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

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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.