Underestimation of the Tambora effects in North American taiga ecosystems

• Published in: Environmental Research Letters
• Main Authors: Gennaretti, Fabio, Boucher, Etienne, Nicault, Antoine, Gea-Izquierdo, Guillermo, Arseneault, Dominique, Berninger, Frank, Savard, Martine, Begin, Christian, Guiot, Joel
• Other Authors: Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université du Québec à Montréal = University of Québec in Montréal (UQAM), Ecosystèmes continentaux et risques environnementaux (ECCOREV), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), INIA-CIFOR, Université du Québec à Rimouski (UQAR), Université d'Helsinki, Geological Survey of Canada Québec (GSC Québec), Geological Survey of Canada - Office (GSC), Natural Resources Canada (NRCan)-Natural Resources Canada (NRCan), European Project: 656896,H2020,H2020-MSCA-IF-2014,MAIDEN-SPRUCE(2015)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2018
• Subjects: tambora legacy; Eastern Canada; regional climate responses; terrestrial biosphere responses; forest demography; mechanistic understanding; process-based modeling; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; Canada; taiga
• Online Access: https://insu.hal.science/insu-02269675; https://insu.hal.science/insu-02269675/document; https://insu.hal.science/insu-02269675/file/2018-Gennarett_Environ_Res_Lett.pdf; https://doi.org/10.1088/1748-9326/aaac0c

International audience The Tambora eruption (1815 AD) was one of the major eruptions of the last two millennia and has noequivalents over the last two centuries. Here, we collected an extensive network of earlymeteorological time series, climate simulation data and numerous, well-replicated proxy records from Eastern Canada to analyze the strength and the persistence of the Tambora impact on the regional climate and forest processes. Our results show that the Tambora impacts on the terrestrial biosphere were stronger than previously thought, and not only affected tree growth and carbon uptake for a longer period than registered in the regional climate, but also determined forest demography and structure. Increased tree mortality, four times higher than the background level, indicates that the Tambora climatic impact propagated to influence the structure of the North American taiga for several decades.We also show that the Tambora signal is more persistent in observed data (temperature, river ice dynamics, forest growth, tree mortality) than in simulated ones (climate and forest-growth simulations), indicating that our understanding of the mechanisms amplifying volcanic perturbations on climates and ecosystems is still limited, notably in the North American taiga.