Collaborative Research: P2C2--Reconstructing Southern Rocky Mountains Warm Season Temperature for the Past 2000 Years

研究的总体目标是利用里约热内卢Grande Headwaters地区的狐尾松进行2000年的温度重建，并增加更新和新的水文气候重建，以评估长期的区域温度和水文气候关系。异常温暖的夏季气温通过增加蒸散速率和降低土壤水分来减少径流，这种影响持续到冬季和随后的夏季。然而，对于最近的气候变暖在多大程度上影响了100亿立方米的上游水流，人们存在分歧。该项目将利用仪器数据集、更新的里约热内卢大流量重建和当地降水重建来分析径流效率（降水转化为径流的比例）随时间的变化，以评估干旱和雨淋期间温度在调节径流效率方面的作用。格兰德河为200多万英亩的农田和600多万人提供地表水。主要支持农业和农村经济，里约热内卢格兰德也服务于城市中心，包括阿尔伯克基，埃尔帕索和城Juárez。持续的干旱导致了严重的水资源短缺，然而，与科罗拉多河上游盆地相比，里约热内卢格兰德河的研究不足，可能是因为这条河所服务的社区比例较低。该项目将古气候信息应用于实践，通过与上游里约热内卢格兰德水利益相关者接触，了解他们对供水和管理的关注。潜在的更广泛的影响包括加深对美国西南部水资源的了解，支持博士后研究人员，以及与该地区水资源管理者和利益相关者的实质性互动。该奖项反映了美国国家科学基金会的法定使命，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。

The general goal of the research is to use bristlecone pine from the Rio Grande Headwaters region to develop a temperature reconstruction spanning 2,000 years, augmented with updated and new hydroclimate reconstructions, to evaluate long-term, regional temperature and hydroclimate relationships.Anomalously warm summer temperatures reduce runoff by increasing the rates of evapotranspiration and by decreasing soil moisture, which has a persistent effect into winter and the following summer. However, there is disagreement to the extent to which recent warming has influenced upper Rio Grande flows. This project will address changes in runoff efficiency (the proportion of precipitation that becomes runoff) over time using instrumental datasets, an updated Rio Grande streamflow reconstruction, and a local precipitation reconstruction to assess the role of temperature in modulating runoff efficiency during droughts and pluvials.The Rio Grande supplies surface water to over 2 million acres of agriculture and over 6 million people. Predominantly supporting agriculture and rural economies, the Rio Grande also serves urban centers including Albuquerque, El Paso, and Ciudad Juárez. Ongoing drought has led to severe water shortages, yet the Rio Grande has been understudied compared to the upper Colorado River basin, possibly due to the proportion of poorly-represented communities the river serves. This project moves toward placing paleoclimate information into practice by engaging with upper Rio Grande water stakeholders in order to understand their water supply and management concerns.The potential Broader Impacts include greater understanding of water resources in the southwestern United States, support for a post-doctoral researcher, and substantive interaction with water resource managers and stakeholders in the region.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.