ESH - Completion of a North-South Transect of Glacial Paleotemperatures Along the Americas Derived from Noble Gases Dissolved in Groundwater

9706467 Stute古气候研究的关键问题之一是两个半球的对称程度和气候变化机制。我们计划通过改善南美洲最后一个冰期的大陆气候记录来解决这个问题。我们将主要利用14C年代地下水中溶解的大气稀有气体的浓度，这些地下水被用作气候变化的档案。我们申请资金用于收集和评价南美两个地下水流动系统（巴西的Botucatu含水层和阿根廷的Bahia Blanca含水层）的地球化学数据（He、Ne、Ar、Kr、Xe、14C、13C、D、18O、34S、3H和主要溶解离子）。这些含水层的惰性气体古温度记录将为南美洲过去35000年的古温度提供定量重建。这两项记录将根据地下水流动系统中记录的“惰性气体温度”，完成沿美洲的冰川古温度南北样带。样带将(1)使我们能够解决长期气候变化的半球间对称性，(2)为目前使用的古气候代用物提供更坚实的基础，(3)帮助我们更好地理解南北半球之间的气候变化耦合。这项工作通过PEP I （PAGES的子程序）直接有助于实现IGBP的目标。此外，我们还要求资助在我们以前的古气候研究框架中记录的稀有气体测温的一些新方法方面的研究。

9706467 Stute One of the key questions in paleoclimate research is the degree of symmetry and the mechanisms of climate change on both hemispheres. We plan to address this issue by improving the continental climate record for the last glacial period in South America. We will primarily use the concentrations of atmospheric noble gases dissolved in 14C dated groundwater which is used as archive of climate change. We request funds for collection and evaluation of geochemical data (He, Ne, Ar, Kr, Xe, 14C, 13C, D, 18O, 34S, 3H and major dissolved ions) from two groundwater flow systems in South America, the Botucatu aquifer in Brazil, and the Bahia Blanca aquifer in Argentina. Noble gas paleotemperature records from these aquifers will provide quantitative reconstruction of paleotemperatures for South America covering the past 35,000 years. These two records will complete a glacial paleotemperature north-south transect along the Americas based on 'noble gas temperatures' archived in groundwater flow systems. The transect will (1) allow us to address the interhemipheric symmetry of long-term climate change, (2) provide a firmer footing for presently used paleoclimatic proxies, and (3) help us to better understand the coupling of climate change between the northern and southern hemispheres. This work contributes directly to the goals of IGBP through PEP I, a subprogram of PAGES. Additionally, we request funds for studies of some new methodological aspects of noble gas thermometry which were documented in the framework of our previous paleoclimate studies.