Collaborative Research: Dunefield Records of Late Quaternary Climatic Change, Northern China

该项目的目标是开发晚第四纪气候变化的新记录。它专门用于综合记录从最后一次冰盛期到现在的沙丘活动和相关的水文变化和尘埃产生，以及显示东亚季风环流过去的变化。这些结果将来自中国北部分布的沙丘区保存下来的地层和地貌证据。这项工作将由北美的科学家和中国合作进行，并将通过研究生和本科生参与实验室和实地工作来促进培训和学习。这项研究旨在解决的问题是：a)季风系统在轨道和千年时间尺度上的相对变化幅度；b)轨道时间尺度上变化的时间性和突发性以及通过模式实验再现它们的程度；以及c)中国北部以及半球和全球尺度上千年尺度气候变化的同步性。尽管任何给定研究地点的记录都可能是不完整的，并可能有多种解释，但来自许多不同地貌环境的综合记录有望提供相对直接的、可能是定量的古气候信息。这一景观尺度的记录也将对评估季风系统中陆地表面反馈的重要性很有价值。

The objective of this project is to develop new records of late Quaternary climatic change. It is designed specifically to yield a composite record of dune activity and associated hydrologic change and dust production from the Last Glacial Maximum to the present, as well as indicating past changes in the East Asian monsoon circulation. These results will derive from stratigraphic and geomorphic evidence preserved in dune fields distributed across northern China. The work will be undertaken collaboratively by scientists in North America and China, and will promote training and learning through the involvement of graduate and undergraduate students in both laboratory and field work. Questions this research is designed to resolve are: a) the relative magnitude of change in the monsoon system at orbital and millennial timescales; b) the timing and abruptness of change at the orbital timescale and the degree to which they are reproduced by model experiments, and c) the synchroneity of millennial-scale climatic change across northern China, as well as on hemispheric and global scales. While the record at any given study site may be incomplete and open to multiple interpretations, a composite record from many different geomorphic settings is expected to provide relatively straightforward, potentially quantitative paleoclimatic information. This landscape-scale record will also be valuable in assessing the importance of land-surface feedbacks in the monsoon system.