Collaborative Research: P2C2--Inferring Spatio-Temporal Variations in the Risk of Extreme Precipitation in the Western United States from Tree Ring Chronologies

该项目旨在了解极端冷季降水动态沿着美国西海岸通过分析的水分异常记录的树木年轮年表在整个海岸和内部的美国西部冬季高总降水量在沿海地区的特点是少数极端风暴，表现出不同的空间模式的降水在整个海岸和进一步的内陆。 基于这一观察，本研究将寻求开发一种新的树木气候证据应用，以探讨以下问题：a）极端降水变化如何在树轮年表网络中表达; B）这一信息能否提供有关导致这些极端事件的风暴路径时空变化的见解;以及c）如何对极端降水和风暴路径的联合变率进行建模，多的更广泛的影响包括更好地了解极端降水事件的潜力，这些事件造成了重大的社会成本造成人员伤亡和财产损失。 社会使用风险缓解策略来管理这种负担（例如，根据相对较短的仪器记录估计的历史极端降水变率，并可能在人为气候变化下发生变化。该项目将有助于确定这些影响的频率、持续性、重现性和地理格局在过去自然气候变化的情况下如何变化。这将为了解这些变化的原因以及未来可预测性的潜力提供重要的见解。 该项目还为研究生和博士后研究人员提供支持。县防洪区，美国陆军工程兵团，以及管理该地区极端事件风险的相关机构。这种直接参与将加强研究产品的应用，并为其设计提供指导。研究成果的创新可视化将通过哥伦比亚水中心提供给公众使用。

This project aims to understand extreme cold-season precipitation dynamics along the west coast of the United States through an analysis of the moisture anomalies recorded by tree-ring chronologies across the coast and interior of the western U.S. Winters with high total precipitation amounts in the coastal regions are marked by a small number of extreme storms that exhibit distinct spatial patterns of precipitation across the coast and further inland. Building from this observation, this research will seek to develop a novel application of dendroclimatic evidence to explore the following questions: a) how is extreme precipitation variability expressed in a network of tree-ring chronologies; b) can this information provide insight on the space-time variability of storm tracks that cause these extreme events; and c) how can the joint variability of extreme precipitation and storm tracks be modeled to develop consistent, multi-centennial reconstructions of both.The broader impacts include the potential to better understand extreme precipitation events which exert significant social costs through both loss of life and substantial damage to property. Society manages this burden using risk mitigation strategies (e.g., infrastructure, insurance) designed for historic extreme precipitation variability that is estimated from relatively short instrumental records and may be changing under anthropogenic climate change. This project will help determine how the frequency, persistence, recurrence and geographic pattern of these impacts have varied in the past under natural climate variability. This will provide important insights into the causes of these shifts and the potential for predictability in the future. This project also provides support for graduate and post-doctoral researchers.Outreach efforts will focus on high-level discussions with the L.A. County Flood Control District, U.S. Army Corps of Engineers, and related agencies that manage extreme event risk in the region. This direct engagement will enhance the application of the research products, as well as provide guidance for their design. Innovative visualizations of research output will be made available through the Columbia Water Center for public use.