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

University Of Arkansas, Fayetteville AR

Investigators

Abstract

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 regimes The 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.