Greenhouse gas emissions from laboratory-scale fires in wildland fuels depend on fire spread mode and phase of combustion

Abstract. Experimental fires were conducted in a combustion wind tunnel facility to explore the role of fire spread mode on the resulting emissions profile from combustion of fine (< 6 mm) Eucalyptus litter fuels. Fires were burnt spreading with the wind (heading fire), perpendicular to the wind (flanking fire) and against the wind (backing fire). Greenhouse gas compounds (i.e. CO2, CH4 and N2O) and CO were quantified using off-axis integrated-cavity-output spectroscopy (off-axis ICOS). A dilution system was employed with the off-axis ICOS technique to prevent spectral broadening of the CO emissions peak and to enable simultaneous quantification of N2O and CO. The forward rate of spread was 20 times faster and the Byram fireline intensity was 20 times higher for heading fires compared to flanking and backing fires. Emissions factors calculated using a carbon mass balance technique (along with statistical testing) showed that most of the carbon was emitted as CO2, with heading fires emitting 17% more CO2 than flanking and 9.5% more CO2 than backing fires, and about twice as much CO. Heading fires had less than half as much carbon remaining in combustion residues. Statistically significant differences in CH4 and N2O emissions factors were not found with respect to fire spread mode. Emissions factors calculated per unit of dry fuel consumed showed that combustion phase (i.e. flaming or smouldering) had a statistically significant impact, with CO and N2O emissions increasing during smouldering combustion and CO2 emissions factors decreasing. Findings on the equivalence of different emissions factor reporting methods are discussed along with the impact of our results for emissions accounting. The primary implication of this study is that prescribed fire practices might be modified to mitigate greenhouse gas emissions from forested landscapes by the preferential application of flanking and backing fires over heading fires. Future research could involve wind tunnel testing with more realistic fuel architectures and could also quantify particulate emissions with different fire spread modes.

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Greenhouse gas emissions from laboratory-scale fires in wildland fuels depend on fire spread mode and phase of combustion

Atmospheric Chemistry and Physics ◽

10.5194/acp-15-5259-2015 ◽

2015 ◽

Vol 15 (9) ◽

pp. 5259-5273 ◽

Cited By ~ 19

Author(s):

N. C. Surawski ◽

A. L. Sullivan ◽

C. P. Meyer ◽

S. H. Roxburgh ◽

P. J. Polglase

Keyword(s):

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Fire Spread ◽

Statistical Testing ◽

N2o Emissions ◽

Gas Emissions ◽

Combustion Phase ◽

Carbon Mass Balance ◽

Ch4 And N2o ◽

The Impact

Abstract. Free-burning experimental fires were conducted in a wind tunnel to explore the role of ignition type and thus fire spread mode on the resulting emissions profile from combustion of fine (< 6 mm in diameter) Eucalyptus litter fuels. Fires were burnt spreading with the wind (heading fire), perpendicular to the wind (flanking fire) and against the wind (backing fire). Greenhouse gas compounds (i.e. CO2, CH4 and N2O) and CO were quantified using off-axis integrated-cavity-output spectroscopy. Emissions factors calculated using a carbon mass balance technique (along with statistical testing) showed that most of the carbon was emitted as CO2, with heading fires emitting 17% more CO2 than flanking and 9.5% more CO2 than backing fires, and about twice as much CO as flanking and backing fires. Heading fires had less than half as much carbon remaining in combustion residues. Statistically significant differences in CH4 and N2O emissions factors were not found with respect to fire spread mode. Emissions factors calculated per unit of dry fuel consumed showed that combustion phase (i.e. flaming or smouldering) had a statistically significant impact, with CO and N2O emissions increasing during smouldering combustion and CO2 emissions decreasing. Findings on the equivalence of different emissions factor reporting methods are discussed along with the impact of our results for emissions accounting and potential sampling biases associated with our work. The primary implication of this study is that prescribed fire practices could be modified to mitigate greenhouse gas emissions from forests by judicial use of ignition methods to induce flanking and backing fires over heading fires.

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Effect of Biochar on Soil Greenhouse Gas Emissions at the Laboratory and Field Scales

Soil Systems ◽

10.3390/soilsystems3010008 ◽

2019 ◽

Vol 3 (1) ◽

pp. 8 ◽

Cited By ~ 23

Author(s):

Rivka Fidel ◽

David Laird ◽

Timothy Parkin

Keyword(s):

Field Study ◽

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Cropping Systems ◽

Cropping System ◽

N2o Emission ◽

N2o Emissions ◽

Gas Emissions ◽

Continuous Corn ◽

The Impact

Biochar application to soil has been proposed as a means for reducing soil greenhouse gas emissions and mitigating climate change. The effects, however, of interactions between biochar, moisture and temperature on soil CO2 and N2O emissions, remain poorly understood. Furthermore, the applicability of lab-scale observations to field conditions in diverse agroecosystems remains uncertain. Here we investigate the impact of a mixed wood gasification biochar on CO2 and N2O emissions from loess-derived soils using: (1) controlled laboratory incubations at three moisture (27, 31 and 35%) and three temperature (10, 20 and 30 °C) levels and (2) a field study with four cropping systems (continuous corn, switchgrass, low diversity grass mix and high diversity grass-forb mix). Biochar reduced N2O emissions under specific temperatures and moistures in the laboratory and in the continuous corn cropping system in the field. However, the effect of biochar on N2O emissions was only significant in the field and no effect on cumulative CO2 emissions was observed. Cropping system also had a significant effect in the field study, with soils in grass and grass-forb cropping systems emitting more CO2 and less N2O than corn cropping systems. Observed biochar effects were consistent with previous studies showing that biochar amendments can reduce soil N2O emissions under specific but not all, conditions. The disparity in N2O emission responses at the lab and field scales suggests that laboratory incubation experiments may not reliably predict the impact of biochar at the field scale.

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Effect of Biochar on Soil Greenhouse Gas Emissions at the Laboratory and Field Scales

10.20944/preprints201810.0315.v1 ◽

2018 ◽

Author(s):

Rivka B. Fidel ◽

David A. Laird ◽

Timothy B. Parkin

Keyword(s):

Field Study ◽

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Cropping Systems ◽

Cropping System ◽

N2o Emission ◽

N2o Emissions ◽

Gas Emissions ◽

Continuous Corn ◽

The Impact

Biochar application to soil has been proposed as a means for reducing soil greenhouse gas emissions and mitigating climate change. The effects, however, of interactions between biochar, moisture and temperature on soil CO2 and N2O emissions, remain poorly understood.  Furthermore, the applicability of lab-scale observations to field conditions in diverse agroecosystems remains uncertain. Here we investigate the impact of a mixed wood gasification biochar on CO2 and N2O emissions from loess-derived soils using: (1) controlled laboratory incubations at three moisture (27, 31 and 35%) and three temperature (10, 20 and 30°C) levels, and (2) a field study with four cropping systems (continuous corn, switchgrass, low diversity grass mix, and high diversity grass-forb mix). Biochar reduced N2O emissions under specific temperatures and moistures in the laboratory and in the continuous corn cropping system in the field. However, the effect of biochar on N2O emissions was only significant in the field, and no effect on cumulative CO2 emissions was observed. Cropping system also had a significant effect in the field study, with soils in grass and grass-forb cropping systems emitting more CO2 and less N2O than corn cropping systems. Observed biochar effects were consistent with previous studies showing that biochar amendments can reduce soil N2O emissions under specific, but not all, conditions. The disparity in N2O emission responses at the lab and field scales suggests that laboratory incubation experiments are not reliable for predicting the impact of biochar at the field scale.

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Estimation of greenhouse gas emissions in the agro-industrial system of sugarcane in Piauí, Brazil

Ciência e Natura ◽

10.5902/2179460x36777 ◽

2019 ◽

Vol 41 ◽

pp. e50

Author(s):

Lilian De Castro Moraes Pinto

Keyword(s):

Production Process ◽

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Field Research ◽

Physical Structure ◽

Carbon Equivalent ◽

N2o Emissions ◽

Gas Emissions ◽

Human Labor ◽

Ch4 And N2o

The present study presents an estimate of greenhouse gas emissions throughout the production process of ethanol and sugar originated from sugarcane in Piauí. The field research was carried out in a mill with an attached distillery, where the harvest was conducted manually, from January to December 2015. Life Cycle Assessment principles were considered in the quantification of total CO2, CH4 and N2O emissions in the stages of agriculture, industrialization and distribution, converting them according to their global-warming potential into carbon-equivalent (CO2eq). The use of fuels, agriculture inputs, sugarcane burning, manufacture of machinery and physical structure of the mill, application of pesticides, seeds, use of chemical reagents in the production process and human labor were considered in this study. The results show a total emission of 2,413.3 kg CO2eq /ha.year, and the main key sources were sugarcane burning (48%) and use of chemical products (29.6 %). The industrial and distribution stages contributed with 2% of the emissions each. There was an emission of 29.9 kg CO2eq per ton of sugarcane processed and it was estimated that there would be a net reduction of 83% of emissions if the harvesting could be thoroughly conducted mechanically.

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Seeing Double: Peace, Order, and Good Government, and the Impact of Federal Greenhouse Gas Emissions Legislation on Provincial Jurisdiction

SSRN Electronic Journal ◽

10.2139/ssrn.3522915 ◽

2020 ◽

Author(s):

Andrew Leach ◽

Eric M. Adams

Keyword(s):

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Gas Emissions ◽

Good Government ◽

The Impact

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HOW GREEN IS YOUR FOOTPRINT? THE IMPACT OF GREENHOUSE GAS EMISSIONS ON STRATEGIC PLANNING

Proceedings of the Water Environment Federation ◽

10.2175/193864708790894485 ◽

2008 ◽

Vol 2008 (6) ◽

pp. 783-792 ◽

Cited By ~ 2

Author(s):

Patricia Scanlan ◽

Holly Elmendorf ◽

Hari Santha ◽

James Rowan

Keyword(s):

Strategic Planning ◽

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Gas Emissions ◽

Green Is ◽

The Impact

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Observational Constraints on Past Attributable Warming and Predictions of Future Global Warming

Journal of Climate ◽

10.1175/jcli3802.1 ◽

2006 ◽

Vol 19 (13) ◽

pp. 3055-3069 ◽

Cited By ~ 129

Author(s):

Peter A. Stott ◽

John F. B. Mitchell ◽

Myles R. Allen ◽

Thomas L. Delworth ◽

Jonathan M. Gregory ◽

...

Keyword(s):

Twentieth Century ◽

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Temperature Change ◽

Greenhouse Warming ◽

Gas Emissions ◽

Aerosol Forcing ◽

Future Global Warming ◽

Cooling Effects ◽

The Impact

Abstract This paper investigates the impact of aerosol forcing uncertainty on the robustness of estimates of the twentieth-century warming attributable to anthropogenic greenhouse gas emissions. Attribution analyses on three coupled climate models with very different sensitivities and aerosol forcing are carried out. The Third Hadley Centre Coupled Ocean–Atmosphere GCM (HadCM3), Parallel Climate Model (PCM), and GFDL R30 models all provide good simulations of twentieth-century global mean temperature changes when they include both anthropogenic and natural forcings. Such good agreement could result from a fortuitous cancellation of errors, for example, by balancing too much (or too little) greenhouse warming by too much (or too little) aerosol cooling. Despite a very large uncertainty for estimates of the possible range of sulfate aerosol forcing obtained from measurement campaigns, results show that the spatial and temporal nature of observed twentieth-century temperature change constrains the component of past warming attributable to anthropogenic greenhouse gases to be significantly greater (at the 5% level) than the observed warming over the twentieth century. The cooling effects of aerosols are detected in all three models. Both spatial and temporal aspects of observed temperature change are responsible for constraining the relative roles of greenhouse warming and sulfate cooling over the twentieth century. This is because there are distinctive temporal structures in differential warming rates between the hemispheres, between land and ocean, and between mid- and low latitudes. As a result, consistent estimates of warming attributable to greenhouse gas emissions are obtained from all three models, and predictions are relatively robust to the use of more or less sensitive models. The transient climate response following a 1% yr−1 increase in CO2 is estimated to lie between 2.2 and 4 K century−1 (5–95 percentiles).

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