Emerging negative impact of warming on summer carbon uptake in northern ecosystems

• Published in: Nature Communications
• Main Authors: Wang, Tao, Liu, Dan, Piao, Shilong, Wang, Yilong, Wang, Xiaoyi, Guo, Hui, Lian, Xu, Burkhart, John, Ciais, Philippe, Huang, Mengtian, Janssens, Ivan, Li, Yue, Liu, Yongwen, Peñuelas, Josep, Peng, Shushi, Yang, Hui, Yao, Yitong, Yin, Yi, Zhao, Yutong
• Other Authors: Chinese Academy of Sciences Beijing (CAS), Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Modélisation INVerse pour les mesures atmosphériques et SATellitaires (SATINV), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Department of Geosciences Oslo, Faculty of Mathematics and Natural Sciences Oslo, University of Oslo (UiO)-University of Oslo (UiO), ICOS-ATC (ICOS-ATC), Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University Beijing, UNIVERSITY OF ANTWERP DEPARTMENT OF BIOLOGY ANTWERPEN BEL, Partenaires IRSTEA, Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), CREAF - Centre for Ecological Research and Applied Forestries
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2018
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; Barrow; Point Barrow; Alaska
• Online Access: https://hal.archives-ouvertes.fr/hal-02975867; https://hal.archives-ouvertes.fr/hal-02975867/document; https://hal.archives-ouvertes.fr/hal-02975867/file/s41467-018-07813-7.pdf; https://doi.org/10.1038/s41467-018-07813-7

International audience Most studies of the northern hemisphere carbon cycle based on atmospheric CO 2 concentration have focused on spring and autumn, but the climate change impact on summer carbon cycle remains unclear. Here we used atmospheric CO 2 record from Point Barrow (Alaska) to show that summer CO 2 drawdown between July and August, a proxy of summer carbon uptake, is significantly negatively correlated with terrestrial temperature north of 50°N interannually during 1979-2012. However, a refined analysis at the decadal scale reveals strong differences between the earlier (1979-1995) and later (1996-2012) periods, with the significant negative correlation only in the later period. This emerging negative temperature response is due to the disappearance of the positive temperature response of summer vegetation activities that prevailed in the earlier period. Our finding, together with the reported weakening temperature control on spring carbon uptake, suggests a diminished positive effect of warming on high-latitude carbon uptake.