This doctoral dissertation project investigates the climate and topographic controls on glacial advances during a period known as the Little Ice Age (LIA, approximately AD 1300 to 1850). Glaciers provide a critical freshwater supply in arid and semi-arid areas around the world, so understanding the dynamics of glaciers is of societal importance. Glacial advances and retreats are strongly affected by climate change, but are also influenced by local topographic and glaciological factors. These factors then can either reinforce or dampen the effects of changes in temperature and moisture. This project will constrain the formation ages of the landforms left behind by the LIA glacial advances to test whether the LIA glacial advances are asynchronous across a mountain region. Then, detailed mapping of the LIA and modern glacier extents from Google Earth imagery will be used to evaluate the relationship between the magnitude of the LIA glacial advances and local topographic and glaciological factors. Understanding the spatial and temporal pattern of the LIA glacial advances will provide significant insights into the shifting dominance of different atmospheric systems and their interplay with local topographic and glaciological factors. This knowledge is of critical importance for climate models to predict future climate scenarios. In particular, the detailed study from the sites selected in the Central Asian highlands will provide an understanding of relationships between the westerlies and the Siberian High, and possibly the Asian monsoon, in driving glacial advances and retreats over complex mountainous landscapes.
This project will fill a gap in knowledge of the timing and extent of the LIA glacial advances and provide well-constrained, paleo-climate information to help better understand future climate and environmental changes. The glacial maps delineated based on high-resolution Google Earth imagery will provide an updated glacier inventory to document the status of glacier changes. In addition to the support for this doctoral dissertation research, this project will provide training for an undergraduate student in geologic dating and paleo-climate reconstruction. Research results of this project will be disseminated to a variety of audiences through conference presentations, journal publications, and scientific outreach by integrating the research content into foreign language (Chinese) classes in local K-12 schools and the Confucius Institute at the University of Tennessee. As a Doctoral Dissertation Research Improvement award, this project will provide support to enable a promising student to establish an independent research career.