High-Resolution Record of Upper Mississippi River Flood Responses to Holocene Climate Change

密西西比河上游洪水对全新世气候变化响应的高分辨率记录

• 批准号: 0112614
• 负责人: James Knox
• 金额: $ 37.42万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-15 至 2005-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0112614&HistoricalAwards=false
• 关键词: Resolution; Record; Upper; Mississippi; River

The general objective of this research is to examine the history of alluvial sedimentation of the Upper Mississippi River (UMR) to advance our understanding of how climate variability influences the magnitudes and timing of floods on the main channel of the UMR in western Wisconsin. This mid continent site contains a nearly continuous alluvial record that extends nearly 10,000 years and provides a unique opportunity to examine the history of long- and short-term extreme flow events in this important watershed. The specific goals of this research are to: 1) obtain high-resolution records that can help reconstruct Holocene floods in the main and secondary channels of the Upper Mississippi River (UMR); 2) quantitatively link the flood regime of the main channel to independent paleoclimate proxies obtained from other researchers; 3) quantify and contrast the response of the UMR system to extreme hydrologic events during abrupt climate change and gradual climate change; 4) quantify the response of flood hydrology to the relative changes in climate change (i.e., warmer/wetter, warmer/drier, etc) inferred from proxies. These specific goals will be achieved by a combination of field, laboratory, statistical, and modeling analyses.The research is important because changes in the frequency or intensity of extreme river flows have the potential to produce major impacts on both human society and the natural environment. Instrumental records are too short to adequately determine how climate changes fully influence extremes in flow hydrology on large river systems such as the UMR. Results from this research will help us understanding how terrestrial hydrologic systems respond to changes in global scale atmosphere circulation. The results also should be useful for understanding the relationship between changing climate and recurring extreme hydrologic events.

这项研究的总体目标是考察密西西比河上游(UMR)的冲积沉积历史，以促进我们对气候变化如何影响威斯康星州西部UMR主河道洪水的规模和时间的理解。这个中大陆遗址包含了几乎连续的冲积记录，持续了近10,000年，为研究这一重要分水岭的长期和短期极端径流事件的历史提供了独特的机会。这项研究的具体目标是：1)获得能够帮助重建密西西比河上游主要和次要河道全新世洪水的高分辨率记录；2)将主要河道的洪水状况与从其他研究人员获得的独立古气候指标联系起来；3)量化和对比UMR系统对突然气候变化和逐渐气候变化期间极端水文事件的响应；4)量化洪水水文学对从指标推断的气候变化(如变暖/变湿、变暖/变干等)的相对变化的响应。这些具体目标将通过现场分析、实验室分析、统计分析和模型分析相结合来实现。研究之所以重要，是因为极端河流流动的频率或强度的变化可能对人类社会和自然环境产生重大影响。仪器记录太短，无法充分确定气候变化如何充分影响UMR等大型河流系统的径流水文学极端情况。这项研究的结果将有助于我们了解陆地水文系统如何响应全球尺度大气环流的变化。这些结果也将有助于理解气候变化和反复发生的极端水文事件之间的关系。