Ampuero A. auteur aut IRD Strikis N. M. auteur aut IRD Apaestegui J. auteur aut IRD Vuille M. auteur aut IRD Novello V. F. auteur aut IRD Espinoza J. C. auteur aut IRD Cruz F. W. auteur aut IRD Vonhof H. auteur aut IRD Mayta V. C. auteur aut IRD Martins V. T. S. auteur aut IRD Cordeiro R. C. auteur aut IRD Azevedo V. auteur aut IRD Sifeddine Abdelfettah auteur aut IRD text journalArticle eng text/pdf born digital access In the Amazon basin, intense precipitation recycling across the forest significantly modifies the isotopic composition of rainfall (delta O-18, delta D). In the tropical hydrologic cycle, such an effect can be identified through deuterium excess (dxs), yet it remains unclear what environmental factors control dxs, increasing the uncertainty of dxs-based paleoclimate reconstructions. Here we present a 4-year record of the isotopic composition of rainfall, monitored in the northwestern Amazon basin. We analyze the isotopic variations as a function of the air mass history, based on atmospheric back trajectory analyses, satellite observations of precipitation upstream, leaf area index, and simulated moisture recycling along the transport pathway. We show that the precipitation recycling in the forest exerts a significant control on the isotopic composition of precipitation in the northwestern Amazon basin, especially on dxs during the dry season (r = 0.71). Applying these observations to existing speleothem and pollen paleorecords, we conclude that winter precipitation increased after the mid-Holocene, as the expansion of the forest allowed for more moisture recycling. Therefore, forest effects should be considered when interpreting paleorecords of past precipitation changes. specialized PEROU ANDES AMAZONIE 021 072 126 125 4 e2019JD031445 [11 ] 2020 2169-897X https://www.documentation.ird.fr/hor/fdi:010078882 10.1029/2019jd031445 2169-897X [F B010078882] https://www.documentation.ird.fr/hor/fdi:010078882 https://www.documentation.ird.fr/intranet/publi/2020/04/010078882.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2020-05-19 2025-02-24 fdi:010078882 fre