作者
Jan C. Minx,William F. Lamb,Robbie M. Andrew,Josep G. Canadell,Monica Crippa,Niklas Döbbeling,Piers M. Forster,Diego Guizzardi,Jos Olivier,Glen P. Peters,Julia Pongratz,Andy Reisinger,Matthew Rigby,Marielle Saunois,Steven J. Smith,Efisio Solazzo,Hanqin Tian
摘要
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
CO 2 emissions, CH 4 emissions, N 2 O emissions, as well as those from fluorinated gases (F-gases: HFCs, PFCs, SF 6 , NF 3 ) 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 CO 2 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 Gt CO2 eq.
consisting of CO 2 from fossil fuel combustion and industry (FFI) 38 ± 3.0 GtCO 2 , CO 2 -LULUCF 5.7 ± 4.0 GtCO 2 , CH 4 10 ± 3.1 Gt CO2 eq. , N 2 O
2.6 ± 1.6 Gt CO2 eq. , and F-gases 1.3 ± 0.40 Gt CO2 eq. Initial estimates suggest further growth of 1.3 Gt CO2 eq. in GHG emissions to reach 59 ± 6.6 Gt CO2 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 .