Abstract

In 2023, an intense drought impacted the Amazon basin triggered by climate change and a strong El Niño event, with the Negro River reaching its lowest water level in 120 years. However, the spatiotemporal open water extent (OWE) during this drought remains unclear. This study comprehensively evaluates OWE variability in the central Amazon using Sentinel-1 synthetic aperture radar (SAR) data since 2017. Monthly OWE masks were generated through an empirical threshold classification with accuracy >95%. Overall, the central Amazon experienced a reduction of ∼8% in OWE in the 2023 dry season months (November and December) when compared to monthly-average. However, reductions of up to 80% in OWE were observed in several specific lakes. Our analysis underscores the unprecedented severity of the 2023/2024 drought on rivers and floodplains. Utilizing SAR remote sensing technologies, this study emphasizes the urgent need for proactive conservation measures to safeguard the Amazon’s ecological integrity amid escalating environmental challenges. Monthly water masks from January/2017 to September/2024 are available here: https://doi.org/10.5281/zenodo.12751783.

Details

Title
Sentinel-1 data reveals unprecedented reduction of open water extent due to 2023-2024 drought in the central Amazon basin
Author
Maciel, Daniel A 1   VIAFID ORCID Logo  ; Lousada, Fellipe 2 ; Fassoni-Andrade, Alice 3   VIAFID ORCID Logo  ; Renata Pacheco Quevedo 4   VIAFID ORCID Logo  ; Claudio Clemente Faria Barbosa 1   VIAFID ORCID Logo  ; Paule-Bonnet, Marie 5   VIAFID ORCID Logo  ; Evlyn Márcia Leão de Moraes Novo 1   VIAFID ORCID Logo 

1  Earth Observation and Geoinformatics Division, National Institute for Space Research (INPE) , São José dos Campos, SP, Brazil; Instrumentation Laboratory for Aquatic Systems (LabISA), Earth Observation Coordination of National Institute for Space Research (INPE) , São José dos Campos, SP, Brazil 
2  Earth Observation and Geoinformatics Division, National Institute for Space Research (INPE) , São José dos Campos, SP, Brazil; Instrumentation Laboratory for Aquatic Systems (LabISA), Earth Observation Coordination of National Institute for Space Research (INPE) , São José dos Campos, SP, Brazil; Technological University of Uruguay (UTEC)—Francisco Antonio Maciel s/n esq. Luis Morquio , Durazno, Uruguay 
3  Instituto de Geociências, Universidade de Brasília , Brasília, Brazil 
4  Department of Structural and Geotechnical Engineering, Polytechnic School of the University of São Paulo , Avenida Prof. Luciano Gualberto, Travessa do Politécnico 380, São Paulo, 05508-010 São Paulo, Brazil; Georisk and Environment Group, Geology Department, University of Liège , Liège, Belgium 
5  ESPACE-DEV, Univ Montpellier, IRD, Univ Antilles , Univ Guyane, Univ Réunion, 34093 Montpellier, France 
First page
124034
Publication year
2024
Publication date
Dec 2024
Publisher
IOP Publishing
e-ISSN
17489326
Source type
Scholarly Journal
Language of publication
English
DOI
https://doi.org/10.1088/1748-9326/ad8a71
ProQuest document ID
3128306204
Copyright
© 2024 The Author(s). Published by IOP Publishing Ltd. This work is published under https://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.