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大本营。但最近这种环境的变化对生态系统和商业渔业构成了威胁。然而，这一地区只有几个长期的环境记录，因此很难准确地判断这些变化是从什么时候开始的，以及有多少与人类活动有关。在这个项目中，来自三所大学的一组研究人员将通过测量当地文蛤和藻类的年生长带来构建该地区250年的环境历史。这些生长带上的化学指纹将被用来确定水温、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，并将这些变化与温室气体全球变暖造成的变化进行比较。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。具体地说，该小组将使用两种高分辨率海洋气候档案(文蛤和硬壳珊瑚藻类)中的地球化学替代物多管齐下，重建过去250年来海洋条件的变化，包括缅因湾近地表海水的温度、盐度和pH值。保存在蛤壳和长寿海洋钙化动物骨骼的年生长带中的地球化学指纹(或代用品)被广泛用作过去海洋状况的档案。可以从文蛤和硬壳珊瑚藻类的生长带中提取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，拟议的研究可能会产生工业革命前西北大西洋，包括缅因湾的几个百年来、每年分辨的、绝对过时的海洋变异性数据集，这些数据集将被用来评估大西洋经向翻转环流和其他气候强迫对观测变化的作用。通过将来自传统和新型替代指标的新数据与现有水文记录相结合，将表征源水随时间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程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、课程作业和地区学校、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.