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

缅因州湾位于大西洋西北部。它的沃茨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，该地区只有少数长期的环境记录，因此很难确切地说出这些变化是何时开始的，以及有多少与人类活动有关。 在这个项目中，来自三所大学的研究人员将通过测量当地蛤蜊和藻类的年度生长带来构建一个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。这使科学家们能够研究自然变化如何影响环境，并将其与温室气体全球变暖引起的变化进行比较。 这些信息将为新成立的缅因州气候理事会关于如何更好地管理这一领域的政策决定提供信息。拟议的工作还将支持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。具体而言，该团队将使用两种类型的高分辨率海洋气候档案（蛤蜊和甲壳珊瑚藻）中的地球化学代理的多管齐下的方法来重建过去海洋条件的变化，包括近地表海水温度，盐度和过去250年来缅因州海湾的pH值。保存在蛤蜊壳的年生长带和长寿的海洋钙化物骨骼中的地球化学指纹（或代理）已被广泛用作过去海洋条件的档案。可以从蛤和壳状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，生成代用档案记录。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，拟议的研究将可能产生几个多世纪，每年解决，绝对日期的数据集的海洋变化在西北大西洋，包括缅因州湾，工业革命之前，这将被用来评估大西洋纬向翻转环流的作用，和其他气候强迫，对观测到的变化。通过将来自传统和新型代理的新数据与现有水文记录相结合，将描述源沃茨随时间对缅因州湾的相对贡献，以更好地了解缅因州湾内变化的驱动因素。因此，了解缅因州海湾过去的海洋变化对于预测未来变化的可能范围和幅度以及规划保护生态系统和渔业至关重要。研究结果将通过出版物、会议报告、指导计划、课程以及地区学校、博物馆和科学中心的外展活动广泛传播给科学和非科学受众。该奖项反映了NSF的法定使命，并被认为值得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来支持。

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.