CAREER: Tree-Ring Based Reconstruction of Northern Hemisphere Jetstream Variability

职业：基于树木年轮的北半球急流变率重建

• 批准号: 1349942
• 负责人: Valerie Trouet
• 金额: $ 58.74万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-15 至 2020-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1349942&HistoricalAwards=false
• 关键词: CAREER; Tree; Ring; Based; Reconstruction

The Northern Hemisphere Jet, a high altitude narrow path of strong winds that meanders around the globe, is a key factor in the strength and perseverance of mid-latitude extreme weather events. Some studies have suggested that the jet may slow and change trajectory with ongoing and future climate change. Such behavior has been exemplified by the California drought, the eastern US polar vortex, and the winter storms in England in the winter of 2013-2014. Arctic amplification (the stronger warming of high Northern Hemisphere latitudes compared to lower latitudes) may drive jet stream variability in recent decades, but the role of man-made climate change in jet stream variability is contested and the instrumental period of measurement is too short to draw firm conclusions about current and future jet stream trends.This research will reconstruct the latitudinal position of the jet over the last 500+ years using tree-ring records. The project will generate a new tree-ring based summer temperature reconstruction for the Balkans and combine it with proxy data from northwestern Europe to reconstruct the summer North Atlantic Jet. For the winter North Pacific Jet, the work will combine new winter climate-sensitive series from the northern Rockies with chronologies from central California. These two 500+ year-long regional jet stream reconstructions will be used to put current jet stream trends in a historical perspective.The centerpiece of the education component of this CAREER award is the development of a new Global Change Analysis course that would offer training in quantitative methods to students across the broad, interdisciplinary global change research community at the University of Arizona. The project also includes a multi-faceted outreach approach that capitalizes on the contingency of women in climate change science at the University of Arizona and is designed to excite future generations about science careers. Finally, the project includes international partnerships and field expeditions with researchers from Bulgaria, Slovenia, and Switzerland, including technology knowledge transfer (in x-ray densitometry) that will enable new capabilities in the US.This project is jointly supported by the Paleoclimate Program and NSF's office of International Science and Engineering.

北半球急流是在全球范围内盘旋的高空狭窄强风路径，是中纬度极端天气事件强度和持久性的关键因素。一些研究表明，随着正在进行的和未来的气候变化，喷气式飞机可能会减速并改变轨迹。加州干旱、美国东部极地涡旋和英国2013-2014年冬季的冬季风暴就是这种行为的例证。北极放大(北半球高纬度比低纬度变暖)可能会在近几十年推动急流变化，但人为气候变化在急流变化中的作用存在争议，仪器测量周期太短，无法对当前和未来的急流趋势得出确定的结论。这项研究将利用树轮记录重建过去500多年来急流的纬度位置。该项目将为巴尔干地区生成一个新的基于树轮的夏季温度重建，并将其与来自欧洲西北部的代理数据相结合，以重建夏季北大西洋急流。对于冬季北太平洋喷气式飞机，这项工作将结合来自落基山脉北部的新的冬季气候敏感系列和来自加利福尼亚州中部的年表。这两个长达500多年的区域急流重建将被用来将当前的急流趋势放在历史的角度来看待。这个职业奖项的教育部分的核心是开发一门新的全球变化分析课程，该课程将为亚利桑那大学广泛的、跨学科的全球变化研究社区的学生提供量化方法方面的培训。该项目还包括一种多方面的外展方法，利用亚利桑那大学气候变化科学领域女性的偶然性，旨在激发子孙后代对科学事业的兴趣。最后，该项目包括与保加利亚、斯洛文尼亚和瑞士的研究人员的国际伙伴关系和实地考察，包括技术知识转移(在X射线密度测量方面)，将使美国具有新的能力。该项目由古气候计划和美国国家科学基金会国际科学与工程办公室联合支持。