scholarly journals Emissions of trace gases from Australian temperate forest fires: emission factors and dependence on modified combustion efficiency

2017 ◽  
Author(s):  
Elise-Andrée Guérette ◽  
Clare Paton-Walsh ◽  
Maximilien Desservettaz ◽  
Thomas E. L. Smith ◽  
Liubov Volkova ◽  
...  
Keyword(s):  
Forest Fires ◽  
Temperate Forest ◽  
Combustion Efficiency ◽  
Emission Factors ◽  
Trace Gas ◽  
Airborne Measurements ◽  
Trace Gas Emissions ◽  
Open Path ◽  
Modified Combustion Efficiency

Abstract. We characterised trace gas emissions from Australian temperate forest fires through a mixture of in situ open-path FTIR measurements spectroscopy and selective ion flow tube mass spectrometry (SIFT-MS) and White cell FTIR spectroscopy of grab samples. We report emission factors for a total of 25 trace gas species measured in smoke from nine prescribed fires. We find significant dependence on modified combustion efficiency (MCE) for some species, although regional differences indicate that the use of MCE as a proxy may be limited. We also find that the fire-integrated MCE values derived from our in situ on-the-ground open-path measurements are not significantly different from those reported for airborne measurements of smoke from fires in the same ecosystem. We then compare our average emission factors to those measured for fires in North American temperate ecosystems and for fires in Australian savanna and find that, although emission factors of some species agree within 20 %, others differ by a factor of 2 or more. This indicates that the use of ecosystem-specific emission factors is warranted for applications involving emissions from Australian forest fires.

scholarly journals Emissions of trace gases from Australian temperate forest fires: emission factors and dependence on modified combustion efficiency

2018 ◽  
Vol 18 (5) ◽  
pp. 3717-3735 ◽  
Author(s):  
Elise-Andrée Guérette ◽  
Clare Paton-Walsh ◽  
Maximilien Desservettaz ◽  
Thomas E. L. Smith ◽  
Liubov Volkova ◽  
...  
Keyword(s):  
Forest Fires ◽  
Temperate Forest ◽  
Combustion Efficiency ◽  
Emission Factors ◽  
Trace Gas ◽  
Ion Flow ◽  
Airborne Measurements ◽  
Trace Gas Emissions ◽  
Open Path ◽  
Modified Combustion Efficiency

Abstract. We characterised trace gas emissions from Australian temperate forest fires through a mixture of open-path Fourier transform infrared (OP-FTIR) measurements and selective ion flow tube mass spectrometry (SIFT-MS) and White cell FTIR analysis of grab samples. We report emission factors for a total of 25 trace gas species measured in smoke from nine prescribed fires. We find significant dependence on modified combustion efficiency (MCE) for some species, although regional differences indicate that the use of MCE as a proxy may be limited. We also find that the fire-integrated MCE values derived from our in situ on-the-ground open-path measurements are not significantly different from those reported for airborne measurements of smoke from fires in the same ecosystem. We then compare our average emission factors to those measured for temperate forest fires elsewhere (North America) and for fires in another dominant Australian ecosystem (savanna) and find significant differences in both cases. Indeed, we find that although the emission factors of some species agree within 20 %, including those of hydrogen cyanide, ethene, methanol, formaldehyde and 1,3-butadiene, others, such as acetic acid, ethanol, monoterpenes, ammonia, acetonitrile and pyrrole, differ by a factor of 2 or more. This indicates that the use of ecosystem-specific emission factors is warranted for applications involving emissions from Australian forest fires.

scholarly journals Airborne measurements of fire Emission Factors for African biomass burning sampled during the MOYA Campaign

2020 ◽  
Author(s):  
Patrick A. Barker ◽  
Grant Allen ◽  
Thomas Bannan ◽  
Archit Mehra ◽  
Keith N. Bower ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Combustion Efficiency ◽  
Emission Factors ◽  
Airborne Measurements ◽  
Atlantic Seaboard ◽  
Trace Gas Emissions ◽  
Fire Plumes ◽  
Carbon Dioxide Co2 ◽  
Continental Outflow ◽  
Modified Combustion Efficiency

Abstract. Airborne sampling of methane (CH4), carbon dioxide (CO2), carbon monoxide (CO), and nitrous oxide (N2O) mole fractions was conducted during field campaigns targeting fires over Senegal in February and March 2017, and Uganda in January 2019. The majority of fire plumes sampled were close to, or directly over burning vegetation, with the exception of two longer-range flights over the West African Atlantic seaboard, (100–300 km from source) where the continental outflow of biomass burning emissions from a wider area of West Africa was sampled. Fire Emission Factors (EFs) and modified combustion efficiencies (MCEs) were estimated from the enhancements in measured mole fractions. For the Senegalese fires, mean EFs and corresponding one-standard deviation variabilities, in units of g per kg of dry fuel were 1.8 (± 0.06) for CH4, 1633 (± 56.4) for CO2 and 679 (± 1.6) for CO, with a mean MCE of 0.94 (± 0.005). For the Ugandan fires, mean EFs (in units of g kg−1) were 3.1 (± 0.1) for CH4, 1610 (± 54.9) for CO2 and 78 (± 1.9) for CO, with a mean modified combustion efficiency of 0.93 (± 0.004). A mean N2O EF of 0.08 (± 0.002) g kg−1 is also reported for one flight over Uganda; issues with temperature control of the instrument optical bench prevented N2O EFs from being obtained for other flights over Uganda. This study has provided new datasets of African biomass burning EFs and MCEs for two distinct study regions, in which both have been studied little by aircraft measurement previously. These results highlight the important intracontinental variability of biomass burning trace gas emissions, and can be used to better constrain future biomass burning emission budgets. More generally, these results highlight the importance of regional and fuel-type variability when attempting to spatially scale biomass burning emissions. Further work to constrain EFs at more local scales and for more specific (and quantifiable) fuel types will serve to improve global estimates of biomass burning emissions of climate-relevant gases.

scholarly journals Airborne measurements of fire emission factors for African biomass burning sampled during the MOYA campaign

2020 ◽  
Vol 20 (23) ◽  
pp. 15443-15459 ◽  
Author(s):  
Patrick A. Barker ◽  
Grant Allen ◽  
Martin Gallagher ◽  
Joseph R. Pitt ◽  
Rebecca E. Fisher ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Combustion Efficiency ◽  
Emission Factors ◽  
Airborne Measurements ◽  
Atlantic Seaboard ◽  
Trace Gas Emissions ◽  
Fire Plumes ◽  
Carbon Dioxide Co2 ◽  
Continental Outflow ◽  
Modified Combustion Efficiency

Abstract. Airborne sampling of methane (CH4), carbon dioxide (CO2), carbon monoxide (CO), and nitrous oxide (N2O) mole fractions was conducted during field campaigns targeting fires over Senegal in February and March 2017 and Uganda in January 2019. The majority of fire plumes sampled were close to or directly over burning vegetation, with the exception of two longer-range flights over the West African Atlantic seaboard (100–300 km from source), where the continental outflow of biomass burning emissions from a wider area of West Africa was sampled. Fire emission factors (EFs) and modified combustion efficiencies (MCEs) were estimated from the enhancements in measured mole fractions. For the Senegalese fires, mean EFs and corresponding uncertainties in units of gram per kilogram of dry fuel were 1.8±0.19 for CH4, 1633±171.4 for CO2, and 67±7.4 for CO, with a mean MCE of 0.94±0.005. For the Ugandan fires, mean EFs were 3.1±0.35 for CH4, 1610±169.7 for CO2, and 78±8.9 for CO, with a mean modified combustion efficiency of 0.93±0.004. A mean N2O EF of 0.08±0.002 g kg−1 is also reported for one flight over Uganda; issues with temperature control of the instrument optical bench prevented N2O EFs from being obtained for other flights over Uganda. This study has provided new datasets of African biomass burning EFs and MCEs for two distinct study regions, in which both have been studied little by aircraft measurement previously. These results highlight the important intracontinental variability of biomass burning trace gas emissions and can be used to better constrain future biomass burning emission budgets. More generally, these results highlight the importance of regional and fuel-type variability when attempting to spatially scale biomass burning emissions. Further work to constrain EFs at more local scales and for more specific (and quantifiable) fuel types will serve to improve global estimates of biomass burning emissions of climate-relevant gases.

Airborne measurements of trace gas emissions from African biomass burning during the MOYA Campaign

2020 ◽  
Author(s):  
Patrick Barker ◽  
Grant Allen ◽  
Thomas Bannan ◽  
Joseph Pitt ◽  
Stephane Bauguitte ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Carbon Emissions ◽  
Linear Trend ◽  
Emission Factors ◽  
Climate Feedback ◽  
Trace Gas ◽  
Atmospheric Measurements ◽  
African Region ◽  
Airborne Measurements

<p>Biomass burning (BB) is known to contribute significantly to the global budgets of atmospheric trace gases and aerosols.  Approximately 1.6–4.1 Pg of CO<sub>2</sub>, 11–53 Tg CH<sub>4</sub> and 0.1–0.3 Tg of N<sub>2</sub>O is emitted to the atmosphere per year as a result of biomass burning on a global scale (Crutzen and Andreae, 2016). The contribution of BB to global GHG budgets is likely to increase over time due to climate feedback of warming and more widespread drought conditions increasing the likelihood and spread of wildfire events (Liu et al., 2014).</p><p>It is estimated that Africa accounts for approximately 52% of all BB carbon emissions, with the Northern Sub-Saharan African region alone accounting for 20-25% of global BB carbon emissions (van der Werf et al. 2010; Ichoku et al. 2016). Many of these fires are anthropogenic in origin, and occur for reasons such as clearing land for agricultural use, management of natural savannah vegetation, or as pest control (Andreae, 1991).  Despite the African contribution to global BB emissions, there are limited in situ studies of African wildfire emissions.</p><p>In situ measurements of CH<sub>4</sub>, CO<sub>2</sub> and N<sub>2</sub>O and CO in biomass burning plumes were carried out in Senegal in February 2017 and in Uganda in January 2019 during the Methane Observations and Yearly Assessments (MOYA) project. These observations were carried out using the Facility for Airborne Atmospheric Measurements BAe-146 Atmospheric Research Aircraft (ARA), which is fitted with a range of specialist instrumentation for in situ trace gas sampling. Emission factors for these species were calculated for both near-field and far-field biomass burning plumes. A notable difference in the linear trend between methane emission factors and completeness-of-combustion was identified between Senegalese and Ugandan fires.</p>

scholarly journals Precise multispecies agricultural gas flux determined using broadband open-path dual-comb spectroscopy

2021 ◽  
Vol 7 (14) ◽  
pp. eabe9765
Author(s):  
Daniel I. Herman ◽  
Chinthaka Weerasekara ◽  
Lindsay C. Hutcherson ◽  
Fabrizio R. Giorgetta ◽  
Kevin C. Cossel ◽  
...  
Keyword(s):  
Ecological Monitoring ◽  
Trace Gas ◽  
Gas Analyzer ◽  
Gas Flux ◽  
Time Resolved ◽  
Trace Gas Emissions ◽  
Open Path ◽  
Statistical Precision ◽  
Methane Fluxes ◽  
Flux Quantification

Advances in spectroscopy have the potential to improve our understanding of agricultural processes and associated trace gas emissions. We implement field-deployed, open-path dual-comb spectroscopy (DCS) for precise multispecies emissions estimation from livestock. With broad atmospheric dual-comb spectra, we interrogate upwind and downwind paths from pens containing approximately 300 head of cattle, providing time-resolved concentration enhancements and fluxes of CH4, NH3, CO2, and H2O. The methane fluxes determined from DCS data and fluxes obtained with a colocated closed-path cavity ring-down spectroscopy gas analyzer agree to within 6%. The NH3 concentration retrievals have sensitivity of 10 parts per billion and yield corresponding NH3 fluxes with a statistical precision of 8% and low systematic uncertainty. Open-path DCS offers accurate multispecies agricultural gas flux quantification without external calibration and is easily extended to larger agricultural systems where point-sampling-based approaches are insufficient, presenting opportunities for field-scale biogeochemical studies and ecological monitoring.

Trace gas emissions from chaparral and boreal forest fires

1989 ◽  
Vol 94 (D2) ◽  
pp. 2255 ◽  
Author(s):  
Wesley R. Cofer ◽  
Joel S. Levine ◽  
Daniel I. Sebacher ◽  
Edward L. Winstead ◽  
Philip J. Riggan ◽  
...  
Keyword(s):  
Boreal Forest ◽  
Forest Fires ◽  
Trace Gas ◽  
Gas Emissions ◽  
Trace Gas Emissions

scholarly journals Biomass burning combustion efficiency observed from space using measurements of CO and NO<sub>2</sub> by the TROPOspheric Monitoring Instrument (TROPOMI)

2021 ◽  
Vol 21 (2) ◽  
pp. 597-616
Author(s):  
Ivar R. van der Velde ◽  
Guido R. van der Werf ◽  
Sander Houweling ◽  
Henk J. Eskes ◽  
J. Pepijn Veefkind ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Biomass Burning ◽  
Forest Fires ◽  
Combustion Efficiency ◽  
Spatiotemporal Variability ◽  
Emission Inventories ◽  
Airborne Measurements ◽  
Monitoring Instrument ◽  
Smoldering Combustion ◽  
The World

Abstract. The global fire emission inventories depend on ground and airborne measurements of species-specific emission factors (EFs), which translate dry matter losses due to fires to actual trace gas and aerosol emissions. The EFs of nitrogen oxides (NOx) and carbon monoxide (CO) can function as a proxy for combustion efficiency to distinguish flaming from smoldering combustion. The uncertainties in these EFs remain large as they are limited by the spatial and temporal representativeness of the measurements. The global coverage of satellite observations has the advantage of filling this gap, making these measurements highly complementary to ground-based or airborne data. We present a new analysis of biomass burning pollutants using space-borne data to investigate the spatiotemporal efficiency of fire combustion. Column measurements of nitrogen dioxide and carbon monoxide (XNO2 and XCO) from the TROPOspheric Monitoring Instrument (TROPOMI) are used to quantify the relative atmospheric enhancements of these species over different fire-prone regions around the world. We find spatial and temporal patterns in the ΔXNO2 ∕ ΔXCO ratio that point to distinct differences in biomass burning behavior. Such differences are induced by the burning phase of the fire (e.g., high-temperature flaming vs. low-temperature smoldering combustion) and burning practice (e.g., the combustion of logs, coarse woody debris and soil organic matter vs. the combustion of fine fuels such as savanna grasses). The sampling techniques and the signal-to-noise ratio of the retrieved ΔXNO2 ∕ ΔXCO signals were quantified with WRF-Chem experiments and showed similar distinct differences in combustion types. The TROPOMI measurements show that the fraction of surface smoldering combustion is much larger for the boreal forest fires in the upper Northern Hemisphere and peatland fires in Indonesia. These types of fires cause a much larger increase (3 to 6 times) in ΔXCO relative to ΔXNO2 than elsewhere in the world. The high spatial and temporal resolution of TROPOMI also enables the detection of spatial gradients in combustion efficiency at smaller regional scales. For instance, in the Amazon, we found higher combustion efficiency (up to 3-fold) for savanna fires than for the nearby tropical deforestation fires. Out of two investigated fire emission products, the TROPOMI measurements support the broad spatial pattern of combustion efficiency rooted in GFED4s. Meanwhile, TROPOMI data also add new insights into regional variability in combustion characteristics that are not well represented in the different emission inventories, which can help the fire modeling community to improve their representation of the spatiotemporal variability in EFs.

Sign in / Sign up

Export Citation Format

Share Document