Collaborative Research:Extracting Multi-century Low-latitude Sea Surface Temperatures from Coral Skeletons Using Replicated Records of Annual Growth: Method Refinement&Application

合作研究：利用年度生长的复制记录从珊瑚骨骼中提取多个世纪的低纬度海面温度：方法改进

• 批准号: 1211106
• 负责人: Braddock Linsley
• 金额: $ 7.92万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1211106&HistoricalAwards=false
• 关键词: Collaborative; Research; Extracting; Multi; century

Proxy reconstructions of global temperatures over the past 1000 years provide a context for understanding recent warming trends and allow better estimates of the contribution of anthropogenic (greenhouse gas) forcing to global climate change. Data compiled mostly from high latitude tree ring records suggest that the late 20th century was the warmest period of the last millennium. Nevertheless, the uncertainties associated with these estimates are significant, especially during the period known as the Medieval Warming which ended ~700 years ago. Temperature changes at the earth?s surface follow most closely those of the global tropics, which are 75% ocean; yet few datasets that span the last 1000 years exist from the low latitude oceans. In order to improve global temperature reconstructions and to reduce uncertainties, well-replicated records of sea surface temperature (SST) from the low-latitude oceans are urgently needed. Massive long-lived corals, which accrete calcium carbonate skeleton in annual bands like growth rings on a tree, have the potential to provide this information. The PIs have recently applied a method of reconstructing annual SST that takes advantage of the demonstrated relationship between the skeletal growth of corals and water temperature. In multiple records generated from 3 coral species, coral growth captures between 50-60% of the SST variability in the instrumental record, on interannual and longer timescales. Applying the method to a ~440-year long slow-growing coral collected from the Bahamas suggests that SSTs were within error of modern ~ AD1550, that Little Ice Age SSTs were about 1ºC cooler than today and that there is a strong anthropogenic signal in the SSTs of the last 50 years. The PIs will build on this initial work, focusing on refining the method of extracting SST from coral growth records and applying it to generate multi-century long proxy SST records for the low-latitude Atlantic and Pacific Oceans. Data acquisition by 3-D CAT scanning of intact coral cores is relatively rapid and inexpensive, enabling generation of many records of varying lengths from multiple colonies at each site, and, using techniques applied in dendrochronology, provide enough data to provide realistic error estimates on reconstructed SSTs. Funding will support 3 PIs, a post-doctoral research scientist, a PhD student, and research experience for an undergraduate.

过去 1000 年全球气温的代理重建为了解近期变暖趋势提供了背景，并可以更好地估计人为（温室气体）强迫对全球气候变化的贡献，主要从高纬度树木年轮记录中收集的数据表明，最近的变暖趋势。 20 世纪是上个千年中最温暖的时期，然而，与这些估计相关的不确定性很大，特别是在大约 700 年前结束的中世纪变暖时期。地球表面与全球热带地区最为接近，其中 75% 是海洋；但很少有来自低纬度海洋的跨越过去 1000 年的数据集，以改善全球温度重建并减少不确定性。迫切需要低纬度海洋的海面温度（SST）记录，这些珊瑚具有像树上的年轮一样在年带中积累碳酸钙骨架的潜力。 PI 最近应用了一种重建年度海表温度的方法，该方法利用了珊瑚骨骼生长与水温之间已证实的关系，在 3 个珊瑚物种生成的多个记录中，珊瑚生长占了 50-60% 的比例。仪器记录中的海表温度变化，在年际和更长的时间尺度上，将该方法应用于从巴哈马收集的长达约 440 年的缓慢生长的珊瑚，表明海表温度在现代的误差范围内。 AD1550，小冰河时期的海表温度比今天低约 1°C，并且过去 50 年的海表温度存在强烈的人为信号。PI 将在此基础上开展工作，重点是完善从珊瑚生长中提取海表温度的方法。记录并应用它来生成低纬度大西洋和太平洋的多个世纪的代理海表温度记录 通过完整珊瑚核心的 3D CAT 扫描进行数据采集相对快速且廉价，从而能够实现。从每个地点的多个菌落生成许多不同长度的记录，并使用树木年代学中应用的技术，提供足够的数据来对重建的海表温度进行现实的误差估计。资金将支持 3 名 PI，一名博士后研究科学家，一名博士生。 ，以及本科生的研究经验。