Particulate emissions from fires in central Siberian Scots pine forests

2005 ◽  
Vol 35 (9) ◽  
pp. 2207-2217 ◽  
Author(s):  
Yuri N Samsonov ◽  
Konstantin P Koutsenogii ◽  
V I Makarov ◽  
Andrey V Ivanov ◽  
Valery A Ivanov ◽  
...  
Keyword(s):  
Scots Pine ◽  
Forest Fires ◽  
Ground Surface ◽  
Particulate Emissions ◽  
Total Biomass ◽  
Carbonaceous Aerosols ◽  
Particulate Emission ◽  
Fire Emissions ◽  
Aerosol Mass ◽  
Forest Sites

Siberian boreal forest fires burn large areas annually, resulting in smoke that releases large amounts of particulate emission into the atmosphere. We sampled aerosol emissions from experimental fires on three Scots pine (Pinus sylvestris L.) forest sites of central Siberia. Emissions from ground-based aerosol samples were 0.1–0.7 t/ha. This value represented 1%–7% of the total biomass (10–30 t/ha) consumed during the experimental fires. We were able to classify the chemical composition of 77%–90% of the mass of particulate fire emissions. Chemical analysis indicated that an average of 8%–17% of the particulate composition was of mineral origin. Carbonaceous aerosols created because of incomplete combustion ranged from 50% to 70% of the total aerosol mass. The fraction of aerosols containing elemental carbon (EC) (i.e., graphite, soot, and charcoal) was 7%–15%. As our samples were taken near the ground surface, these results represent freshly emitted fire aerosols that have not yet had time to react with atmospheric moisture or to undergo postfire chemical or physical–chemical changes. In a typical year, where 12 × 106 – 14 × 106 ha burn in Russia, we estimate that 3 × 106 – 10 × 106 t of particulate matter may be emitted into the atmosphere.

scholarly journals Mexico city aerosol analysis during MILAGRO using high resolution aerosol mass spectrometry at the urban supersite (T0) – Part 2: Analysis of the biomass burning contribution and the non-fossil carbon fraction

2010 ◽  
Vol 10 (12) ◽  
pp. 5315-5341 ◽  
Author(s):  
A. C. Aiken ◽  
B. de Foy ◽  
C. Wiedinmyer ◽  
P. F. DeCarlo ◽  
I. M. Ulbrich ◽  
...  
Keyword(s):  
High Resolution ◽  
Mexico City ◽  
Biomass Burning ◽  
Forest Fires ◽  
Organic Aerosol ◽  
Total Carbon ◽  
Fire Emissions ◽  
Fossil Carbon ◽  
Aerosol Mass ◽  
The Impact

Abstract. Submicron aerosol was analyzed during the MILAGRO field campaign in March 2006 at the T0 urban supersite in Mexico City with a High-Resolution Aerosol Mass Spectrometer (AMS) and complementary instrumentation. Positive Matrix Factorization (PMF) of high resolution AMS spectra identified a biomass burning organic aerosol (BBOA) component, which includes several large plumes that appear to be from forest fires within the region. Here, we show that the AMS BBOA concentration at T0 correlates with fire counts in the vicinity of Mexico City and that most of the BBOA variability is captured when the FLEXPART model is used for the dispersion of fire emissions as estimated from satellite fire counts. The resulting FLEXPART fire impact factor (FIF) correlates well with the observed BBOA, acetonitrile (CH3CN), levoglucosan, and potassium, indicating that wildfires in the region surrounding Mexico City are the dominant source of BBOA at T0 during MILAGRO. The impact of distant BB sources such as the Yucatan is small during this period. All fire tracers are correlated, with BBOA and levoglucosan showing little background, acetonitrile having a well-known tropospheric background of ~100–150 pptv, and PM2.5 potassium having a background of ~160 ng m−3 (two-thirds of its average concentration), which does not appear to be related to BB sources. We define two high fire periods based on satellite fire counts and FLEXPART-predicted FIFs. We then compare these periods with a low fire period when the impact of regional fires is about a factor of 5 smaller. Fire tracers are very elevated in the high fire periods whereas tracers of urban pollution do not change between these periods. Dust is also elevated during the high BB period but this appears to be coincidental due to the drier conditions and not driven by direct dust emission from the fires. The AMS oxygenated organic aerosol (OA) factor (OOA, mostly secondary OA or SOA) does not show an increase during the fire periods or a correlation with fire counts, FLEXPART-predicted FIFs or fire tracers, indicating that it is dominated by urban and/or regional sources and not by the fires near the MCMA. A new 14C aerosol dataset is presented. Both this new and a previously published dataset of 14C analysis suggest a similar BBOA contribution as the AMS and chemical mass balance (CMB), resulting in 13% higher non-fossil carbon during the high vs. low regional fire periods. The new dataset has ~15% more fossil carbon on average than the previously published one, and possible reasons for this discrepancy are discussed. During the low regional fire period, 38% of organic carbon (OC) and 28% total carbon (TC) are from non-fossil sources, suggesting the importance of urban and regional non-fossil carbon sources other than the fires, such as food cooking and regional biogenic SOA. The ambient BBOA/ΔCH3CN ratio is much higher in the afternoon when the wildfires are most intense than during the rest of the day. Also, there are large differences in the contributions of the different OA components to the surface concentrations vs. the integrated column amounts. Both facts may explain some apparent disagreements between BB impacts estimated from afternoon aircraft flights vs. those from 24-h ground measurements. We show that by properly accounting for the non-BB sources of K, all of the BB PM estimates from MILAGRO can be reconciled. Overall, the fires from the region near the MCMA are estimated to contribute 15–23% of the OA and 7–9% of the fine PM at T0 during MILAGRO, and 2–3% of the fine PM as an annual average. The 2006 MCMA emissions inventory contains a substantially lower impact of the forest fire emissions, although a fraction of these emissions occur just outside of the MCMA inventory area.

scholarly journals Fires in ecosystems and influence on the atmosphere

2020 ◽  
Keyword(s):  
Air Quality ◽  
Air Temperature ◽  
Forest Fires ◽  
Dry Matter ◽  
Carbonaceous Aerosols ◽  
Open Burning ◽  
Fire Emissions ◽  
Air Temperature Anomaly ◽  
Maximal Average ◽  
Aerosol Index

Introduction. Fires in ecosystems, mostly after open burning, affect Ukrainian territory each year causing flora and fauna damage, soil degradation, pollutants emission, which impact air quality and human health. Fires influence the atmosphere by adding burned products and its further direct and indirect effects. Despite majority of fires are open burning, research of forest fire emissions prevail among Ukrainian scientists. Therefore, the study aimed to analyze the influence of all-type fires in Ukrainian ecosystems on substances fluxes to the atmosphere and possible changes of meteorological processes. Data and methodology. The study uses GFED4 data and inventories for analyses of forest and agricultural burned fraction, carbon and dry matter emissions for the period of 1997–2016. Additional data includes absorbed aerosol index derived from OMI (Aura) instrument and ground-based meteorological measurements. Results. Burning fraction indicates the 10 to 30% of area influencing in case of active fires. More than 90% of fires in Ukrainian ecosystems happened on the agricultural lands. The highest trends of active fires appear on the western and northern part of Ukraine, whereas burned fraction on the central territories reached up to 60% decreasing per decade. Most fires happened during two periods: March – April and July – September. The most severe fires occurred in 1999, 2001, 2005, 2007, 2008 and 2012. Average emissions in Ukraine vary from 0.2 to 1.0 g·m2·month-1 for carbon and from 0.001 to 0.003 kg·m2·month-1 for dry matter. There are three localizations of huge burning products emissions, where maximal average values reach 1.8 g·m2·month-1 for carbon and 0.005 kg·m2·month-1 for dry matter. The biggest one occurred in the Polissia forest region. Despite the maximal emission from forest fires, open burning results the biggest coverage and air quality deteriorating. Absorbing aerosol index (AAI) could be good indicator of fires in Ukrainian ecosystems and burning products emissions. Overall, AAI with values more than 0.2 correspond to dry matter emissions of 0.005–0.01 kg·m2·month-1. If AAI exceed 0.4 usual dry matter emissions exceed 0.02 kg·m2·month-1. The study finds local scale changes of air temperature and days with precipitation due to huge burning products emissions. In case of monthly average AAI exceed 1.2 during fires events, positive air temperature anomaly at the ground decrease from 0.7 to 0.1°C. The main reason is absorption of solar radiation in the atmosphere. During the next month after intensive fires in ecosystems, days with precipitation have twofold decrease: from 13-14 to 7 days with precipitation more than 0 mm, and from 2-3 to 1 day with precipitation more than 5 mm. The reason might be changes of cloudiness formation due to elevated concentrations of carbonaceous aerosols. The results obtained for atmospheric changes is planned to be verified and compared using online integrated atmospheric modelling.

scholarly journals Mexico City aerosol analysis during MILAGRO using high resolution aerosol mass spectrometry at the urban supersite (T0) – Part 2: Analysis of the biomass burning contribution and the modern carbon fraction

2009 ◽  
Vol 9 (6) ◽  
pp. 25915-25981 ◽  
Author(s):  
A. C. Aiken ◽  
B. de Foy ◽  
C. Wiedinmyer ◽  
P. F. DeCarlo ◽  
I. M. Ulbrich ◽  
...  
Keyword(s):  
High Resolution ◽  
Mexico City ◽  
Biomass Burning ◽  
Forest Fires ◽  
Carbon Sources ◽  
Average Concentration ◽  
Total Carbon ◽  
Fire Emissions ◽  
Aerosol Mass ◽  
The Impact

Abstract. Submicron aerosol was analyzed during the MILAGRO field campaign in March 2006 at the T0 urban supersite in Mexico City with a High-Resolution Aerosol Mass Spectrometer (AMS) and complementary instrumentation. Positive Matrix Factorization (PMF) of high resolution AMS spectra identified a biomass burning OA (BBOA) component, which includes several large plumes that appear to be from forest fires within the region. Here, we show that the AMS BBOA concentration at T0 correlates with fire counts in the vicinity of Mexico City and that most of the BBOA variability is captured when the FLEXPART model is used for the dispersion of fire emissions as estimated from satellite fire counts. The resulting FLEXPART fire impact index correlates well with the observed BBOA, CH3CN, levoglucosan, and potassium, indicating that wildfires in the region surrounding Mexico City are the dominant source of BBOA at T0 during MILAGRO. The impact of distant BB sources such as the Yucatan is small during this period. All fire tracers are correlated, with BBOA and levoglucosan showing little background, acetonitrile having a well-known tropospheric background of ~100–150 ppt, and PM2.5 potassium having a background of ~160 ng m−3 (two-thirds of its average concentration), which does not appear to be related to BB sources. We define two high fire periods based on satellite fire counts and predicted fire impacts. We then compare these periods with a low fire period when the impact of regional fires is about a factor of 5 smaller. Fire tracers are very elevated in the high fire periods whereas tracers of urban pollution do not change between these periods. Dust is also elevated during the high BB period but this appears to be coincidental due to the drier conditions and not driven by direct dust emission from the fires. The AMS oxygenated OA factor (OOA, mostly secondary OA or SOA) does not show an increase during the fire periods or a correlation with fire counts, FLEXPART-predicted fire impacts or fire tracers, indicating that it is dominated by urban and/or regional sources and not by the fires near the MCMA. A new 14C aerosol dataset is presented. Both this new and a previously published dataset of 14C analysis suggest a similar BBOA contribution as the AMS and chemical mass balance (CMB), resulting in 15% higher modern carbon during the high vs. low regional fire periods. The new dataset has ~15% more fossil carbon on average than the previously published one, and possible reasons for this discrepancy are discussed. During the low regional fire period, 37% of organic carbon (OC) and 30% total carbon (TC) are from modern sources, suggesting the importance of urban and regional modern carbon sources other than the fires, such as food cooking and regional biogenic SOA. Overall, the fires from the region near the MCMA are estimated to contribute 15–23% of the OA and 7–9% of the fine PM at T0 during MILAGRO, and 2–3% of the fine PM as an annual average. The 2006 MCMA emissions inventory contains a substantially lower impact of the forest fire emissions, although a fraction of these emissions occur just outside of the MCMA inventory area. The ambient BBOA/ΔCH3CN ratio is much higher in the afternoon when the wildfires are most intense than during the rest of the day, which may explain some disagreements between BB impacts from afternoon aircraft flights and those from 24-h ground measurements. Finally, we show that there are large differences in the contributions of the different OA components to the surface concentrations vs. the integrated column amounts.

The Design of Exhaust Gas Cooler for Diesel Particulate Bag Filter

2015 ◽  
Vol 737 ◽  
pp. 608-611
Author(s):  
Xiu Ye Wang ◽  
Guo Bin Li ◽  
Nan Xu
Keyword(s):  
Diesel Exhaust ◽  
Particulate Filter ◽  
Particulate Emissions ◽  
Bag Filter ◽  
Engine Exhaust ◽  
Particulate Emission ◽  
Filter System ◽  
Exhaust Temperature ◽  
Diesel Exhaust Particulate ◽  
Exhaust Particulate

Currently, the application of bag-filter technology in controlling diesel exhaust particulate emissions has been close to practical stage. As one of the key links in bag-filter technology, engine exhaust cooling can directly influence working safety of the entire exhaust particulate filter system. Thermodynamic calculations and experimental research of water-cooled chiller has provided a feasible basis for water cooler to be used in actual diesel exhaust particulate emission control system. The cooler can make engine exhaust temperature drop from 400 to 180 . Even when engine works in high-speed and high-load condition, inlet exhaust temperature of cooler can descend from 500 to 190 or so after cooling, which can still meet bag-filter system requirement of below 200 .

scholarly journals Carbonaceous aerosols contributed by traffic and solid fuel burning at a polluted rural site in Northwestern England

2011 ◽  
Vol 11 (4) ◽  
pp. 1603-1619 ◽  
Author(s):  
D. Liu ◽  
J. Allan ◽  
B. Corris ◽  
M. Flynn ◽  
E. Andrews ◽  
...  
Keyword(s):  
Solid Fuel ◽  
Mass Fraction ◽  
Organic Aerosol ◽  
Radiative Properties ◽  
Rural Site ◽  
Specific Information ◽  
Carbonaceous Aerosols ◽  
Traffic Emission ◽  
Aerosol Mass ◽  
Fuel Burning

Abstract. The experiment presented in this paper was conducted at the Holme Moss site, which is located in the southern Pennines region in Northwestern England during November–December 2006. The strong southwesterly wind during the experimental period, which enhanced the transport of urban pollutants from the conurbations of Greater Manchester and Liverpool, in addition to the seasonally increased nearby residential heating activities, made this site a receptor for pollutants from a range of sources. A factor analysis is applied to the mass spectra of organic matter (OM) measured by the Aerodyne Aerosol Mass Spectrometer (AMS) to attribute the pollutant sources. Besides the oxygenated organic aerosol (OOA), this site was found to contain a considerable fraction of primary organic aerosols (POA, mass fraction 50–70% within total mass of OM). The POA sources are attributed to be traffic emission and solid fuel burning, which are identified as hydrocarbon-like organic aerosol (HOA) and solid fuel organic aerosol (SFOA) respectively. There were strongly combined emissions of black carbon (BC) particles from both sources. The refractory BC component (rBC) was characterized by a single particle soot photometer. This site began to be influenced during the late morning by fresh traffic emissions, whereas solid fuel burning became dominant from late afternoon until night. A covariance analysis of rBC and POA was used to derive source specific emission factors of 1.61 μgHOA/μgrBC and 1.96 μgHOA/μgrBC. The absorbing properties of aerosols were characterized at multiple wavelengths (λ), and a stronger spectral dependence of absorption was observed when this site was significantly influenced by solid fuel burning. The rBC was estimated to contribute 3–16% of submicron aerosol mass. The single scattering albedo at λ = 700 nm (SSA700 nm) was significantly anti-correlated with the rBC mass fraction, but also associated with the BC mixing state. The BC incorporation/removal process therefore may play a role in modulating the radiative properties of aerosols at the site under the influence of fresh sources. Given that traffic and residential combustion of solid fuels are significant contributors of carbonaceous aerosols over Europe, these results provide important source-specific information on modeling the anthropogenic carbonaceous aerosols.

scholarly journals Impact of Blow-By Gas and Endgap Ring Position on the Variations of Particle Emissions in Gasoline Engines

Energies ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 7492
Author(s):  
Vincent Berthome ◽  
David Chalet ◽  
Jean-François Hetet
Keyword(s):  
Internal Combustion Engines ◽  
Particulate Emissions ◽  
Combustion Engines ◽  
Spark Ignition Engines ◽  
Particulate Emission ◽  
Particle Emissions ◽  
Gasoline Engines ◽  
System A ◽  
The Impact ◽  
Ring Position

Particulate emission from internal combustion engines is a complex phenomenon that needs to be understood in order to identify its main factors. To this end, it appears necessary to study the impact of unburned gases, called blow-by gases, which are reinjected into the engine intake system. A series of transient tests demonstrate their significant contribution since the particle emissions of spark-ignition engines are 1.5 times higher than those of an engine without blow-by with a standard deviation 1.5 times greater. After analysis, it is found that the decanter is not effective enough to remove completely the oil from the gases. Tests without blow-by gases also have the advantage of having a lower disparity, and therefore of being more repeatable. It appears that the position of the “endgap” formed by the first two rings has a significant impact on the amount of oil transported towards the combustion chamber by the backflow, and consequently on the variation of particle emissions. For this engine and for this transient, 57% of the particulate emissions are related to the equivalence ratio, while 31% are directly related to the ability of the decanter to remove the oil of the blowby gases and 12% of the emissions come from the backflow. The novelty of this work is to relate the particles fluctuation to the position of the endgap ring.

scholarly journals Production of peroxy nitrates in boreal biomass burning plumes over Canada during the BORTAS campaign

2016 ◽  
Vol 16 (5) ◽  
pp. 3485-3497 ◽  
Author(s):  
Marcella Busilacchio ◽  
Piero Di Carlo ◽  
Eleonora Aruffo ◽  
Fabio Biancofiore ◽  
Cesare Dari Salisburgo ◽  
...  
Keyword(s):  
Boreal Forest ◽  
Forest Fire ◽  
Biomass Burning ◽  
Forest Fires ◽  
Chemical Mechanism ◽  
Fire Emissions ◽  
Fire Plumes ◽  
Peroxy Nitrates ◽  
In Fire ◽  
The Impact

Abstract. The observations collected during the BOReal forest fires on Tropospheric oxidants over the Atlantic using Aircraft and Satellites (BORTAS) campaign in summer 2011 over Canada are analysed to study the impact of forest fire emissions on the formation of ozone (O3) and total peroxy nitrates ∑PNs, ∑ROONO2). The suite of measurements on board the BAe-146 aircraft, deployed in this campaign, allows us to calculate the production of O3 and of  ∑PNs, a long-lived NOx reservoir whose concentration is supposed to be impacted by biomass burning emissions. In fire plumes, profiles of carbon monoxide (CO), which is a well-established tracer of pyrogenic emission, show concentration enhancements that are in strong correspondence with a significant increase of concentrations of ∑PNs, whereas minimal increase of the concentrations of O3 and NO2 is observed. The ∑PN and O3 productions have been calculated using the rate constants of the first- and second-order reactions of volatile organic compound (VOC) oxidation. The ∑PN and O3 productions have also been quantified by 0-D model simulation based on the Master Chemical Mechanism. Both methods show that in fire plumes the average production of ∑PNs and O3 are greater than in the background plumes, but the increase of ∑PN production is more pronounced than the O3 production. The average ∑PN production in fire plumes is from 7 to 12 times greater than in the background, whereas the average O3 production in fire plumes is from 2 to 5 times greater than in the background. These results suggest that, at least for boreal forest fires and for the measurements recorded during the BORTAS campaign, fire emissions impact both the oxidized NOy and O3,  but (1 ∑PN production is amplified significantly more than O3 production and (2) in the forest fire plumes the ratio between the O3 production and the ∑PN production is lower than the ratio evaluated in the background air masses, thus confirming that the role played by the ∑PNs produced during biomass burning is significant in the O3 budget. The implication of these observations is that fire emissions in some cases, for example boreal forest fires and in the conditions reported here, may influence more long-lived precursors of O3 than short-lived pollutants, which in turn can be transported and eventually diluted in a wide area.

scholarly journals Spatial and Temporal Distribution of Biomass Open Burning Emissions in the Greater Mekong Subregion

Climate ◽  
2020 ◽  
Vol 8 (8) ◽  
pp. 90
Author(s):  
Agapol Junpen ◽  
Jirataya Roemmontri ◽  
Athipthep Boonman ◽  
Penwadee Cheewaphongphan ◽  
Pham Thi Bich Thao ◽  
...  
Keyword(s):  
Fine Particulate Matter ◽  
Temporal Distribution ◽  
Landsat 8 ◽  
Total Biomass ◽  
Burnt Area ◽  
Fire Emissions ◽  
Vegetation Fires ◽  
Agricultural Burning ◽  
Burnt Areas ◽  
Greater Mekong Subregion

Moderate Resolution Imaging Spectroradiometer (MODIS) burnt area products are widely used to assess the damaged area after wildfires and agricultural burning have occurred. This study improved the accuracy of the assessment of the burnt areas by using the MCD45A1 and MCD64A1 burnt area products with the finer spatial resolution product from the Landsat-8 Operational Land Imager/Thermal Infrared Sensor (OLI/TIRS) surface reflectance data. Thus, more accurate wildfires and agricultural burning areas in the Greater Mekong Subregion (GMS) for the year 2015 as well as the estimation of the fire emissions were reported. In addition, the results from this study were compared with the data derived from the fourth version of the Global Fire Emissions Database (GFED) that included small fires (GFED4.1s). Upon analysis of the data of the burnt areas, it was found that the burnt areas obtained from the MCD64A1 and MCD45A1 had lower values than the reference fires for all vegetation fires. These results suggested multiplying the MCD64A1 and MCD45A1 for the GMS by the correction factors of 2.11−21.08 depending on the MODIS burnt area product and vegetation fires. After adjusting the burnt areas by the correction factor, the total biomass burnt area in the GMS during the year 2015 was about 33.3 million hectares (Mha), which caused the burning of 109 ± 22 million tons (Mt) of biomass. This burning emitted 178 ± 42 Mt of CO2, 469 ± 351 kilotons (kt) of CH4, 18 ± 3 kt of N2O, 9.4 ± 4.9 Mt of CO, 345 ± 206 kt of NOX, 46 ± 25 kt of SO2, 147 ± 117 kt of NH3, 820 ± 489 kt of PM2.5, 60 ± 32 kt of BC, and 350 ± 205 kt of OC. Furthermore, the emission results of fine particulate matter (PM2.5) in all countries were slightly lower than GFED4.1s in the range between 0.3 and 0.6 times.

scholarly journals Estimation of emissions from biomass burning in China (2003–2017) based on MODIS fire radiative energy data

2019 ◽  
Vol 16 (7) ◽  
pp. 1629-1640 ◽  
Author(s):  
Lifei Yin ◽  
Pin Du ◽  
Minsi Zhang ◽  
Mingxu Liu ◽  
Tingting Xu ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Forest Fires ◽  
Crop Residue ◽  
Crop Yields ◽  
Southern China ◽  
Farming System ◽  
Radiative Energy ◽  
Fire Emissions ◽  
The North ◽  
Significant Downward Trend

Abstract. Biomass burning plays a significant role in air pollution and climate change. In this study, we used a method based on fire radiative energy (FRE) to develop a biomass burning emission inventory for China from 2003 to 2017. Daily fire radiative power (FRP) data derived from 1 km MODIS Thermal Anomalies/Fire products (MOD14/MYD14) were used to calculate FRE and combusted biomass. Available emission factors were assigned to four biomass burning types: forest, cropland, grassland, and shrubland fires. The farming system and crop types in different temperate zones were taken into account in this research. Compared with traditional methods, the FRE method was found to provide a more reasonable estimate of emissions from small fires. The estimated average annual emission ranges, with a 90 % confidence interval, were 91.4 (72.7–108.8) Tg CO2 yr−1, 5.0 (2.3–7.8)  Tg CO yr−1, 0.24 (0.05–0.48) Tg CH4 yr−1, 1.43 (0.53–2.35) Tg NMHC yr−1, 0.23 (0.05–0.45) Tg NOx yr−1, 0.09 (0.02–0.17) Tg NH3 yr−1, 0.03 (0.01–0.05) Tg SO2 yr−1, 0.04 (0.01–0.08) Tg BC yr−1, 0.27 (0.07–0.49) Tg OC yr−1, 0.51 (0.19–0.84) Tg PM2.5 yr−1, 0.57 (0.15–1.05) Tg PM10 yr−1, where NMHC, BC, and OC are nonmethane hydrocarbons, black carbon, and organic carbon, respectively. Forest fires are determined to be the primary contributor to open fire emissions, accounting for 45 % of the total CO2 emissions (average 40.8 Tg yr−1). Crop residue burning ranked second place with a large portion of 39 % (average 35.3 Tg yr−1). During the study period, emissions from forest and grassland fires showed a significant downward trend. Crop residue emissions continued to rise during 2003–2015 but dropped by 42 % in 2015–2016. Emissions from shrubland were negligible and little changed. Forest and grassland fires are concentrated in northeastern China and southern China, especially in the dry season (from October to March of the following year). Plain areas with high crop yields, such as the North China Plain, experienced high agricultural fire emissions in harvest seasons. Most shrubland fires were located in Yunnan and Guangdong provinces. The resolution of our inventory (daily, 1 km) is much higher than previous inventories, such as GFED4s and GFASv1.0. It could be used in global and regional air quality modeling.

An integrated numerical system to estimate air quality effects of forest fires

2004 ◽  
Vol 13 (2) ◽  
pp. 217 ◽  
Author(s):  
A. I. Miranda
Keyword(s):  
Air Quality ◽  
Forest Fires ◽  
World Health ◽  
Plume Dispersion ◽  
Photochemical Pollution ◽  
Meteorological Model ◽  
Atmospheric Flow ◽  
Fire Emissions ◽  
Spread Model ◽  
Smoke Dispersion

Forest fires are an important source of various gases and particles emitted into the atmosphere that may affect the air quality on a local and/or larger scale. Currently, there is a growing awareness that smoke from wildland fires exposes individuals and populations to hazardous air pollutants. In order to understand and to simulate forest fire effects on air quality, several issues should be analysed and integrated: fire progression, fire emissions, atmospheric flow, smoke dispersion and chemical reactions. In spite of the available models to simulate smoke dispersion and the existence of some systems already covering the main questions, there still remains a lack of integration concerning fire progression. Photochemical pollution is also not included in these modelling systems. AIRFIRE is a numerical system, developed to estimate the effects of forest fires on air quality, integrating several components of the problem through the inclusion of different modules, namely the mesoscale meteorological model MEMO, the photochemical model MARS, and the Rothermel fire spread model. The system was applied to simulate plume dispersion from a wildfire that occurred in a coastal area, close to Lisbon city, at the end of September 1991. Results, namely the obtained pollutants concentration fields, point to a significant impact on the local air quality. Obtained wind fields and concentration patterns revealed the presence of sea breezes and also the influence of the fire in the atmospheric flow. Estimated carbon monoxide concentration levels were very high, exceeding the recommended hourly limit value of the World Health Organization, and ozone concentration values pointed to photochemical production.

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