Fast Response of Amazon Rivers to Quaternary Climate Cycles
Name
JGR Earth Surface - 2021 - Goldberg - Fast Response of Amazon Rivers to Quaternary Climate Cycles.pdf
Description
Published version
Size
3.28 MB
Format
Adobe PDF
Checksum (MD5)
f845c4517c24a597c71642129b80a808
Author(s)
Goldberg, Samuel L
Schmidt, Morgan J
Perron, J Taylor
Date Issued
November 18, 2021
Journal
Journal of Geophysical Research: Earth Surface
Publisher
American Geophysical Union
Citation
Goldberg, S. L., Schmidt, M. J., & Perron, J. T. (2021). Fast response of Amazon rivers to Quaternary climate cycles. Journal of Geophysical Research: Earth Surface, 126, e2021JF006416.
Version
Final published version
Abstract
Large alluvial rivers transport water and sediment across continents and shape lowland landscapes. Repeated glacial cycles have dominated Earth's recent climate, but it is unclear whether these rivers are sensitive to such rapid changes. The Amazon River system, the largest and highest‐discharge in the world, features extensive young terraces that demonstrate geologically rapid change temporally correlated with changes in runoff from Quaternary climate cycles. To test the plausibility of a causal relationship, we use a simple model to estimate from empirical measurements how quickly a river profile responds to changes in discharge or sediment supply. Applying this model to data from 30 gauging stations along alluvial rivers throughout the Brazilian Amazon, we find that many rivers of the Amazon basin can respond faster than glacially induced changes in runoff or sediment flux. The Amazon basin is unusually responsive compared to other large river systems due to its high discharge and sediment flux, narrow floodplains, and low slopes. As a result, we predict that the Amazon basin has been highly dynamic during Quaternary glacial cycles, with cyclical aggradation and incision of lowland rivers driving repeated habitat and environmental change throughout the region. This dynamic landscape may have contributed to the exceptional biodiversity of the region and patterns of ancient human settlement.
MIT Department
Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
10.1029/2021jf006416
