Abstract

Abstract. To track progress towards keeping global warming well below 2 ∘C or even 1.5 ∘C, as agreed in the Paris Agreement, comprehensive up-to-date and reliable information on anthropogenic emissions and removals of greenhouse gas (GHG) emissions is required. Here we compile a new synthetic dataset on anthropogenic GHG emissions for 1970–2018 with a fast-track extension to 2019. Our dataset is global in coverage and includes CO2 emissions, CH4 emissions, N2O emissions, as well as those from fluorinated gases (F-gases: HFCs, PFCs, SF6, NF3) and provides country and sector details. We build this dataset from the version 6 release of the Emissions Database for Global Atmospheric Research (EDGAR v6) and three bookkeeping models for CO2 emissions from land use, land-use change, and forestry (LULUCF). We assess the uncertainties of global greenhouse gases at the 90 % confidence interval (5th–95th percentile range) by combining statistical analysis and comparisons of global emissions inventories and top-down atmospheric measurements with an expert judgement informed by the relevant scientific literature. We identify important data gaps for F-gas emissions. The agreement between our bottom-up inventory estimates and top-down atmospheric-based emissions estimates is relatively close for some F-gas species (∼ 10 % or less), but estimates can differ by an order of magnitude or more for others. Our aggregated F-gas estimate is about 10 % lower than top-down estimates in recent years. However, emissions from excluded F-gas species such as chlorofluorocarbons (CFCs) or hydrochlorofluorocarbons (HCFCs) are cumulatively larger than the sum of the reported species. Using global warming potential values with a 100-year time horizon from the Sixth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC), global GHG emissions in 2018 amounted to 58 ± 6.1 GtCO2 eq. consisting of CO2 from fossil fuel combustion and industry (FFI) 38 ± 3.0 GtCO2, CO2-LULUCF 5.7 ± 4.0 GtCO2, CH4 10 ± 3.1 GtCO2 eq., N2O 2.6 ± 1.6 GtCO2 eq., and F-gases 1.3 ± 0.40 GtCO2 eq. Initial estimates suggest further growth of 1.3 GtCO2 eq. in GHG emissions to reach 59 ± 6.6 GtCO2 eq. by 2019. Our analysis of global trends in anthropogenic GHG emissions over the past 5 decades (1970–2018) highlights a pattern of varied but sustained emissions growth. There is high confidence that global anthropogenic GHG emissions have increased every decade, and emissions growth has been persistent across the different (groups of) gases. There is also high confidence that global anthropogenic GHG emissions levels were higher in 2009–2018 than in any previous decade and that GHG emissions levels grew throughout the most recent decade. While the average annual GHG emissions growth rate slowed between 2009 and 2018 (1.2 % yr−1) compared to 2000–2009 (2.4 % yr−1), the absolute increase in average annual GHG emissions by decade was never larger than between 2000–2009 and 2009–2018. Our analysis further reveals that there are no global sectors that show sustained reductions in GHG emissions. There are a number of countries that have reduced GHG emissions over the past decade, but these reductions are comparatively modest and outgrown by much larger emissions growth in some developing countries such as China, India, and Indonesia. There is a need to further develop independent, robust, and timely emissions estimates across all gases. As such, tracking progress in climate policy requires substantial investments in independent GHG emissions accounting and monitoring as well as in national and international statistical infrastructures. The data associated with this article (Minx et al., 2021) can be found at https://doi.org/10.5281/zenodo.5566761.

Highlights

  • By signing the Paris Agreement, countries acknowledged the necessity of keeping the most severe climate change risks in check by limiting warming to well below 2 ◦C and pursuing efforts to limit warming to 1.5 ◦C (UNFCCC, 2015)

  • While average annual emissions of all greenhouse gas (GHG) together grew by about 75 % from 31 ± 4.3 GtCO2 eq yr−1 during the 1970s (1970–1979) to 55 ± 5.9 GtCO2 eq yr−1 during the most recent decade (2009–2018), CO2-fossil fuel combustion and industry (FFI) emissions doubled from 18 ± 1.4 to 36 ± 2.9 GtCO2 eq yr−1 and fluorinated gases (F-gases) grew almost 5-fold from 0.19 ± 0.057 to 1.1 ± 0.34 GtCO2 eq yr−1 across the same time period

  • Persistent and fast growth in F-gas emissions has resulted in emissions levels that are tracking at about 1.3 ± 0.40 GtCO2 eq yr−1 in 2018 – 2.3 % of total GHG emissions measured as global warming potentials (GWPs)-100

Read more

Summary

Introduction

By signing the Paris Agreement, countries acknowledged the necessity of keeping the most severe climate change risks in check by limiting warming to well below 2 ◦C and pursuing efforts to limit warming to 1.5 ◦C (UNFCCC, 2015) This requires rapid and sustained greenhouse gas (GHG) emissions reductions towards net zero carbon dioxide (CO2) emissions well within the 21st century along with deep reductions in non-CO2 emissions (Rogelj et al, 2015; IPCC, 2018). While there is a growing number of global emissions inventories, only a few of them provide a wide coverage of gases, sectors, activities, and countries or regions that are sufficiently up to date to comprehensively track progress and thereby aid discussions in science and policy. Many still lack a well-developed statistical infrastructure to provide detailed reports (Janssens-Maenhout et al, 2019)

Methods
Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.