Effect of Manure and Urea Fertilization on Yield, Carbon Speciation and Greenhouse Gas Emissions from Vegetable Production Systems of Nigeria and Republic of Benin: A Phytotron Study

Fertility management techniques being promoted in sub-Saharan Africa (SSA) seek to grow indigenous vegetables economically and sustainably. This study was conducted in a phytotron chamber and compared yield, soil carbon (C) speciation and greenhouse gas (nitrous oxide (N2O) and carbon dioxide (CO2)) emissions from SSA soils of two ecoregions; the dry savanna (lna, Republic of Benin) and rainforest (Ife, Nigeria) cultivated with local amaranth (Amaranthus cruentus) under manure (5 t/ha) and/or urea (80 kg N/ha) fertilization. Vegetable yield ranged from 4331 kg/ha to 7900 kg/ha in the rainforest, RF, soils and 3165 kg/ha to 4821 kg/ha in the dry savanna, DS, soils. Yield in the urea treatment was slightly higher compared to the manure, and manure+urea treatment, but the difference was not statistically significant. Cumulative CO2 emissions over 21 days ranged from 497.06 to 579.47 g CO2-C/kg soil/day in the RF, and 322.96 to 624.97 g CO2-C/kg soil/day in the DS, while cumulative N2O emissions ranged from 60.53 to 220.86 mg N2O-N/kg soil/day in the RF, and 24.78 to 99.08 mg N2O-N/kg soil/day in the DS. In the RF samples, when compared to the use of urea alone, the combined use of manure and urea reduced N2O emissions but led to an increase in the DS samples. ATR-FTIR analysis showed that the combined use of manure and manure+urea increased the rate of microbial decomposition in the soils of the DS, but no such effect was observed in soils of the RF. We conclude that combining manure and urea fertilization has different effects on soils of the two ecoregions, and that RF farmers can reduce agricultural N2O emissions without compromising soil productivity and yield potential.

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Effect of Manure and Urea Fertilization on Yield, Carbon Speciation and Greenhouse Gas Emissions from Vegetable Production Systems of Nigeria and Republic of Benin: A Phytotron Study

10.20944/preprints202001.0175.v1 ◽

2020 ◽

Author(s):

Abimfoluwa Olaleye ◽

Derek Peak ◽

Akeem Shorunke ◽

Gurbir Dhillon ◽

Durodoluwa Oyedele ◽

...

Keyword(s):

Greenhouse Gas ◽

Co2 Emissions ◽

Sub Saharan Africa ◽

Yield Potential ◽

Soil Productivity ◽

N2o Emissions ◽

Urea Treatment ◽

Combined Use ◽

Republic Of Benin ◽

Urea Fertilization

Fertility management techniques being promoted in sub-Saharan Africa (SSA) seek to grow indigenous vegetables economically and sustainably. This study was conducted in a phytotron chamber and compared yield, soil carbon (C) speciation and greenhouse gas (nitrous oxide (N2O) and carbon dioxide (CO2)) emissions from SSA soils of two ecoregions; the dry savanna (lna, Republic of Benin) and rainforest (Ife, Nigeria) cultivated with local amaranth (Amaranthus cruentus) under manure (5 t/ha) and/or urea (80 kg N/ha) fertilization. Vegetable yield ranged from 1753 kg/ac to 3198kg/ac in the rainforest, RF, soils and 1281 kg/ac to 1951 kg/ac in the dry savanna, DS, soils. Yield in the urea treatment was slightly higher compared to the manure+urea treatment, but the difference was not statistically significant. Cumulative CO2 emissions over 21 days ranged from 497.06 to 579.47 g CO2 in the RF, and 322.96 to 624.97 g CO2 in the DS, while cumulative N2O emissions ranged from 60.53 to 220.86 mg N2O in the RF, and 24.78 to 99.08 mg N2O in the DS. In the RF samples, the combined use of manure and urea reduced CO2 and N2O emissions but led to an increase in the DS samples. ATR-FTIR analysis showed that the combined use of manure and urea increased the rate of microbial degradation in the soils of the DS, but no such effect was observed in soils of the RF. We conclude that combining manure and urea fertilization has different effects on soils of the two ecoregions, and that RF farmers can reduce agricultural emissions without compromising soil productivity and yield potential.

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Effect of Organic Amendment Addition on Soil Properties, Greenhouse Gas Emissions and Grape Yield in Semi-Arid Vineyard Agroecosystems

Agronomy ◽

10.3390/agronomy11081477 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1477

Author(s):

Antonio Marín-Martínez ◽

Alberto Sanz-Cobeña ◽

Mª Angeles Bustamante ◽

Enrique Agulló ◽

Concepción Paredes

Keyword(s):

Soil Fertility ◽

Soil Properties ◽

Greenhouse Gas ◽

Co2 Emissions ◽

Organic Amendments ◽

Organic N ◽

N2o Emissions ◽

The Impact ◽

Semi Arid ◽

Grape Yield

In semi-arid vineyard agroecosystems, highly vulnerable in the context of climate change, the soil organic matter (OM) content is crucial to the improvement of soil fertility and grape productivity. The impact of OM, from compost and animal manure, on soil properties (e.g., pH, oxidisable organic C, organic N, NH4+-N and NO3−-N), grape yield and direct greenhouse gas (GHG) emission in vineyards was assessed. For this purpose, two wine grape varieties were chosen and managed differently: with a rain-fed non-trellising vineyard of Monastrell, a drip-irrigated trellising vineyard of Monastrell and a drip-irrigated trellising vineyard of Cabernet Sauvignon. The studied fertiliser treatments were without organic amendments (C), sheep/goat manure (SGM) and distillery organic waste compost (DC). The SGM and DC treatments were applied at a rate of 4600 kg ha−1 (fresh weight, FW) and 5000 kg ha−1 FW, respectively. The use of organic amendments improved soil fertility and grape yield, especially in the drip-irrigated trellising vineyards. Increased CO2 emissions were coincident with higher grape yields and manure application (maximum CO2 emissions = 1518 mg C-CO2 m−2 d−1). In contrast, N2O emissions, mainly produced through nitrification, were decreased in the plots showing higher grape production (minimum N2O emissions = −0.090 mg N2O-N m−2 d−1). In all plots, the CH4 fluxes were negative during most of the experiment (−1.073−0.403 mg CH4-C m−2 d−1), indicating that these ecosystems can represent a significant sink for atmospheric CH4. According to our results, the optimal vineyard management, considering soil properties, yield and GHG mitigation together, was the use of compost in a drip-irrigated trellising vineyard with the grape variety Monastrell.

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Smallholder African farms in western Kenya have limited greenhouse gas fluxes

Biogeosciences Discussions ◽

10.5194/bgd-12-15301-2015 ◽

2015 ◽

Vol 12 (18) ◽

pp. 15301-15336 ◽

Cited By ~ 3

Author(s):

D. E. Pelster ◽

M. C. Rufino ◽

T. Rosenstock ◽

J. Mango ◽

G. Saiz ◽

...

Keyword(s):

Greenhouse Gas ◽

Crop Production ◽

Crop Yields ◽

N Uptake ◽

Ghg Emissions ◽

Sub Saharan Africa ◽

N2o Emissions ◽

Vegetation Types ◽

Western Kenya ◽

The Impact

Abstract. Few field studies examine greenhouse gas (GHG) emissions from African agricultural systems resulting in high uncertainty for national inventories. We provide here the most comprehensive study in Africa to date, examining annual CO2, CH4 and N2O emissions from 59 plots, across different vegetation types, field types and land classes in western Kenya. The study area consists of a lowland area (approximately 1200 m a.s.l.) rising approximately 600 m to a highland plateau. Cumulative annual fluxes ranged from 2.8 to 15.0 Mg CO2-C ha−1, −6.0 to 2.4 kg CH4-C ha−1 and −0.1 to 1.8 kg N2O-N ha−1. Management intensity of the plots did not result in differences in annual fluxes for the GHGs measured (P = 0.46, 0.67 and 0.14 for CO2, N2O and CH4 respectively). The similar emissions were likely related to low fertilizer input rates (≤ 20 kg ha−1). Grazing plots had the highest CO2 fluxes (P = 0.005); treed plots were a larger CH4 sink than grazing plots (P = 0.05); while N2O emissions were similar across vegetation types (P = 0.59). This case study is likely representative for low fertilizer input, smallholder systems across sub-Saharan Africa, providing critical data for estimating regional or continental GHG inventories. Low crop yields, likely due to low inputs, resulted in high (up to 67 g N2O-N kg−1 aboveground N uptake) yield-scaled emissions. Improving crop production through intensification of agricultural production (i.e. water and nutrient management) may be an important tool to mitigate the impact of African agriculture on climate change.

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Smallholder farms in eastern African tropical highlands have low soil greenhouse gas fluxes

Biogeosciences ◽

10.5194/bg-14-187-2017 ◽

2017 ◽

Vol 14 (1) ◽

pp. 187-202 ◽

Cited By ~ 18

Author(s):

David Pelster ◽

Mariana Rufino ◽

Todd Rosenstock ◽

Joash Mango ◽

Gustavo Saiz ◽

...

Keyword(s):

Greenhouse Gas ◽

Crop Production ◽

Crop Yields ◽

N Uptake ◽

Sub Saharan Africa ◽

N2o Emissions ◽

Vegetation Types ◽

Smallholder Farms ◽

Sub Saharan ◽

Ch4 And N2o

Abstract. Few field studies examine greenhouse gas (GHG) emissions from African agricultural systems, resulting in high uncertainty for national inventories. This lack of data is particularly noticeable in smallholder farms in sub-Saharan Africa, where low inputs are often correlated with low yields, often resulting in food insecurity as well. We provide the most comprehensive study in Africa to date, examining annual soil CO2, CH4 and N2O emissions from 59 smallholder plots across different vegetation types, field types and land classes in western Kenya. The study area consists of a lowland area (approximately 1200 m a.s.l.) rising approximately 600 m to a highland plateau. Cumulative annual fluxes ranged from 2.8 to 15.0 Mg CO2-C ha−1, −6.0 to 2.4 kg CH4-C ha−1 and −0.1 to 1.8 kg N2O-N ha−1. Management intensity of the plots did not result in differences in annual GHG fluxes measured (P = 0.46, 0.14 and 0.67 for CO2, CH4 and N2O respectively). The similar emissions were likely related to low fertilizer input rates (≤ 20 kg N ha−1). Grazing plots had the highest CO2 fluxes (P = 0.005), treed plots (plantations) were a larger CH4 sink than grazing plots (P = 0.05), while soil N2O emissions were similar across vegetation types (P = 0.59). This study is likely representative for low fertilizer input, smallholder systems across sub-Saharan Africa, providing critical data for estimating regional or continental GHG inventories. Low crop yields, likely due to low fertilization inputs, resulted in high (up to 67 g N2O-N kg−1 aboveground N uptake) yield-scaled emissions. Improvement of crop production through better water and nutrient management might therefore be an important tool in increasing food security in the region while reducing the climate footprint per unit of food produced.

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Impact of earthworm <i>Lumbricus terrestris</i> living sites on the greenhouse gas balance of no-till arable soil

Biogeosciences ◽

10.5194/bg-12-5481-2015 ◽

2015 ◽

Vol 12 (18) ◽

pp. 5481-5493 ◽

Cited By ~ 21

Author(s):

M. Nieminen ◽

T. Hurme ◽

J. Mikola ◽

K. Regina ◽

V. Nuutinen

Keyword(s):

Greenhouse Gas ◽

Co2 Emissions ◽

Field Measurements ◽

Lumbricus Terrestris ◽

N2o Emission ◽

N2o Emissions ◽

Consistent Difference ◽

Climatic Effects ◽

Greenhouse Gas Balance ◽

No Till

Abstract. We studied the effect of the deep-burrowing earthworm Lumbricus terrestris on the greenhouse gas (GHG) fluxes and global warming potential (GWP) of arable no-till soil using both field measurements and a controlled 15-week laboratory experiment. In the field, the emissions of nitrous oxide (N2O) and carbon dioxide (CO2) were on average 43 and 32 % higher in areas occupied by L. terrestris (the presence judged by the surface midden) than in adjacent, unoccupied areas (with no midden). The fluxes of methane (CH4) were variable and had no consistent difference between the midden and non-midden areas. Removing the midden did not affect soil N2O and CO2 emissions. The laboratory results were consistent with the field observations in that the emissions of N2O and CO2 were on average 27 and 13 % higher in mesocosms with than without L. terrestris. Higher emissions of N2O were most likely due to the higher content of mineral nitrogen and soil moisture under the middens, whereas L. terrestris respiration fully explained the observed increase in CO2 emissions in the laboratory. In the field, the significantly elevated macrofaunal densities in the vicinity of middens likely contributed to the higher emissions from areas occupied by L. terrestris. The activity of L. terrestris increased the GWP of field and laboratory soil by 50 and 18 %, but only 6 and 2 % of this increase was due to the enhanced N2O emission. Our results suggest that high N2O emissions commonly observed in no-till soils can partly be explained by the abundance of L. terrestris under no-till management and that L. terrestris can markedly regulate the climatic effects of different cultivation practises.

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Greenhouse gas and energy fluxes in a boreal peatland forest after clearcutting

10.5194/bg-2018-473 ◽

2018 ◽

Cited By ~ 2

Author(s):

Mika Korkiakoski ◽

Juha-Pekka Tuovinen ◽

Timo Penttilä ◽

Sakari Sarkkola ◽

Paavo Ojanen ◽

...

Keyword(s):

Heat Flux ◽

Greenhouse Gas ◽

Co2 Emissions ◽

Ecosystem Respiration ◽

Gross Primary Production ◽

Sensible Heat Flux ◽

Ground Vegetation ◽

N2o Emissions ◽

Energy Fluxes ◽

C Stocks

Abstract. The most common forest management method in Fennoscandia is rotation forestry including clearcutting and forest regeneration. In clearcutting, stem wood is removed and the logging residues are either removed or left on site. Clearcutting changes the microclimate and vegetation structure at the site, both of which impact the site's carbon balance. Peat soils with poor aeration and high carbon (C) densities are especially prone to such changes, and significant changes in C stocks and greenhouse gas exchange can be expected. We measured carbon dioxide (CO2) and energy fluxes with the eddy covariance method for two years (April 2016–March 2018) on a peatland drained for forestry. After the clearcutting, we observed a significant rise (23 cm) in the water table level. The site was also a large CO2 source (first year: 3086 ± 120 g CO2 m−2yr−1, second year: 2072 ± 141 g CO2 m−2 yr−1) after the clearcutting. These large CO2 emissions resulted from the collapse of gross primary production (GPP) following the removal of photosynthesizing trees and the decline of ground vegetation. During the second summer (June–August) after the clearcutting, GPP had already increased by 96 % and total ecosystem respiration decreased by 14 % from the previous summer. As a result, net CO2 emissions decreased during the second summer after clearcutting compared to the first one. The Bowen ratios were different in 2016 and 2017, starting at 2.6 in May 2016 and decreasing to less than 1.0 in August 2016, while in 2017 it varied mostly within 0.6–1.0. This was due to a 33 % decrease in the sensible heat flux and a 40 % increase in the latent heat flux from the 2016 values, probably due to the recovery of ground vegetation that increased evapotranspiration and albedo of the site. In addition to CO2 and energy fluxes, we measured methane (CH4) and nitrous oxide (N2O) fluxes with manual chambers. After the clearcutting, the site turned from a small CH4 sink into a small source and from N2O-neutral to a significant N2O source. Compared to the large CO2 emissions, the global warming potential (GWP100) of the CH4 emissions was negligible. Also, the GWP100 due to increased N2O emissions was less than 10 % of that of the CO2 emission change.

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Reviews and syntheses: Greenhouse gas emissions in natural and agricultural lands in sub-Saharan Africa: synthesis of available data and suggestions for further studies

Biogeosciences Discussions ◽

10.5194/bgd-12-16479-2015 ◽

2015 ◽

Vol 12 (19) ◽

pp. 16479-16526 ◽

Cited By ~ 6

Author(s):

D.-G. Kim ◽

A. D. Thomas ◽

D. Pelster ◽

T. S. Rosenstock ◽

A. Sanz-Cobena

Keyword(s):

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Ghg Emissions ◽

Sub Saharan Africa ◽

N2o Emissions ◽

Ghg Emission ◽

Agricultural Lands ◽

N Application ◽

Application Rates ◽

Sub Saharan

Abstract. This paper summarizes currently available data on greenhouse gas (GHG) emissions from African natural and agricultural lands, outlines the knowledge gaps and suggests future directions and strategies for GHG emission studies. GHG emission data were collected from 73 studies conducted in 22 countries in sub-Saharan Africa (SSA). Soil GHG emissions from African natural terrestrial systems ranged from 3.3 to 57.0 Mg carbon dioxide (CO2) ha−1 yr−1, −4.8 to 3.5 kg methane (CH4) ha−1 yr−1 and −0.1 to 13.7 kg nitrous oxide (N2O) ha−1 yr−1. Soil physical and chemical properties, rewetting, vegetation type, forest management and land-use changes were all found to be important factors affecting soil GHG emissions. Greenhouse gas emissions from African aquatic systems ranged from 5.7 to 232.0 Mg CO2 ha−1 yr−1, −26.3 to 2741.9 kg CH4 ha−1 yr−1 and 0.2 to 3.5 kg N2O ha−1 yr−1 and were strongly affected by discharge. Soil GHG emissions from African croplands ranged from 1.7 to 141.2 Mg CO2 ha−1 yr−1, −1.3 to 66.7 kg CH4 ha−1 yr−1and 0.05 to 112.0 kg N2O ha−1 yr−1 and the N2O emission factor (EF) ranged from 0.01 to 4.1 %. Incorporation of crop residues or manure with inorganic fertilizers resulted in significant changes in GHG emissions but these were different for CO2 and N2O. Soil GHG emissions in vegetable gardens ranged from 73.3 to 132.0 Mg CO2 ha−1 yr−1 and 53.4 to 177.6 kg N2O ha−1 yr−1 and N2O EFs ranged from 3 to 4 %. Soil CO2 and N2O emissions from agroforestry were 38.6 Mg CO2 ha−1 yr−1 and 0.2 to 26.7 kg N2O ha−1 yr−1, respectively. Improving fallow with nitrogen (N)-fixing trees increased CO2 and N2O emissions compared to conventional croplands and type and quality of plant residue is likely to be an important control factor affecting N2O emissions. Throughout agricultural lands, N2O emissions slowly increased with N inputs below 150 kg N ha−1 yr−1 and increased exponentially with N application rates up to 300 kg N ha−1 yr−1. The lowest yield-scaled N2O emissions were reported with N application rates ranging between 100 and 150 kg N ha−1. Overall, total CO2 equivalent (eq) emissions from African natural and agricultural lands were 56.9 ± 12.7 Pg CO2 eq yr−1 and natural and agricultural lands contributed 76.3 and 23.7 %, respectively. Additional GHG emission measurements throughout Africa agricultural and natural lands are urgently required to reduce uncertainty on annual GHG emissions from the different land uses and identify major control factors and mitigation options on emissions. There is also a need to develop a common strategy for addressing this data gap that may involve identifying priorities for data acquisition, utilizing appropriate technologies, and establishing networks and collaboration.

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Greenhouse Gas Emissions from Soil Cultivated with Vegetables in Crop Rotation under Integrated, Organic and Organic Conservation Management in a Mediterranean Environment

Agronomy ◽

10.3390/agronomy9080446 ◽

2019 ◽

Vol 9 (8) ◽

pp. 446 ◽

Cited By ~ 6

Author(s):

Simona Bosco ◽

Iride Volpi ◽

Daniele Antichi ◽

Giorgio Ragaglini ◽

Christian Frasconi

Keyword(s):

Greenhouse Gas ◽

Co2 Emissions ◽

Crop Rotation ◽

Plant Biomass ◽

Cropping Systems ◽

Ghg Emissions ◽

Agricultural Practices ◽

N2o Emissions ◽

Mediterranean Environment ◽

Foeniculum Vulgare

A combination of organic and conservation approaches have not been widely tested, neither considering agronomic implications nor the impacts on the environment. Focussing on the effect of agricultural practices on greenhouse gas (GHG) emissions from soil, the hypothesis of this research is that the organic conservation system (ORG+) may reduce emissions of N2O, CH4 and CO2 from soil, compared to an integrated farming system (INT) and an organic (ORG) system in a two-year irrigated vegetable crop rotation set up in 2014, in a Mediterranean environment. The crop rotation included: Savoy cabbage (Brassica oleracea var. sabauda L. cv. Famosa), spring lettuce (Lactuca sativa L. cv. Justine), fennel (Foeniculum vulgare Mill. cv. Montebianco) and summer lettuce (L. sativa cv. Ballerina). Fluxes from soil of N2O, CH4 and CO2 were measured from October 2014 to July 2016 with the flow-through non-steady state chamber technique using a mobile instrument equipped with high precision analysers. Both cumulative and daily N2O emissions were mainly lower in ORG+ than in INT and ORG. All the cropping systems acted as a sink of CH4, with no significant differences among treatments. The ORG and ORG+ systems accounted for higher cumulative and daily CO2 emissions than INT, maybe due to the stimulating effect on soil respiration of organic material (fertilizers/plant biomass) supplied in ORG and ORG+. Overall, the integration of conservation and organic agriculture showed a tendency for higher CO2 emissions and lower N2O emissions than the other treatments, without any clear results on its potential for mitigating GHG emissions from soil.

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A comprehensive dataset for global, regional and national greenhouse gas emissions by sector 1970–2019

10.5194/essd-2021-228 ◽

2021 ◽

Author(s):

Jan C. Minx ◽

William F. Lamb ◽

Robbie M. Andrew ◽

Josep G. Canadell ◽

Monica Crippa ◽

...

Keyword(s):

Land Use ◽

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Co2 Emissions ◽

Ghg Emissions ◽

N2o Emissions ◽

Ghg Emission ◽

High Confidence ◽

Gas Emissions ◽

Emission Growth

Abstract. To track progress towards keeping warming well below 2 °C, as agreed upon in the Paris Agreement, comprehensive and reliable information on anthropogenic sources of greenhouse gas emissions (GHG) is required. Here we provide a dataset on anthropogenic GHG emissions 1970–2019 with a broad country and sector coverage. We build the dataset from recent releases of the “Emissions Database for Global Atmospheric Research” (EDGAR) for CO2 emissions from fossil fuel combustion and industry (FFI), CH4 emissions, N2O emissions, and fluorinated gases, and use a well-established fast-track method to extend this dataset from 2018 to 2019. We complement this with data on net CO2 emissions from land use, land-use change and forestry (LULUCF) from three bookkeeping models. We provide an assessment of the uncertainties in each greenhouse gas at the 90 % confidence interval (5th–95th percentile) by combining statistical analysis and comparisons of global emissions inventories with an expert judgement informed by the relevant scientific literature. We identify important data gaps: CH4 and N2O emissions could be respectively 10–20 % higher than reported in EDGAR once all emissions are accounted. F-gas emissions estimates for individual species in EDGARv5 do not align well with atmospheric measurements and the F-gas total exceeds measured concentrations by about 30 %. However, EDGAR and official national emission reports under the UNFCCC do not comprehensively cover all relevant F-gas species. Excluded F-gas species such as chlorofluorocarbons (CFCs) or hydrochlorofluorocarbons (HCFCs) are larger than the sum of the reported species. GHG emissions in 2019 amounted to 59 ± 6.6 GtCO2eq: CO2 emissions from FFI were 38 ± 3.0 Gt, CO2 from LULUCF 6.6 ± 4.6 Gt, CH4 11 ± 3.3 GtCO2eq, N2O 2.4 ±1.5 GtCO2eq and F-gases 1.6 ± 0.49 GtCO2eq. Our analysis of global, anthropogenic GHG emission trends over the past five decades (1970–2019) highlights a pattern of varied, but sustained emissions growth. There is high confidence that global anthropogenic greenhouse gas emissions have increased every decade. Emission growth has been persistent across different (groups of) gases. While CO2 has accounted for almost 75 % of the emission growth since 1970 in terms of CO2eq as reported here, the combined F-gases have grown at a faster rate than other GHGs, albeit starting from low levels in 1970. Today, F-gases make a non-negligible contribution to global warming – even though CFCs and HCFCs, regulated under the Montreal Protocol and not included in our estimates, have contributed more. There is further high confidence that global anthropogenic GHG emission levels were higher in 2010-2019 than in any previous decade and GHG emission levels have grown across the most recent decade. While average annual greenhouse gas emissions growth slowed between 2010–2019 compared to 2000–2009, the absolute increase in average decadal GHG emissions from the 2000s to the 2010s has been the largest since the 1970s – and within all human history as suggested by available long-term data. We note considerably higher rates of change in GHG emissions between 2018 and 2019 than for the entire decade 2010–2019, which is numerically comparable with the period of high GHG emissions growth during the 2000s, but we place low confidence in this finding as the majority of the growth is driven by highly uncertain increases in CO2-LULUCF emissions as well as the use of preliminary data and extrapolation methodologies for these most recent years. While there is a growing number of countries today on a sustained emission reduction trajectory, our analysis further reveals that there are no global sectors that show sustained reductions in GHG emissions. We conclude by highlighting that tracking progress in climate policy requires substantial investments in independent GHG emission accounting and monitoring as well as the available 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.5053056.

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