Collaborative Research: A Southern Hemispheric Perspective on Holocene Climate Variability Based on Mountain Glacial Chronologies

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。该小组将测试有关全新世期间南半球气候与北方半球气候相比的时空变化的假设。这项研究将通过提供南半球气候变化的视角来帮助解决古气候的驱动因素。利用最近的分析进展，该小组使用10 Be测量直接确定全新世中晚期冰碛的年代。这些年龄提供了一个新的视角，特别是当与其他代理记录相结合时，对南方陆地大气气候变率。重点是在南部的安第斯山脉，那里的冰冻圈是特别敏感的大气温度和降水的变化的陆地冰覆盖的历史。这一新的年表说明了在巴塔哥尼亚和南半球的陆地冰的变化，在中晚全新世和20/21世纪的变化的背景。巴塔哥尼亚位于地球仪的一个关键区域，可以深入了解过去大气气候变化的变化。它是位于~46°S和南极洲之间的唯一一个同时受极地和中纬度气候影响的大陆，现代人类文明是在全新世气候变化的背景下发展起来的，古气候学的重要目标之一就是了解这种变化的原因。正如IPCC所指出的，由于缺乏过时的古气候记录，对南半球气候的了解，特别是在过去的2000年里，受到“严重限制”。这项研究通过使用一种新的方法来确定晚全新世冰碛的年代，有助于改变我们对南半球古气候的理解。这种技术可以研究由于缺乏有机物质而难以确定日期的序列。该项目还提高了我们对20/21世纪冰川变化的理解，这些变化在两个半球之间可能是不同的。该项目协调冰川地质学和地质年代学方面的专业知识，以及冰川气候建模和古生态学专家之间的合作。更广泛的影响包括加强美国大学之间的关系，英国、智利、阿根廷和新西兰。国际合作涉及几位相对接近职业生涯开始的科学家。PI都积极参与教育和宣传，其中涉及世界上最繁忙的国家公园之一的冰川历史。结果将在开放的数据集中提供，并在公园中展出。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).The group will test hypotheses concerning how temporal and spatial variability of Southern Hemisphere climate compared with the Northern Hemisphere during the Holocene. This research will help resolve drivers of paleoclimate by providing a perspective on Southern Hemisphere climate changes. Using recent analytic advances, the group uses 10Be measurements to directly date mid- to late Holocene moraines. These ages provide a new perspective, especially when combined with other proxy records, on Southern terrestrial-atmosphere climate variability. The focus is on the history of land ice-cover in the southern Andes, where the cryosphere is particularly sensitive to changes in atmospheric temperature and precipitation.This new chronology illustrates changes in land ice in Patagonia and the Southern Hemisphere during the mid- to late Holocene and the context for 20th/21st century changes. Patagonia is in a key area of the globe to provide insight into past changes in atmospheric climate variability. It is the only major landmass between ~46°S and Antarctica in an area affected by both polar and middle latitude climate regimes.Modern human civilization has developed against the backdrop of Holocene climate variability, and one of the most important goals in paleoclimatology has been to understand the causes of this variability. As pointed out by the IPCC, knowledge of Southern Hemisphere climate, especially over the last 2000 years, is 'severely limited' by the lack of dated paleoclimate records. The proposed research helps transform our understanding of Southern Hemisphere paleoclimate by using a new approach to date Late Holocene moraines. This technique allows study of sequences that have been difficult to date because of a lack of organic matter. This project also improves our understanding of 20th/21st century changes in glaciers, which may be different between the hemispheres. The project coordinates expertise in glacial geology and geochronology and collaboration between experts in glacier-climate modeling and paleoecology. Broader impacts include strengthening the relations between universities in the U.S., UK, Chile, Argentina, and New Zealand. The international collaborations involve several scientists relatively close to the start of their careers. The PIs are all actively engaged in education and outreach, which involves the glacial history of one of the busiest national parks in the world. The results will be avilable in open datasets, and on displays in the parks.