprints in these growth bands will be used to determine the water temperature, salinity, biological productivity and pH conditions. This allow scientists to study how natural changes have affected the environment and compare these to changes caused by greenhouse global warming. This information will inform policy decisions of the newly-formed Maine Climate Council on how to better manage this area. The proposed work will also support training for early career scientists, broaden participation in science programs, and support undergraduate research opportunities. Specifically, the team will use a multi-pronged approach using geochemical proxies in two types of high-resolution marine climate archives (clams and crustose coralline algae) to reconstruct past changes in oceanographic conditions, including near surface seawater temperatures, salinity, and pH in the Gulf of Maine through the last 250 years. Geochemical fingerprints (or proxies) preserved in the annual growth bands of clam shells and skeletons of long-lived marine calcifiers have been used extensively as archives of past ocean conditions. Discrete calcium carbonate layers can be sampled from the growth bands of clams and crustose coralline algae for geochemical analysis, generating proxy archive records. These reconstructions of past environmental conditions fill data gaps prior to instrumental records. Hence, the proposed research will potentially yield several multi-centennial, annually-resolved, absolutely-dated datasets of oceanographic variability in the Northwestern Atlantic, including the Gulf of Maine, prior to the Industrial Revolution, which will be used to evaluate the role of Atlantic meridional overturning circulation, and other climate forcings, on observed changes. By combining new data derived from traditional and novel proxies with existing hydrographic records, the relative contributions of source waters into the Gulf of Maine through time will be characterized to better understand the drivers of variability within the Gulf of Maine. Understanding past oceanographic variability in the Gulf of Maine is therefore critical for predicting the likely extent and magnitude of future change, and for planning to safeguard ecosystems and fisheries. Results will be widely disseminated to science and non-science audiences through publications, conference presentations, mentoring programs, coursework, and outreach activities at area schools, museums, and science centers.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.