Collaborative Research: Understanding the Full Range of Amazon Drought and Impacts

合作研究：全面了解亚马逊干旱及其影响

• 批准号: 1303831
• 负责人: Mark Bush
• 金额: $ 35.19万
• 依托单位: Florida Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-02-01 至 2020-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1303831&HistoricalAwards=false
• 关键词: Collaborative; Research; Understanding; Full; Range

TECHNICAL DESCRIPTIONThis grant will provide improved paleoclimatic and paleo-drought perspectives needed to manage Amazonia in the face of natural climate variability and change. The project targets three clusters of western Amazonian lakes in Brazil, Ecuador and Peru to establish a regional network of at least four sub-decadally resolved 1500- to 3000-year long integrated records of paleoclimate, vegetation, and fire-history for western Amazonia. The team will use a climate and Earth system modeling strategy to address many questions, including:*To what extent are the hypothesized drought events in each lake record really droughts, i.e., reproduced in other lake records nearby (restricted drought) and over 1,000 km away (broader drought)?*What are the best "paleo-informed" estimates of drought and abrupt change risk for Amazonia?*How did Amazonian vegetation and fire dynamics respond to the spectrum of past drought severity, and how might these biophysical feedbacks affect future forest sustainability and the risk of a tipping point?*Is there early warning behavior in the Amazonian dynamical system approaching critical transitions?*How well do state-of-the-art models simulate the observed record of drought and abrupt change?*What are the dominant controls on decadal to century-scale drought variability and abrupt hydro climatic change in Amazonia?NON-TECHNICAL DESCRIPTIONIn 2005, the Amazon basin was hit with a drought unprecedented in the period of instrumental observation. Scientists quickly realized this drought was a new threat that put Amazonia's biodiversity, ability to act as a carbon sink, and ecosystem services (e.g., hydrologic and economic) at risk. In 2010, a second, more severe drought occurred. It has been posited that Amazonia might not survive accelerating climate change, perhaps even reaching a tipping point beyond which substantial areas of the forest would convert irreversibly to savanna.The University of Arizona and Florida Institute of Technology team has collected data showing that single-year periods of severe drought were not uncommon in Amazonia, and that longer multi-year (up to ~15 yr) droughts and abrupt climate changes have also occurred. Comparisons between this 1500-year record and state-of-the-art climate model simulations also indicated that models might underestimate the risk of future prolonged Amazonian drought. As carbon feedbacks are important components of modern fully-coupled climate models, integrating estimates of forest resilience into the paleoclimatic assessment is critically important to understanding the past and future role of drought in this landscape.This project will provide information useful in managing Amazonian ecosystem services in the face of climate variability and change, via scientific publications as well as reports to Amazonian policy-makers and managers in their native languages. The team is building on inter-institutional ties within the US and also forming new partnerships in Amazonia. The team will also create two new mechanisms for explaining the Amazon's climate challenge and key paleo-perspectives to the public, including students and non-English speakers: (1) a new exhibit at the largest live rainforest exhibit in the US, and (2) a contest to produce the best short multi-lingual video on the science and its implications. We will also train two paleoenvironmental Ph.D. scientists in this highly relevant interdisciplinary context, as well as several undergraduate students, including those from the large Hispanic and Native American student communities at the University of Arizona.

技术支持这笔赠款将提供改进的古气候和古干旱的角度需要管理亚马逊河流域面临的自然气候变异和变化。该项目的目标是在巴西，厄瓜多尔和秘鲁的三个集群的亚马逊河流域西部湖泊建立一个区域网络，至少有四个分十年解决1500年至3000年的古气候，植被和火灾历史的综合记录亚马逊河流域西部。该团队将使用气候和地球系统建模策略来解决许多问题，包括：* 每个湖泊记录中假设的干旱事件在多大程度上真正干旱，即，在附近的其他湖泊记录（有限干旱）和1,000公里以外的其他湖泊记录（更广泛的干旱）中重现？*对亚马逊河流域干旱和突变风险的最佳“古信息”估计是什么？*亚马逊河流域的植被和火灾动态对过去干旱严重程度的反应如何，这些生物物理反馈如何影响未来的森林可持续性和临界点的风险？在亚马逊河动力系统接近临界转变时是否有预警行为？最先进的模型模拟观测到的干旱和突变记录的效果如何？*什么是占主导地位的控制十年到百年尺度的干旱变率和突然的水文气候变化在亚马逊河流域？2005年，亚马逊流域遭受了仪器观测时期前所未有的干旱。科学家们很快意识到这场干旱是一个新的威胁，它使亚马逊河流域的生物多样性、作为碳汇的能力和生态系统服务（例如，水文和经济）处于危险之中。2010年，发生了第二次更严重的干旱。有人认为，亚马逊河流域可能无法在加速的气候变化中生存下来，甚至可能达到一个临界点，超过这个临界点，大部分森林将不可逆转地转化为稀树草原。亚利桑那大学和佛罗里达理工学院的研究小组收集的数据显示，亚马逊河流域一年一次的严重干旱并不罕见，而且还发生了更长的多年（长达15年）干旱和气候突变。这1500年的记录与最先进的气候模型模拟之间的比较也表明，模型可能低估了亚马逊河流域未来长期干旱的风险。由于碳反馈是现代完全耦合气候模型的重要组成部分，因此将森林复原力估计纳入古气候评估对于了解干旱在这一景观中的过去和未来作用至关重要。通过科学出版物以及向亚马逊决策者和管理人员提供的母语报告，该团队正在美国建立机构间联系，并在亚马逊地区建立新的合作伙伴关系。该团队还将创建两个新机制，向公众（包括学生和非英语母语者）解释亚马逊的气候挑战和关键的古观点：（1）在美国最大的热带雨林展览中举办新展览，（2）制作关于科学及其影响的最佳多语言短片的竞赛。我们还将培养两名古环境博士。在这个高度相关的跨学科背景下，科学家，以及几个本科生，包括来自亚利桑那大学的大型西班牙裔和美洲原住民学生社区。