Collaborative Research: Quantifying past water table depth and hydroclimate with dissolved noble gas isotopes in groundwater

合作研究：利用地下水中溶解的惰性气体同位素量化过去的地下水位深度和水文气候

基本信息

批准号：
1702571
负责人：
Martin Stute
金额：
$ 8.51万
依托单位：
Columbia University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2017
资助国家：
美国
起止时间：
2017-07-01 至 2022-06-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1702571&HistoricalAwards=false
关键词：
Collaborative Research Quantifying past water

项目摘要

Water resources are a critical issue for agriculture in the arid parts of the US, and it is likely that water availability will be affected by future climate change, yet it remains difficult to predict the magnitude of future rainfall changes. The proposed research will develop a new and precise method for quantifying past changes in water table depth, using measurements of dissolved noble gas isotopes in ancient groundwater. This knowledge of past water table fluctuations will help illuminate the regional rainfall response to climate variations, and strengthen predictions by providing rigorous tests of rainfall models. The method is based on the demonstrated fact that heavy gases settle to the bottom of the stagnant column of air in the soil above the water table depth. The deeper the water table, the more extreme the enrichment of heavy isotopes, and these heavy isotopes become dissolved in the water thus preserving information about the water table depth in aquifers containing ancient groundwater. This groundwater is already routinely sampled to learn about past temperature from the abundance of the noble gases; the proposed research will add water table depth to the information that can be extracted from the samples.

水资源是美国干旱地区农业的关键问题，可能会受到未来气候变化的影响，但很难预测未来降雨量的变化的幅度。拟议的研究将开发一种新的，精确的方法，用于使用古代地下水中溶解的贵气体同位素的测量来量化过去的地下水位深度变化。对过去地下水位波动的这种知识将有助于阐明区域降雨对气候变化的反应，并通过提供严格的降雨模型测试来增强预测。该方法基于以下事实，即沉积在地下水位深度上方土壤中停滞的空气柱的底部。地下水位越深，重量同位素的富集就越极端，这些沉重的同位素溶解在水中，从而保留了含有古代地下水的含水层中的地下水位深度的信息。这种地下水已经经常采样，以从贵族气体的丰度中了解过去的温度。拟议的研究将为可以从样品中提取的信息增加地下水位深度。

项目成果

期刊论文数量（1）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Widespread six degrees Celsius cooling on land during the Last Glacial Maximum

末次盛冰期陆地上普遍降温六摄氏度

DOI：
10.1038/s41586-021-03467-6
发表时间：
2021
期刊：
Nature
影响因子：
64.8
作者：
Seltzer, Alan M.;Ng, Jessica;Aeschbach, Werner;Kipfer, Rolf;Kulongoski, Justin T.;Severinghaus, Jeffrey P.;Stute, Martin
通讯作者：
Stute, Martin