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.

人为二氧化碳排放正在改变地球的气候。然而，气候在数十年的时间尺度上也自然变化。表征这种变异性对于量化人为影响和预测未来变化至关重要。海面温度（SST）在气候中起着重要作用，但工具记录太短了，无法对自然变异性进行强有力的评估。珊瑚骨骼产生的代理数据有可能填补这些空白，但是产生的冗长记录需要使用在乐器时代之前生长的死殖民地，而现有的地球化学SST代理不适合使用。已经开发了一种新的温度计SR-U，以应用于非生存的珊瑚，但SST的校准需要测试。该项目试图通过重建中央红海的记录并与该地区受良好约束的观察性SST进行比较来验证SR-U。成功的结果将通过为SST重建的全球非生存珊瑚开放全球档案，从而使科学界受益。改进的SST重建将为用于预测未来海洋学和气候变化的相同数值模型提供一个目标。轨道到轨道的地球化学可变性是来自非生存珊瑚和SR-U的SST重建的主要障碍，而SR-U是基于对导致这种变异性的过程的强有力理解。该项目将在过去50年中从中央红海中采样的现有Porites珊瑚核心生成SR/CA和U/CA数据，并应用源自大西洋物种的校准来重建SST记录。该地区的重型船舶交通意味着卫星前观察记录受到良好的约束。此外，在过去50年中，红海SST的特征是衰老的变异性叠加在长期变暖趋势上，因此对SR-U捕获未知珊瑚中变异性和趋势的能力进行了理想的测试。目标是概念验证，以证明SR-U作为一种使用现代和化石珊瑚重建准确的SST记录的工具的普遍应用。