Global Methane Budget 2000–2020 DOI Creative Commons
Marielle Saunois, Adrien Martinez, Benjamin Poulter

et al.

Earth system science data, Journal Year: 2025, Volume and Issue: 17(5), P. 1873 - 1958

Published: May 9, 2025

Abstract. Understanding and quantifying the global methane (CH4) budget is important for assessing realistic pathways to mitigate climate change. CH4 second most human-influenced greenhouse gas in terms of forcing after carbon dioxide (CO2), both emissions atmospheric concentrations have continued increase since 2007 a temporary pause. The relative importance compared those CO2 temperature change related its shorter lifetime, stronger radiative effect, acceleration growth rate over past decade, causes which are still debated. Two major challenges factors responsible observed arise from diverse, geographically overlapping sources uncertain magnitude temporal destruction by short-lived highly variable hydroxyl radicals (OH). To address these challenges, we established consortium multidisciplinary scientists under umbrella Global Carbon Project improve, synthesise, update regularly stimulate new research on cycle. Following Saunois et al. (2016, 2020), present here third version living review paper dedicated decadal budget, integrating results top-down emission estimates (based situ Greenhouse Gases Observing SATellite (GOSAT) observations an ensemble inverse-model results) bottom-up process-based models estimating land surface chemistry, inventories anthropogenic emissions, data-driven extrapolations). We recent 2010–2019 calendar decade (the latest period full data sets available), previous 2000–2009 year 2020. revision this 2025 edition benefits progress inland freshwater with better counting lakes ponds, reservoirs, streams rivers. This also reduces double across wetland and, first time, includes estimate potential that may exist (average 23 Tg yr−1). Bottom-up approaches show combined average 248 [159–369] yr−1 decade. Natural fluxes perturbed human activities through climate, eutrophication, use. In estimate, component contributing emissions. Newly available gridded products allowed us derive almost complete latitudinal regional based approaches. For estimated inversions (top-down) be 575 (range 553–586, corresponding minimum maximum model ensemble). Of amount, 369 or ∼ 65 % attributed direct fossil, agriculture, waste biomass burning 350–391 63 %–68 %). period, give slightly lower total than 2010–2019, 32 9–40). 2020 highest reaches 608 581–627), 12 higher 2000s. Since 2012, trends been tracking scenarios assume no minimal mitigation policies proposed Intergovernmental Panel Climate Change (shared socio-economic SSP5 SSP3). methods suggest 16 (94 yr−1) larger (669 yr−1, range 512–849) inversion period. discrepancy between budgets has greatly reduced differences (167 156 2020) respectively), time uncertainties overlap. Although bottom-up, source uncertainty attributable natural especially wetlands freshwaters. tropospheric loss methane, as main contributor at 563 [510–663] chemistry–climate models. These values due impact rise remaining large (∼ 25 sink 633 [507–796] 554 [550–567] However, use same OH distribution, introduces less likely justified. agriculture contributed 228 [213–242] 211 [195–231] budget. Fossil fuel 115 [100–124] 120 [117–125] Biomass biofuel 27 [26–27] 28 [21–39] identify five priorities improving budget: (i) producing global, high-resolution map water-saturated soils inundated areas emitting robust classification different types ecosystems; (ii) further development inland-water emissions; (iii) intensification local (e.g. FLUXNET-CH4 measurements, urban-scale monitoring, satellite imagery pointing capabilities) scales (surface networks remote sensing measurements satellites) constrain inversions; (iv) improvements transport representation photochemical sinks (v) integration 3D variational systems using isotopic and/or co-emitted species such ethane well information super-emitters detected (mainly oil sector but coal, landfills) improve partitioning. presented can downloaded https://doi.org/10.18160/GKQ9-2RHT (Martinez al., 2024).

Language: Английский

Greenhouse Gas Budgets of Central and West Asia (2000–2020): A Significant Net Source to the Atmosphere DOI Creative Commons

Xiaoyu Qin,

Hanqin Tian, Josep G. Canadell

et al.

Global Biogeochemical Cycles, Journal Year: 2025, Volume and Issue: 39(3)

Published: Feb. 27, 2025

Abstract This study provides the first comprehensive quantification of three major greenhouse gases (GHGs, including CO 2 , CH 4 and N O) budgets for Central West Asia (CWA) from 2000 to 2020, contributions fossil fuels, industry, managed unmanaged terrestrial ecosystems. We use bottom‐up (BU: inventories process‐based models) top‐down approaches (TD: atmospheric inversions) elucidate CWA's GHG budget its changes. BU TD consistently show that CWA was a significant growing source during 2010s: average net emissions were 4,175 (range: 4,055–4,301) Tg eq yr −1 based on using global warming potentials over 100‐year period (GWP100), slightly higher 4,293 (3,760–4,826) TD. estimates fuel combustion fugitive releases dominant source, accounting 61% total in 2010s, with 2,554 (2,526–2,582) . Terrestrial natural ecosystems weak sink sources O, which together resulted decadal mean emission 220.5 (114.5–332.8) Non‐CO gases, primarily contributed significantly region's emissions, 32% (BU) 24% (TD) under GWP100, increasing 57% 49% GWP20, highlighting stronger impact shorter timescales. Overall, about 8% 10% 7% 3% O.

Language: Английский

Citations

0
Global Methane Budget 2000–2020 DOI Creative Commons
Marielle Saunois, Adrien Martinez, Benjamin Poulter

et al.

Earth system science data, Journal Year: 2025, Volume and Issue: 17(5), P. 1873 - 1958

Published: May 9, 2025

Abstract. Understanding and quantifying the global methane (CH4) budget is important for assessing realistic pathways to mitigate climate change. CH4 second most human-influenced greenhouse gas in terms of forcing after carbon dioxide (CO2), both emissions atmospheric concentrations have continued increase since 2007 a temporary pause. The relative importance compared those CO2 temperature change related its shorter lifetime, stronger radiative effect, acceleration growth rate over past decade, causes which are still debated. Two major challenges factors responsible observed arise from diverse, geographically overlapping sources uncertain magnitude temporal destruction by short-lived highly variable hydroxyl radicals (OH). To address these challenges, we established consortium multidisciplinary scientists under umbrella Global Carbon Project improve, synthesise, update regularly stimulate new research on cycle. Following Saunois et al. (2016, 2020), present here third version living review paper dedicated decadal budget, integrating results top-down emission estimates (based situ Greenhouse Gases Observing SATellite (GOSAT) observations an ensemble inverse-model results) bottom-up process-based models estimating land surface chemistry, inventories anthropogenic emissions, data-driven extrapolations). We recent 2010–2019 calendar decade (the latest period full data sets available), previous 2000–2009 year 2020. revision this 2025 edition benefits progress inland freshwater with better counting lakes ponds, reservoirs, streams rivers. This also reduces double across wetland and, first time, includes estimate potential that may exist (average 23 Tg yr−1). Bottom-up approaches show combined average 248 [159–369] yr−1 decade. Natural fluxes perturbed human activities through climate, eutrophication, use. In estimate, component contributing emissions. Newly available gridded products allowed us derive almost complete latitudinal regional based approaches. For estimated inversions (top-down) be 575 (range 553–586, corresponding minimum maximum model ensemble). Of amount, 369 or ∼ 65 % attributed direct fossil, agriculture, waste biomass burning 350–391 63 %–68 %). period, give slightly lower total than 2010–2019, 32 9–40). 2020 highest reaches 608 581–627), 12 higher 2000s. Since 2012, trends been tracking scenarios assume no minimal mitigation policies proposed Intergovernmental Panel Climate Change (shared socio-economic SSP5 SSP3). methods suggest 16 (94 yr−1) larger (669 yr−1, range 512–849) inversion period. discrepancy between budgets has greatly reduced differences (167 156 2020) respectively), time uncertainties overlap. Although bottom-up, source uncertainty attributable natural especially wetlands freshwaters. tropospheric loss methane, as main contributor at 563 [510–663] chemistry–climate models. These values due impact rise remaining large (∼ 25 sink 633 [507–796] 554 [550–567] However, use same OH distribution, introduces less likely justified. agriculture contributed 228 [213–242] 211 [195–231] budget. Fossil fuel 115 [100–124] 120 [117–125] Biomass biofuel 27 [26–27] 28 [21–39] identify five priorities improving budget: (i) producing global, high-resolution map water-saturated soils inundated areas emitting robust classification different types ecosystems; (ii) further development inland-water emissions; (iii) intensification local (e.g. FLUXNET-CH4 measurements, urban-scale monitoring, satellite imagery pointing capabilities) scales (surface networks remote sensing measurements satellites) constrain inversions; (iv) improvements transport representation photochemical sinks (v) integration 3D variational systems using isotopic and/or co-emitted species such ethane well information super-emitters detected (mainly oil sector but coal, landfills) improve partitioning. presented can downloaded https://doi.org/10.18160/GKQ9-2RHT (Martinez al., 2024).

Language: Английский

Citations

0