P2C2: Pan-American Precipitation Extremes and Multi-Decadal Regimes Reconstructed with Tree Ring Chronologies from the Amazon

该项目的目的是开发新的树木年轮年表在亚马逊重建降水，在整个美洲的热带和热带外降水极端的一致性文件，并检查亚马逊降水的观测，重建和模型模拟的几十年变化。 这项研究背后的基本原理是，气候模型对亚马逊流域水文气候变化的模拟表明，人为强迫可能会放大水文循环，导致更严重的干旱、极端洪水和大部分流域年降水量的下降。 然而，1950年之前的仪器观测有限，可能无法代表亚马逊地区年际至数十年降雨变化的全部范围。 在亚马逊地区，高分辨率的气候代用指标是罕见的，但树木年轮年表已被广泛用于重建中纬度北美和南美过去的特大干旱和多雨。 这些树木气候重建已被证明是有价值的测试模型模拟的气候动力学负责十年的湿度regimesThe潜在的更广泛的影响，包括进一步了解亚马逊河流域水文气候更广泛的科学界和公众。该项目产生的数据将远远超出研究的具体目标。与南美研究人员的能力建设是该项目的一个重要方面，网站开发和视频制作也是如此。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This project aims to develop new tree-ring chronologies in the Amazon to reconstruct precipitation, document coherence in tropical and extratropical precipitation extremes across the Americas, and examine multi-decadal variability of Amazon rainfall in observations, reconstructions, and model simulations. The rationale behind the research is that climate model simulations of hydroclimatic variability in the Amazon indicate that anthropogenic forcing may amplify the hydrologic cycle, resulting in more severe drought, extreme floods, and a decline in annual precipitation over most of the watershed. However, instrumental observations are limited before 1950 and may not represent the full range of inter-annual to multi-decadal rainfall variability over the Amazon. High-resolution climate proxies are rare in the Amazon, but tree-ring chronologies have been widely used to reconstruct past megadroughts and pluvials in mid-latitude North and South America. These dendroclimatic reconstructions have proven valuable for testing model simulations of the climate dynamics responsible for decadal moisture regimesThe potential Broader Impacts include furthering the understanding of Amazonian hydroclimate to the broader scientific community and public. The data generated by this project will be used far beyond the specific aims of the research. The capacity building with South American researchers is a strong aspect of the project as is website development and video production.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.