Early-concept grant for exploratory research (EAGER) proposal: Accessing the potential of clumped isotope thermometry to constrain temperatures in the Arctic during the Pliocene

探索性研究早期概念资助 (EAGER) 提案：利用聚集同位素测温技术限制上新世北极温度的潜力

• 批准号: 1215551
• 负责人: Aradhna Tripati
• 金额: $ 23.59万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-04-01 至 2014-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1215551&HistoricalAwards=false
• 关键词: Early; concept; grant; exploratory; research

The specific goal of this research is to identify whether carbonate ?clumped isotope? thermometry can be applied to mollusks to accurately and precisely reconstruct temperatures in the Arctic. Previous work has shown that the occurrence of multiple rare isotope substitutions in carbonate minerals, also referred to as the ?clumping? of heavy isotopes into bonds with each other, is temperature dependent. This temperature proxy is also independent of the del-18O of water and the del-13C of dissolved inorganic carbon. Initial studies of biologically-precipitated calcite and aragonite by the PI and co-PI and collaborators indicate that the measurements of 13C-18O bond abundance should allow one to make a relatively assumption-free determination of the temperature at which a mineral formed. Although this new proxy looks promising, calibration of the clumped isotope thermometer at low temperatures (i.e., below 15°C) is limited. Therefore the utility of this proxy for climate reconstructions in the Arctic is unclear. This project will determine the accuracy and precision of the technique when applied to biological samples grown at Arctic temperatures and, consequently, the ability of this technique to assess paleo ocean temperatures in polar regions.The instrumental record of temperature only goes back in time a few hundred years, at most. In order to understand the natural variability of temperature, either locally or globally, we require much longer records. To develop such records, we rely on proxy measurements for temperature. Use of such proxies requires assumptions and often imposes large error bars on the estimated temperature. This project will determine the usefulness of a new proxy in the polar regions.

这项研究的具体目标是确定碳酸盐是否块化同位素？可以将温度计应用于软体动物，以准确，精确地重建北极的温度。先前的工作表明，在碳酸盐矿物质中发生多个稀有同位素取代，也称为块状？彼此的重型同位素彼此之间的键为键。该温度代理也与Del-18O的水和溶解的无机碳的DEL-13C无关。 PI和Co-Pi和合作者对生物学成分的钙和芳香族的初步研究表明，13C-18O键抽象的测量应允许人们对形成矿物质的温度进行相对的无假设确定。尽管这种新的代理看起来很有希望，但在低温下（即15°C以下），簇的同位素温度计的校准受到限制。因此，该代理在北极的气候重建效用尚不清楚。当应用于在北极温度下生长的生物样品时，该项目将确定该技术的准确性和精度，因此，该技术评估极性区域的古海洋温度的能力。温度的工具记录仅在几百年时才能回溯。为了了解本地或全球温度的自然变异性，我们需要更长的记录。为了制定这样的记录，我们依靠代理测量温度。使用此类代理需要假设，并且在估计温度上通常不可能发生较大的误差线。该项目将确定新代理在极地地区的有用性。