(ESH) Glacial Paleotemperatures for the Continental Tropics Derived from Noble Gases Dissolved in Groundwater

(ESH) 源自地下水中溶解的稀有气体的大陆热带冰川古温度

• 批准号: 9506425
• 负责人: Martin Stute
• 金额: $ 25万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-08-15 至 1998-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9506425&HistoricalAwards=false
• 关键词: ESH; Glacial; Paleotemperatures; Continental; Tropics

9506425 Stute One of key questions in paleoclimate research is the degree of change in tropical surface temperatures between today and the last glacial maximum (LGM). Most sea surface temperature records suggest small (1oC) glacial/interglacial temperature changes, while continental records indicate considerably larger temperature changes. A resolution of this conflict is crucial for a reliable reconstruction of past and prediction of future climate change. We plan to address this issue by improving the continental climate record in the tropics at low altitude, which at this stage is less quantitative than the sea surface temperature record. We will use the concentrations of atmospheric noble gases dissolved in groundwater as paleothermometer ('noble gas thermometer') and confined aquifer as archive of climate change. We request funds for collection and evaluation of geochemical data (He, Ne, Ar, Kr, Xe, 14 C, 13 C, D , 18 O 34 S and major dissolved ions) from two groundwater flow systems in the tropics, the Mekong Delta aquifers in southern Vietnam and the Rio Guayas aquifers in Ecuador. Noble gas paleotemperature records from these aquifers will allow quantitative reconstruction of paleotemperature records for the continental tropics covering the past 30,000 years. The aquifers are located at altitudes less than 100 aaaaam a.s.l. and close to the eastern and western coasts of the Pacific. The records obtained from these aquifers will therefore allow us to directly compare continental and oceanic paleotemperatures during the last glaciation.

[506425] Stute古气候研究的关键问题之一是热带地表温度从今天到末次极盛期（LGM）的变化程度。大多数海面温度记录显示小的（1℃）冰期/间冰期温度变化，而大陆记录显示较大的温度变化。解决这一冲突对于可靠地重建过去和预测未来气候变化至关重要。我们计划通过改善热带低空大陆性气候记录来解决这个问题，在这个阶段，这比海洋表面温度记录要少得多。我们将使用地下水中溶解的大气稀有气体浓度作为古温度计（“稀有气体温度计”），并使用承压含水层作为气候变化的档案。我们申请资金用于收集和评估两个热带地下水流动系统的地球化学数据（He, Ne, Ar, Kr, Xe, 14 C, 13 C， D， 18 O 34 S和主要溶解离子），分别来自越南南部的湄公河三角洲含水层和厄瓜多尔的里约热内卢瓜亚斯含水层。来自这些含水层的惰性气体古温度记录将允许定量重建大陆热带地区过去3万年的古温度记录。这些含水层位于海拔低于100英尺的地方，靠近太平洋的东西海岸。因此，从这些含水层获得的记录将使我们能够直接比较末次冰期期间大陆和海洋的古温度。