Validation of the Strontium-Uranium Thermometer Against Instrumental Records of Ocean Temperature

根据海洋温度仪器记录验证锶-铀温度计

• 批准号: 1747746
• 负责人: Anne Cohen
• 金额: $ 3.32万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2018-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1747746&HistoricalAwards=false
• 关键词: Validation; Strontium; Uranium; Thermometer; Against

Anthropogenic CO2 emissions are changing Earth's climate. Yet climate also varies naturally on timescales of decades to millennia. Characterizing this variability is critical to both quantifying the anthropogenic influence and projecting future change. Sea surface temperature (SST) plays a major role in climate yet the instrumental record is too short to enable a robust evaluation of natural variability. Proxy data generated from coral skeletons have potential to fill these gaps but generation of lengthy records requires use of dead colonies that grew before the instrumental era, for which existing geochemical SST proxies are not well-suited. A new thermometer, Sr-U, has been developed for application to non-living corals but the calibration to SST requires testing. This project seeks to validate Sr-U by reconstructing a record for the central Red Sea and comparing against well-constrained observational SSTs for the region. A successful outcome will benefit the scientific community by opening the global archive of non-living corals for SST reconstructions. Improved SST reconstructions will provide a target for the same numerical models used to predict future oceanographic and climate change.Coral-to-coral geochemical variability is a major obstacle to SST reconstructions from non-living corals and Sr-U is based on a robust understanding of the processes that cause this variability. This project will generate Sr/Ca and U/Ca data for the last 50 years from an existing Porites coral core sampled in the central Red Sea and apply a calibration derived from Atlantic species to reconstruct the SST record. Heavy ship traffic in the region means the pre-satellite observational record is well-constrained. Additionally, Red Sea SSTs over the last 50 years are characterized by decadal variability superimposed on a long-term warming trend, and thus present an ideal test of the ability of Sr-U to capture both variability and trends in an unknown coral. The goal is a proof-of-concept, to demonstrate the universal application of Sr-U as a tool with which to reconstruct accurate SST records using modern and fossil corals alike.

人为的二氧化碳排放正在改变地球的气候。然而，气候也在几十年到几千年的时间尺度上自然变化。描述这种变异性对于量化人为影响和预测未来变化都至关重要。海表温度（SST）在气候中起着重要作用，但仪器记录太短，无法对自然变率进行可靠的评估。从珊瑚骨骼生成的代理数据有可能填补这些空白，但生成冗长的记录需要使用死亡的殖民地，仪器时代之前，现有的地球化学SST代理不太适合。一种新的温度计Sr-U已经研制出来，用于测量非活珊瑚，但对SST的校准需要进行测试。该项目旨在通过重建红海中部的记录并与该地区受约束的观测SST进行比较来验证Sr-U。成功的结果将有利于科学界开放全球非生命珊瑚档案，用于SST重建。改进SST重建将提供一个目标，用于预测未来的海洋和气候变化的相同的数值模型。珊瑚珊瑚的地球化学变异是一个主要的障碍，SST重建从非活珊瑚和锶铀是基于一个强大的理解的过程，导致这种变化。该项目将产生Sr/Ca和U/Ca的数据，在过去50年中，从现有的滨珊瑚珊瑚芯采样在红海中部，并应用来自大西洋物种的校准重建SST记录。该地区繁忙的船舶交通意味着卫星前的观测记录受到很好的限制。此外，红海SST在过去50年的特点是叠加在长期变暖趋势上的十年变化，因此提出了一个理想的测试锶铀捕获未知珊瑚的变化和趋势的能力。目标是概念验证，以证明Sr-U作为一种工具的普遍应用，使用现代和化石珊瑚重建准确的SST记录。