Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment

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项目编号	1443346
	Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment
	John Stone
主持机构	University of Washington
项目开始年	2016
	2016-08-01
项目结束日期	2019-07-31
资助机构	US-NSF
项目类别	Standard Grant
项目经费	254977(USD)
国家	美国
语种	英语
英文摘要	The response of the Antarctic Ice Sheet to future climatic changes is recognized as the greatest uncertainty in projections of future sea level. An understanding of past ice fluctuations affords insight into ice-sheet response to climate and sea-level change and thus is critical for improving sea-level predictions. This project will examine deglaciation of the southern Ross Sea over the past few thousand years to document oscillations in Antarctic ice volume during a period of relatively stable climate and sea level. We will help quantify changes in ice volume, improve understanding of the ice dynamics responsible, and examine the implications for future sea-level change. The project will train future scientists through participation of graduate students, as well as undergraduates who will develop research projects in our laboratories. Previous research indicates rapid Ross Sea deglaciation as far south as Beardmore Glacier early in the Holocene epoch (which began approximately 11,700 years before present), followed by more gradual recession. However, deglaciation in the later half of the Holocene remains poorly constrained, with no chronological control on grounding-line migration between Beardmore and Scott Glaciers. Thus, we do not know if mid-Holocene recession drove the grounding line rapidly back to its present position at Scott Glacier, or if the ice sheet withdrew gradually in the absence of significant climate forcing or eustatic sea level change. The latter possibility raises concerns for future stability of the Ross Sea grounding line. To address this question, we will map and date glacial deposits on coastal mountains that constrain the thinning history of Liv and Amundsen Glaciers. By extending our chronology down to the level of floating ice at the mouths of these glaciers, we will date their thinning history from glacial maximum to present, as well as migration of the Ross Sea grounding line southwards along the Transantarctic Mountains. High-resolution dating will come from Beryllium-10 surface-exposure ages of erratics collected along elevation transects, as well as Carbon-14 dates of algae within shorelines from former ice-dammed ponds. Sites have been chosen specifically to allow close comparison of these two dating methods, which will afford constraints on Antarctic Beryllium-10 production rates.
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文献类型	项目
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/69950
专题	环境与发展全球科技态势
推荐引用方式 GB/T 7714	John Stone.Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment.2016.