Spacetime Distributions of Wildfire Areas and Emissions of Carbon-Containing Gases and Aerosols in Northern Eurasia according to Satellite-Monitoring Data

Based on online wildfire satellite-monitoring data, distributions of burned-out areas, as well as emission volumes of carbon-containing gases (СО and СО₂) and fine aerosols (РМ_2.5), for different regions and months in 2005–2016 (across the territory of Russia) and in 2010–2016 (northern Eurasia) are analyzed. Distinctive features of the seasonal behavior of wildfires and emission volumes of carbon-containing gases and fine aerosols for different regions of northern Eurasia are determined. It is shown that between 2005 and 2016 the annual area of territories burned out during wildfires in Russia decreased by almost a factor of 2.6 owing to early detection and suppression of fire sources. It is determined that in 2014–2016 the relative size of burned-out areas in Ukraine increased 6–9-fold and volumes of СО, СО₂, and РМ_2.5 emissions by more than a factor of 6.5–7.5 times when compared to earlier years and these characteristics for other European countries.     

Satellite monitoring of wildfires during the anomalous heat wave of 2010 in Russia

We describe the specific features of the summer 2010 emergency conditions in the European part of the Russian Federation, when an anomalous heat wave (the monthly mean temperatures in the summer months were 5–9°C higher than those for 2002–2009) and prolonged blocking anticyclones led to large wildfires. We analyze their causes and consequences. The features of the satellite system for operational fire monitoring (constructed at the Aerospace Scientific Center) and examples of its application in summer 2010 are presented. On the basis of the results of processing of satellite images of low (250–1000 m), medium (∼30–50 m), and high (∼6 m) resolutions, we found that the total area covered by fire from March to November of 2010 amounted to approximately 10.9 million hectares for the entire territory of the country and and 2.2 million hectares for its European part. Daily histograms of areas covered by fire in the summer months of 2010 were constructed. On the basis of these data and empirical models, we estimate the daily emissions of carbon monoxide (CO) from wildfires in the summer months of 2010 for the European part of Russia and Moscow oblast. On some days in August 2010, these emissions reached 15000–27000 t for the European part of Russia and 3000–7500 t for Moscow oblast. On the basis of analysis of data from the AIRS spectrometer (Aqua satellite), we derived the spatial distribution of CO concentrations at heights of 2 to 10 km above the territory of the Eastern and Central Europe. Moscow was shown to have been most severely affected by smoke from wildfires occurring on August 6–9, 2010, when the concentrations of harmful gases (CO₂, CO, CH₄, and O₃) and aerosols in the air significantly exceeded both the daily and the one-hour maximum allowable concentrations.     

Satellite Monitoring of Multiyear Wildfires and Related Emissions of Harmful Trace Gases into the Air Environment of Australia

Izvestiya, Atmospheric and Oceanic Physics - The results of wildfire satellite monitoring and estimates of the volumes of related emissions of CO and CO2 carbon-bearing trace gases and PM2.5 fine...     

Reduction of particulate matter and gaseous emission from marine diesel engines using a catalyzed particulate filter

Diesel engines are used widely as the power sources of coastal ships and international vessels primarily due to their high thermal efficiency, high fuel economy and durable performance. However, the gaseous and solid substances exhausted from diesel engines during the combustion process cause air pollution, in particular around harbor regions. In order to effectively reduce particulate matter and gaseous pollution emissions, a catalyzed particulate filter was equipped in the tail pipe of a marine diesel engine. The engine's performance and emission characteristics under various engine speeds and torques were measured using a computerized engine data control and acquisition system accompanied with an engine dynamometer. The effectiveness of installing a catalyzed particulate filter on the reduction of pollutant emissions was examined. The experimental results show that the exhaust gas temperature, carbon monoxide and smoke opacity were reduced significantly upon installation of the particulate filter. In particular, larger conversion of carbon monoxide to carbon dioxide — and thus larger CO₂ and lower CO emissions — were observed for the marine diesel engine equipped with a catalyzed particulate filter and operated at higher engine speeds. This is presumably due to enhancement of the catalytic oxidation reaction that results from an exhaust gas with stronger stirring motion passing through the filter. The absorption of partial heating energy from the exhaust gas by the physical structure of the particulate filter resulted in a reduction in the exhaust gas temperature. The particulate matter could be burnt to a greater extent due to the effect of the catalyst coated on the surface of the particulate filter. Moreover, the fuel consumption rate was increased slightly while the excess oxygen emission was somewhat decreased with the particulate filter.     

Carbon monoxide emissions in summer 2010 in the central part of the Russian Plain and estimation of their uncertainties with the use of different land-cover maps

This study is devoted to estimation of carbon monoxide (CO) emissions during the wildfires of the anomalously hot 2010 summer in the central part of the Russian Plain. CO emissions from the forest wildfires have been estimated with use of the Active Fires (AF) (MODIS MCD14ML) and Burned Areas (BA) (MODIS MCD45) methods for AVHRR/UDM, Global Land Cover 2000 (GLC 2000), GlobCover, and MCD12Q1 vegetation maps. A comparison of the vegetation maps and investigation of forest structure dynamics for the period from 2005 to 2009 have been carried out. It is shown that the major uncertainties during the estimation of CO in decreasing order are the following: distinctions in emission-calculation methods, differences in the vegetation maps used, differences in satellite data from Terra and Aqua, and the insufficient registration of forest structure dynamics. For additional comparison of estimations obtained by an independent method with the use of orbital (MOPITT, AIRS, and IASI) and ground-based (Moscow and Zvenigorod) spectroscopic measurements of CO content were presented.     

Satellite Monitoring of Burnt-out Areas and Emissions of Harmful Contaminants Due to Forest and Other Wildfires in Russia

Izvestiya, Atmospheric and Oceanic Physics - In this paper we summarize the results of the satellite monitoring of various types of wildfires, as well as emissions of carbon-containing the CO and...     

Effect of photochemical self-action of carbon-containing aerosol: Wildfires

It has been shown by numerical simulation that the rate of formation of secondary organic aerosols (SOAs) in smoke plumes caused by vegetation and peat fires under real conditions can significantly depend on the aerosol optical thickness (AOT). The AOT determines the photodissociation rate and hydroxyl radical concentration, which in turn determines the rate of SOA generation as a result of oxidation of semivolatile organic compounds. Quantitative analysis has been carried out for the situation that took place in European Russia during the 2010 Russian wildfires. The state-of-the-art 3D chemical transport model is used in this study; the simulations are optimized and validated using the data of monitoring of the particulate matter in the Moscow region and Finland. The findings indicate that it is important to allow for this effect in studies focused on the analysis and prediction of air pollution due to wildfires, as well as climate and weather studies, whose results may depend on the assumptions about the content and properties of atmospheric carbon-containing aerosol.     

Brown Carbon and Black Carbon in the Smoky Atmosphere during Boreal Forest Fires

We have investigated the variability of smoke aerosol absorbing ability with variations in the content of brown carbon (BrC) and black carbon (BC). Using monitoring data on radiative characteristics of smoke aerosol at AERONET stations and the spatial distribution of aerosol optical depth (AOD) obtained by the MODIS spectrometer (Terra satellite), we have detected large-scale smokes during boreal forest fires in Russia and Canada (1995–2012). The spatial distribution (50°–70° N, 95°–125° W) and temporal variability (at AERONET station Fort McMurray) of AOD during the smoking of a part of Canada in July 2012 have been analyzed. AOD probability distributions for July 14–18, 2012, and an estimate of aerosol radiative forcing of smoke aerosol at the upper boundary of the atmosphere have been obtained. We have proposed a technique for the diagnostics of BrC and BC in smoke aerosol particles from the spectral dependence of the imaginary part of the refractive index. At a wavelength of 440 nm, the contributions of BrC and BC to the smokeaerosol absorbing abitity can be comparable in magnitude. In many cases, the absorption spectra of smoke aerosol can be adequately approximated by either power or exponential functions. The presence of BrC in smoke-aerosol particles highly extends the variety of observed absorption spectra in a smoky atmosphere and spectral dependences of single scattering albedo. In the spectral range of 440–1020 nm, the radiative characteristics of smoke aerosol are largely contributed by its fine mode.     

On the influence of atmospheric chemical reactions on the ion composition of aerosol particles in the Baikal region

Monitoring data on the ion composition of aerosols and gas admixtures in the background and polluted atmosphere of the Lake Baikal region are presented. The ion composition and morphology of aerosols are affected by heterogeneous chemical reactions and variations in relative humidity. Two types of aerosol particles are revealed over this region. The fraction of solid particles recorded in most episodes includes primarily carbonates of alkaline and alkaline-earth metals. With increased atmospheric humidity, these particles are engaged in heterogeneous chemical reactions with gas-phase NH₃ and H₂SO₄, proceeding through the phase of watering. As a result, the composition of these aerosols is changed, and a fraction of aqueous H₂O/H₂SO₄/(NH₄)₂SO₄ aerosol particles of a different composition is formed. On the basis of a physical and chemical analysis of monitoring data on the aerosol composition and concentrations of gas admixtures, the average aerosol-size distribution of different types is estimated. For the first time, the mean acidity of aqueous aerosol particles is estimated.     

Methane, carbon monoxide, and carbon dioxide concentrations measured in the atmospheric surface layer over continental Russia in the TROICA experiments

The principal statistical regularities typical of the behaviors of the CH₄, CO, and CO₂ concentrations in the atmospheric surface layer over the continental Russian territory are revealed from the measurements performed in 1997–2004 along the Trans-Siberian Railroad from Moscow to Khabarovsk with a mobile laboratory. The data obtained under the conditions of the atmosphere free of anthropogenic pollutants are analyzed. For near-background conditions, the typical continental methane, carbon monoxide, and carbon dioxide concentrations and characteristic features of their large-scale spatial distributions and daily variations, including those caused by surface inversions, are determined. Variations in the concentrations of these trace gases over industrial regions are analyzed. Our results are compared to the data obtained at background stations of the world network of atmospheric monitoring and to the data of a numerical simulation.     

From reductionism to systems thinking: How the shipping sector can address sulphur regulation and tackle climate change

The shipping sector is required to reduce fuel sulphur content to 0.1% in Emission Control Areas by 2015 and to 0.5% globally by 2020. Although this is demanding, a greater challenge for all sectors is climate change. However, the three options to comply with sulphur regulation do little to address this challenge. With a deep-seated change to the type of fuel burnt in marine engines, this should be seen as an opportunity to explore co-benefits of sulphur and carbon reduction – instead of taking a short-sighted approach to the problem. It is argued here that the upcoming sulphur regulations should be postponed and instead, a co-ordinated suite of regulations should be implemented that tackles cumulative CO₂ emissions and localised SO_x emissions in chorus. This would ensure that less developed, yet more radical, step-change forms of propulsion such as wind, battery and biofuels are introduced from the outset – reducing the risks of infrastructure lock-in and preventing the lock-out of technologies that can meaningfully reduce absolute emissions from the sector.     

Regional space monitoring of nitrogen dioxide in the troposphere

Satellite instruments for the routine global monitoring of NO₂ in the atmosphere—the Global Ozone Monitoring Experiment (GOME) on the ERS-2 satellite, the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) on the ENVISAT satellite, the Ozone Monitoring Instrument (OMI) on the AURA satellite, and the GOME-2 on the MetOp satellite—are briefly described. It is shown that the error of measuring the NO₂ total column amount (∼10% for the background conditions in the troposphere) substantially increases in regions subject to anthropogenic pollution. Examples of practically using multiyear satellite measurements for the regional monitoring of NO₂ in the troposphere are presented, including mapping the tropospheric NO₂ in Russia, identifying the weekly and annual cycles in tropospheric NO₂ variations for megalopolises (St. Petersburg, Moscow, Paris), and estimating the long-term linear trend in 1995–2007.     

Mud volcanoes—a significant source of atmospheric methane

Mud volcanoes are recognized as a significant geological source of atmospheric carbon, particularly as methane gas. This paper considers the total number of mud volcanoes, types and frequency of their activity, quantities of emissions during quiescence and eruption, and composition of venting gases. Mud volcanoes approximate 1,950 prominent individuals worldwide and about 60 to 65 erupt every year. They sporadically or continuously emit to the atmosphere considerable volumes of gas, mainly methane, in average volumes of 3.3 to 3.6×10⁶ m³ per year during quiescent periods, and about 12×10⁶ m³ to more than 350×10⁶ m³ per single eruption. The total annual amount of methane emitted to the atmosphere through mud volcanoes is estimated to be about 5 Tg, containing almost equal quantities of fossil and modern carbon.     

Climate and carbon cycle variations in the 20th and 21st centuries in a model of intermediate complexity

The climate model of intermediate complexity developed at the Oboukhov Institute of Atmospheric Physics, Russian Academy of Sciences (IAP RAS CM), has been supplemented by a zero-dimensional carbon cycle model. With the carbon dioxide emissions prescribed for the second half of the 19th century and for the 20th century, the model satisfactorily reproduces characteristics of the carbon cycle over this period. However, with continued anthropogenic CO₂ emissions (SRES scenarios A1B, A2, B1, and B2), the climate-carbon cycle feedback in the model leads to an additional atmospheric CO₂ increase (in comparison with the case where the influence of climate changes on the carbon exchange between the atmosphere and the underlying surface is disregarded). This additional increase is varied in the range 67–90 ppmv depending on the scenario and is mainly due to the dynamics of soil carbon storage. The climate-carbon cycle feedback parameter varies nonmonotonically with time. Positions of its extremes separate characteristic periods of the change in the intensity of anthropogenic emissions and of climate variations. By the end of the 21st century, depending on the emission scenario, the carbon dioxide concentration is expected to increase to 615–875 ppmv and the global temperature will rise by 2.4–3.4 K relative to the preindustrial value. In the 20th–21st centuries, a general growth of the buildup of carbon dioxide in the atmosphere and ocean and its reduction in terrestrial ecosystems can be expected. In general, by the end of the 21st century, the more aggressive emission scenarios are characterized by a smaller climate-carbon cycle feedback parameter, a lower sensitivity of climate to a single increase in the atmospheric concentration of carbon dioxide, a larger fraction of anthropogenic emissions stored in the atmosphere and the ocean, and a smaller fraction of emissions in terrestrial ecosystems.     

Anomalous Wildfires in Siberia in Summer 2019

Izvestiya, Atmospheric and Oceanic Physics - The results of satellite wildfire monitoring and estimates for the amounts of emissions of harmful gases and fine aerosols in Siberia from 2001 to 2019...     

Validation of aerosol products derived from ocean colour in East African coastal waters

The aerosol products derived from the ocean colour missions SeaWiFS and MODIS (Aqua and Terra) were assessed with AERONET field measurements collected at sites in Mozambique (Inhaca) and Kenya (Malindi). The median of absolute relative differences between satellite and AERONET aerosol optical thickness τ_a at 443 nm varied between 12% and 22% for the different missions and sites. These differences tended to be higher at Malindi and for longer wavelengths. This analysis was supplemented by data collected offshore in the framework of the Maritime Aerosol Network. Results showed a general consistency between satellite missions and with global validation statistics. This suggests that the uncertainties associated with the atmospheric correction scheme and consequently with the distributions of ocean colour reflectance in the study area may be compared with those found in other regions. This result lends some confidence to the use of ocean colour data in the coastal waters of south-eastern Africa.     

Distributions of low molecular weight dicarboxylic acids in the North Pacific aerosol samples

Marine aerosol samples collected from the North Pacific atmosphere were studied for molecular distributions of dicarboxylic acids by using a capillary gas chromatography and mass spectrometery. A homologous series of dicarboxylic acids (C₂–C₁₀) was detected in the marine aerosol samples as dibutyl esters. All the samples showed that the smallest diacid (oxalic acid: C₂) was the most abundant and comprised 41–67% of the total diacids. The second most abundant species was malonic acid (C₃) or succinic acid (C₄). The diacids with more carbon numbers were generally less abundant. Total diacid concentration range was 17–1040 ng m^–3, which accounted for up to 1.6% of total aerosol mass. This indicates that low molecular weight dicarboxylic acids are important class of organic compounds in the marine atmosphere. The concentrations were generally higher in the western North Pacific and lower in the central North Pacific. The major portion of diacids is probably derived from the Asian Continent and East Asian countries by long-range atmospheric transport and partly fromin situ photochemical production in the marine atmosphere.     

Estimates of carbon monoxide emissions from wildfires in northern Eurasia for airquality assessment and climate modeling

The emissions from fires in the boreal zone of northern Eurasia significantly contribute to the global emissions of greenhouse gases, their precursors, and aerosols. These emissions are an important component of the global carbon balance, and they significantly affect both seasonal and long-term variations in the chemical composition and radiation properties of the atmosphere on both regional and global scales. The atmospheric emissions of carbon monoxide (CO) from biomass burning have systematically been estimated for the entire territory of northern Eurasia over the period of 2000–2008 on the basis of satellite (MODIS MCD45A1) data on burned vegetation and the Seiler-Crutzen emission model with consideration for both regional and seasonal features. On the whole, for Russia, the annual emissions of CO from biomass burning ranged from 10.6 to 88.2 Mt/y over the indicated period. Depending on fire activity, the atmospheric emissions of CO from natural fires and agricultural work may yield from 25 to 200% of the total technogenic emissions according to the EDGAR-2000 model. In this case, the dominant contribution is made by boreal forest fires (8–57 Mt/y), whose portion amounts to 63–76% of the total emissions from biomass burning. This relatively short observational series does not allow one to reliably estimate long-term variations; however, on the whole, a stable increase in burned areas has been observed in forest, steppe, and agricultural regions over the last decade. Our analysis suggests significant spatial and seasonal variations in the large-scale fields of fire emissions, which are determined by the physical, geographic, and climatic features of individual regions. The calculated fields of emissions can be used in transport-chemical models, studies of the regional transport and quality of air, and climate models.     

Estimating the efficiency of mitigating and preventing global warming with scenarios of controlled aerosol emissions into the stratosphere

Ensemble numerical experiments with the climate model of intermediate complexity developed at the A.M. Obukhov Institute of Atmospheric Physics of the Russian Academy of Sciences (IAP RAS CM) are conducted to estimate the efficiency of controlled climate forcing (geoengineering) due to stratospheric sulfate aerosol (SSA) emissions in order to compensate for global warming under the SRES A1B anthropogenic emission scenario. Full (or even excessive) compensation for the expected anthropogenic warming in the model is possible with sufficiently intense geoengineering. For ensemble members with values of the governing parameters corresponding to those obtained for the Mt. Pinatubo eruption, global warming is reduced by no more than 0.46 K in the second half of the 21st century, with a residual rise in the global surface temperature T _g comparative to 1961–1990 of 1.0–1.2 K by 2050 and 1.9–2.2 K by 2100. The largest reduction in global warming (with the other parameters of the numerical experiment being equal) is found not for a meridional distribution of SSA concentration peaked at low latitudes (despite the largest (in magnitude) global compensation instantaneous radiative forcing), but for a uniform horizontal aerosol distribution and for a distribution with the SSA concentration maximum in the middle and subpolar latitudes of the Northern Hemisphere. The efficiency of geoengineering in terms of T _g in the second half of the 21st century between the most efficient and the least efficient meridional distributions of stratospheric aerosols differs by as much as one-third, depending on the values of other governing parameters. For meridional distributions of SSA concentration, which produce the largest deceleration of global warming, such a deceleration is regionally most pronounced over high- and subpolarlatitude land areas and in the Arctic. In particular, this is expressed in the smallest reduction in the sea-ice extent and permafrost area under climate warming in the model. The compensation forcing also decelerates a general increase in global annual precipitation P _g during warming. The relative deceleration in precipitation increase is most pronounced in land regions outside the tropics, where a significant deficit in precipitation is currently observed. After the theoretical completion of geoengineering in the first or second decade, its temperature effect vanishes with an abrupt acceleration of global and regional surface warming. For individual members of the ensemble experiment, the global temperature change in this period is five times as large as that in the experiment without geoengineering and ten times as large regionally (in northeastern Siberia).     

Organic tracers from biomass burning in atmospheric particulate matter over the ocean

Particulate matter from the atmosphere over the Atlantic Ocean along the South American and African Continents has been analyzed for organic tracers from natural and biomass burning emissions. The major biomarker compounds characterized are natural products from continental vegetation consisting primarily of epicuticular wax components. For example, n-alkanes ranged from C₂₅ to C₃₅, with an odd carbon number predominance and carbon maxima (C_max) at 29 or 31. Concentrations of n-alkanes varied from 0.3 to 680 ng/m³. Nevertheless, n-alkanols are the dominant terrestrial tracers in almost all samples (concentrations from 0.1 to 780 ng/m³) and ranged from C₂₂ to C₃₄ with an even carbon number predominance. Despite the major presence of the natural tracers, organic components from biomass burning emissions are also present in the particulate matter. The major tracers from this source are thermal degradation products from the biopolymer cellulose, namely the dianhydromonosaccharide derivatives levoglucosan, galactosan, and mannosan. In general, the concentrations of levoglucosan, the major derivative from this source in all samples, varied from 0.0008 to 0.15 ng/m³ in atmospheric samples collected over the ocean and from 0.04 to 4860 ng/m³ in terrestrial particulate matter, used as reference in this study. Dehydroabietic acid, another marker compound emitted from burning of Gymnosperm fuel, is also detectable in most oceanic samples at concentrations ranging from 0.0001 to 0.4 ng/m³, whereas in terrestrial aerosol particulate matter, this component is present at much higher concentrations (0.23–440 ng/m³). The presence of these tracers in atmospheric particulate matter over the ocean confirms the long-range transport of smoke from biomass burning off the continents.