Collaborative Research: Reconstructing Droughts in the Tropical Americas Using Tree-Ring Analysis

合作研究：利用树木年轮分析重建热带美洲的干旱

• 批准号: 1619798
• 负责人: Kevin Anchukaitis
• 金额: $ 4.45万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-10-20 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1619798&HistoricalAwards=false
• 关键词: Collaborative; Research; Reconstructing; Droughts; Tropical

This project uses the annual rings of tropical trees to reconstruct past rainfall in a drought- and famine-prone region, then applies this knowledge to understanding the role of natural and human-altered variability in the climate system in influencing regional patterns of drought in the past, present, and future. Prior research determined that high elevation tree species in Guatemala and Honduras do form annual growth rings that can be dated to their exact year of formation; this is unusual for tropical tree species. It is understood that variations in ring width in these trees reflect the amount of winter and spring rainfall. With this knowledge, the investigators will develop estimates of past precipitation along Guatemala's 'Dry Corridor,' a region that currently suffers from severe water and food security challenges. Tree-ring data will be collected from mountain sites across this region, and these will be used to develop estimates of past rainfall over the last five centuries or more. The benefit of these precipitation reconstructions using tree rings is that they can be used to understand whether current climate variability is exceptional compared to the last several centuries and the extent to which natural variability is entwined with a human-influenced changes. Specifically this research will evaluate the hypothesis that there are important modes of natural variability in Central American rainfall at time scales of decades and longer. This knowledge will help test and improve models that predict future rainfall trends both regionally and globally and can be applied to understanding their cause and consequences.This research expands the geographic extent of annual, climate-sensitive tree-ring data further into the American tropics. Knowledge gained from this project will be relevant in a region with populations that are particularly vulnerable to climate change, as it is likely that increases in drought and flooding will be the most direct and immediate consequences of global warming for human society. Changes in rainfall exacerbate existing and emerging threats to sustainable water supplies from growing populations, pollution, declining infrastructure, and boundary conflicts. A long-term perspective on the potential range of variability in precipitation, and in particularly decadal-scale fluctuations, is critical for predicting and planning for the consequences of changes in water availability. This research project provides a hands-on and international research experience for both graduate and undergraduate students from the United States and also facilitates the involvement of Central American students and scientists in geographic research with US collaborators. Coordination between US and Central American scientists will facilitate skills training and knowledge development so that local resources and information are available to address sustainability and vulnerability reduction efforts. This award is being co-funded by NSF's Office of International and Integrative Activities.

该项目使用热带树的年度环在干旱和容易饥荒的地区重建过去的降雨，然后将此知识应用于理解自然和人类改变的变异性在气候系统中的作用，在影响干旱地区的区域模式中，过去，现在和未来。 先前的研究确定，危地马拉和洪都拉斯的高海拔树种确实会形成年度生长环，可以追溯到其确切的形成年度。对于热带树种来说，这是不寻常的。 据了解，这些树木的环宽变化反映了冬季和春季降雨的数量。 有了这些知识，调查人员将估计危地马拉沿危地马拉的“干走廊”的降水，该地区目前面临严重的水和粮食安全挑战。树环数据将从该地区的山区收集，这些数据将用于开发过去五个世纪以上过去降雨的估计值。 使用树环重建的这些降水重建的好处是，它们可用于了解与过去几个世纪相比，当前的气候变异性是否异常，以及自然可变性与人类影响的变化纠缠在一起的程度。 具体而言，这项研究将评估以下假设：中美洲降雨在数十年和更长的时间尺度上存在重要的自然变异模式。这些知识将有助于测试和改进模型，以预测区域和全球范围内的未来降雨趋势，并可以应用于理解其原因和后果。这项研究将年度，气候敏感的树环数据的地理范围进一步扩展到美国热带地区。 从该项目中获得的知识将与一个特别容易受到气候变化的人群有关，因为干旱和洪水的增加可能是全球变暖对人类社会的最直接和直接后果。 降雨的变化加剧了现有的现有和新兴的威胁对人口不断增长，污染，基础设施下降和边界冲突的可持续水供应。 对降水的潜在可变性范围的长期视角，尤其是衰老规模的波动，对于预测和计划水的后果至关重要。 该研究项目为来自美国的研究生和本科生提供了动手和国际研究经验，并促进了中美洲学生和科学家与美国合作者参与地理研究。我们与中美洲科学家之间的协调将促进技能培训和知识发展，以便可以解决当地资源和信息，以解决可持续性和脆弱性的工作。 该奖项由NSF国际和综合活动办公室共同资助。