Global Carbon Budget 2022

• DOI: 10.5194/essd-14-4811-2022
• Publication Date: 2022-11-11T00:00:03Z
• Authors: Pierre Friedlings...; Michael O'Sullivan; Matthew W. Jones; Robbie M. Andrew; Luke Gregor; Judith Hauck; Corinne Le Quéré; Ingrid T. Luijkx; Are Olsen; Glen P. Peters; Wouter Peters; Julia Pongratz; Clemens Schwingsh...; Stephen Sitch; Josep G. Canadell; Philippe Ciais; Robert B. Jackson; Simone R. Alin; Ramdane Alkama; Almut Arneth; Vivek K. Arora; Nicholas R. Bates; Meike Becker; Nicolas Bellouin; Henry C. Bittig; Laurent Bopp; Frédéric Chevallier; Louise P. Chini; Margot Cronin; Wiley Evans; Stefanie Falk; Richard A. Feely; Thomas Gasser; Marion Gehlen; Thanos Gkritzalis; Lucas Gloege; Giacomo Grassi; Nicolas Gruber; Özgür Gürses; Ian Harris; Matthew Hefner; Richard A. Houghton; George C. Hurtt; Yosuke Iida; Tatiana Ilyina; Atul K. Jain; Annika Jersild; Koji Kadono; Etsushi Kato; Daniel Kennedy; Kees Klein Goldewijk; Jürgen Knauer; Jan Ivar Korsbakken; Peter Landschützer; Nathalie Lefèvre; Keith Lindsay; Junjie Liu; Zhu Liu; Gregg Marland; Nicolas Mayot; Matthew J. McGrath; Nicolas Metzl; Natalie M. Monacci; David R. Munro; Shin-Ichiro Nakaoka; Yosuke Niwa; Kevin O'Brien; Tsuneo Ono; Paul I. Palmer; Naiqing Pan; Denis Pierrot; Katie Pocock; Benjamin Poulter; Laure Resplandy; Eddy Robertson; Christian Rödenbeck; Carmen Rodriguez; Thais M. Rosan; Jörg Schwinger; Roland Séférian; Jamie D. Shutler; Ingunn Skjelvan; Tobias Steinhoff; Qing Sun; Adrienne J. Sutton; Colm Sweeney; Shintaro Takao; Toste Tanhua; Pieter P. Tans; Xiangjun Tian; Hanqin Tian; Bronte Tilbrook; Hiroyuki Tsujino; Francesco Tubiello; Guido R. van der ...; Anthony P. Walker; Rik Wanninkhof; Chris Whitehead; Anna Willstrand W...; Rebecca Wright; Wenping Yuan; Chao Yue; Xu Yue; Sönke Zaehle; Jiye Zeng; Bo Zheng
• Keywords: 0301 basic medicine; 550; [SDE.MCG]Environmental Sciences/Global Changes; Oceanografi, hydrologi och vattenresurser; 01 natural sciences; 7. Clean energy; 333; 12. Responsible consumption; Oceanography, Hydrology and Water Resources; 03 medical and health sciences; 11. Sustainability; SDG 13 - Climate Action; Life Science; SDG 15 - Life on Land; 0105 earth and related environmental sciences; info:eu-repo/classification/ddc/550; ddc:550; 15. Life on land; Earth sciences; [SDE.MCG] Environmental Sciences/Global Changes; 13. Climate action; NA; 370203 - Greenhouse gas inventories and fluxes

Abstract. Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere in a changing climate is critical to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe and synthesize data sets and methodologies to quantify the five major components of the global carbon budget and their uncertainties. Fossil CO2 emissions (EFOS) are based on energy statistics and cement production data, while emissions from land-use change (ELUC), mainly deforestation, are based on land use and land-use change data and bookkeeping models. Atmospheric CO2 concentration is measured directly, and its growth rate (GATM) is computed from the annual changes in concentration. The ocean CO2 sink (SOCEAN) is estimated with global ocean biogeochemistry models and observation-based data products. The terrestrial CO2 sink (SLAND) is estimated with dynamic global vegetation models. The resulting carbon budget imbalance (BIM), the difference between the estimated total emissions and the estimated changes in the atmosphere, ocean, and terrestrial biosphere, is a measure of imperfect data and understanding of the contemporary carbon cycle. All uncertainties are reported as ±1σ. For the year 2021, EFOS increased by 5.1 % relative to 2020, with fossil emissions at 10.1 ± 0.5 GtC yr−1 (9.9 ± 0.5 GtC yr−1 when the cement carbonation sink is included), and ELUC was 1.1 ± 0.7 GtC yr−1, for a total anthropogenic CO2 emission (including the cement carbonation sink) of 10.9 ± 0.8 GtC yr−1 (40.0 ± 2.9 GtCO2). Also, for 2021, GATM was 5.2 ± 0.2 GtC yr−1 (2.5 ± 0.1 ppm yr−1), SOCEAN was 2.9 ± 0.4 GtC yr−1, and SLAND was 3.5 ± 0.9 GtC yr−1, with a BIM of −0.6 GtC yr−1 (i.e. the total estimated sources were too low or sinks were too high). The global atmospheric CO2 concentration averaged over 2021 reached 414.71 ± 0.1 ppm. Preliminary data for 2022 suggest an increase in EFOS relative to 2021 of +1.0 % (0.1 % to 1.9 %) globally and atmospheric CO2 concentration reaching 417.2 ppm, more than 50 % above pre-industrial levels (around 278 ppm). Overall, the mean and trend in the components of the global carbon budget are consistently estimated over the period 1959–2021, but discrepancies of up to 1 GtC yr−1 persist for the representation of annual to semi-decadal variability in CO2 fluxes. Comparison of estimates from multiple approaches and observations shows (1) a persistent large uncertainty in the estimate of land-use change emissions, (2) a low agreement between the different methods on the magnitude of the land CO2 flux in the northern extratropics, and (3) a discrepancy between the different methods on the strength of the ocean sink over the last decade. This living data update documents changes in the methods and data sets used in this new global carbon budget and the progress in understanding of the global carbon cycle compared with previous publications of this data set. The data presented in this work are available at https://doi.org/10.18160/GCP-2022 (Friedlingstein et al., 2022b).