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

缅因湾位于西北大西洋。其水域是具有重要经济意义的大西洋鳕鱼和贝类产业的所在地。 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，该地区的环境长期记录很少，因此很难准确判断这些变化何时开始以及有多少与人类活动有关。 在该项目中，来自三所大学的研究人员团队将通过测量当地蛤和藻类的年度生长带来构建该区域环境 250 年的历史。 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如何影响环境，并将其与温室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委员会关于如何更好地管理该地区的政策决策提供信息。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，利用两种类型的高分辨率海洋气候档案（蛤和壳状珊瑚藻）中的地球化学代理来重建海洋条件的过去变化，包括缅因湾过去 250 年的近表面海水温度、盐度和 pH 值。蛤壳和长寿海洋钙化物骨骼的年度生长带中保存的地球化学指纹（或代理）已被广泛用作过去海洋状况的档案。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工业革命之前西北大西洋（包括缅因湾）几个百年的、每年解析的、绝对日期的海洋变化数据集，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颖代理的新数据与现有水文记录相结合，将描述源水随时间推移进入缅因湾的相对贡献，以更好地了解缅因湾内变化的驱动因素。因此，了解缅因湾过去的海洋变化对于预测未来变化的可能程度和幅度以及规划保护生态系统和渔业至关重要。结果将通过出版物、会议演示、指导计划、课程作业以及地区学校、博物馆和科学中心的外展活动向科学和非科学受众广泛传播。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力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.