Tree ring isotopes reveal an intensification of the hydrological cycle in the Amazon
journal contribution
posted on 2025-08-27, 10:36 authored by Bruno BL Cintra, Emanuel Gloor, Jessica CA Baker, Arnoud BoomArnoud Boom, Jochen Schöngart, Santiago Clerici, Kanhu Pattnayak, Roel JW Brienen<p dir="ltr">Over recent decades the Amazon region has been exposed to large-scale land-use changes and global warming. How these changes affect Amazonia’s hydrological cycle remains unclear as meteorological data are scarce. We use tree ring oxygen isotope records to confirm that the Amazon hydrological cycle has intensified since 1980. Diverging isotopic trends from terra firme and floodplain trees from distinct sites (approximately 1000 km apart) in Western Amazon indicate rainfall amounts increased during the wet season and decreased during the dry season at large-scale. Using the Rayleigh distillation model, we estimate that wet season rainfall increased by 15–22%, and dry season rainfall decreased by 8–13%. These diverging trends provide evidence, independent from existing climate records, that the seasonality of the hydrological cycle in the Amazon is increasing. Continuation of the observed trends will have a pervasive impact on Amazon forests and floodplain ecosystems, and strongly affect the livelihoods of the regional riverine communities.</p>
Funding
NOAA Air Resources Laboratory (ARL) for the provision of the HYSPLIT transport and dispersion model and/or READY website (https://www.ready.noaa.gov) used in this publication. This work is supported by: Conselho Nacional de Desenvolvimento Científico e Tecnológico—Brazil grant 457423/2014-5 (JS, BBLC). Conselho Nacional de Desenvolvimento Científico e Tecnológico—Brazil grant 311874/2017-7 and 311247/2021-0 (JS). Conselho Nacional de Desenvolvimento Científico e Tecnológico—Brazil grant 207400/2014-8 (BBLC).
Towards a Comprehensive Understanding of Changes in the Amazon Hydrological Cycle
Natural Environment Research Council
Find out more...The Amazon hydrological cycle: past, present and future
Natural Environment Research Council
Find out more...Climate Recovery and Adaptation potential of Forests in the Tropics
UK Research and Innovation
Find out more...Research Councils UK/Natural Environment Research Council grant IP−1424-0514 (MG, RJWB). Research Councils UK/Natural Environment Research Council grant IP−1314-0512 (MG, RJWB). Fundação de Amparo à Pesquisa do Estado do Amazonas – FAPEAM/Brazil grant 146/2015 (JS, BBLC)
History
Author affiliation
College of Science & Engineering Geography, Geology & EnvironmentVersion
- VoR (Version of Record)
