Integrating the evidence for a terrestrial carbon sink caused by increasing atmospheric CO2 Walker, Anthony P. De Kauwe, Martin G. Bastos, Ana Belmecheri, Soumaya Georgiou, Katerina Keeling, Ralph F. McMahon, Sean M. Medlyn, Belinda E. Moore, David J. P. Norby, Richard J. Zaehle, Sönke Anderson‐Teixeira, Kristina J. Battipaglia, Giovanna Brienen, Roel J. W. Cabugao, Kristine G. Cailleret, Maxime Campbell, Elliott Canadell, Josep G. Ciais, Philippe Craig, Matthew E. Ellsworth, David S. Farquhar, Graham D. Fatichi, Simone Fisher, Joshua B. Frank, David C. Graven, Heather Gu, Lianhong Haverd, Vanessa Heilman, Kelly Heimann, Martin Hungate, Bruce A. Iversen, Colleen M. Joos, Fortunat Jiang, Mingkai Keenan, Trevor F. Knauer, Jürgen Körner, Christian Leshyk, Victor O. Leuzinger, Sebastian Liu, Yao MacBean, Natasha Malhi, Yadvinder McVicar, Tim R. Penuelas, Josep Pongratz, Julia Powell, A. Shafer Riutta, Terhi Sabot, Manon E. B. Schleucher, Juergen Sitch, Stephen Smith, William K. Sulman, Benjamin Taylor, Benton Terrer, César Torn, Margaret S. Treseder, Kathleen K. Trugman, Anna T. Trumbore, Susan E. van Mantgem, Phillip J. Voelker, Steve L. Whelan, Mary E. Zuidema, Pieter A. Beta factor Carbon dioxide CO2 fertilization CO2-fertilization hypothesis Free-air CO2 enrichment (FACE) Global carbon cycle Land–atmosphere feedback Terrestrial ecosystems Atmospheric carbon dioxide concentration ([CO 2 ]) is increasing, which increases leaf-scalephotosynthesis and intrinsic water-use efficiency. These direct responses have the potential toincrease plant growth, vegetation biomass, and soil organic matter; transferring carbon from theatmosphere into terrestrial ecosystems (a carbon sink). A substantial global terrestrial carbon sinkwould slow the rate of [CO 2] increase and thus climate change. However, ecosystem CO2responses are complex or confounded by concurrent changes in multiple agents of global changeand evidence for a [CO 2]-driven terrestrial carbon sink can appear contradictory. Here wesynthesize theory and broad, multidisciplinary evidence for the effects of increasing [CO 2](iCO 2) on the global terrestrial carbon sink. Evidence suggests a substantial increase in globalphotosynthesis since pre-industrial times. Established theory, supported by experiments,indicates that iCO 2 is likely responsible for about half of the increase. Global carbon budgeting,atmospheric data, and forest inventories indicate a historical carbon sink, and these apparentiCO 2 responses are high in comparison to experiments and predictions from theory. Plantmortality and soil carbon iCO 2 responses are highly uncertain. In conclusion, a range of evidencesupports a positive terrestrial carbon sink in response to iCO2 , albeit with uncertain magnitudeand strong suggestion of a role for additional agents of global change. Wiley 2021 info:eu-repo/semantics/article doc-type:article text http://purl.org/coar/resource_type/c_2df8fbb1 https://research-explorer.ista.ac.at/record/22570 Walker AP, De Kauwe MG, Bastos A, et al. Integrating the evidence for a terrestrial carbon sink caused by increasing atmospheric CO2. <i>New Phytologist</i>. 2021;229(5):2413-2445. doi:<a href="https://doi.org/10.1111/nph.16866">10.1111/nph.16866</a> eng info:eu-repo/semantics/altIdentifier/doi/10.1111/nph.16866 info:eu-repo/semantics/altIdentifier/issn/0028-646X info:eu-repo/semantics/altIdentifier/e-issn/1469-8137 info:eu-repo/semantics/altIdentifier/pmid/32789857 info:eu-repo/semantics/openAccess