scholarly journals Transport of anthropogenic and biomass burning aerosols from Europe to the Arctic during spring 2008

2014 ◽  
Vol 14 (21) ◽  
pp. 28333-28384
Author(s):  
L. Marelle ◽  
J.-C. Raut ◽  
J. L. Thomas ◽  
K. S. Law ◽  
B. Quennehen ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Conveyor Belt ◽  
Airborne Lidar ◽  
Lagrangian Model ◽  
The Arctic ◽  
Aircraft Measurements ◽  
Source Regions ◽  
Vertical Distributions ◽  
Research Aircraft ◽  
European Arctic

Abstract. During the POLARCAT-France airborne campaign in April 2008, pollution originating from anthropogenic and biomass burning emissions was measured in the European Arctic. We compare these aircraft measurements with simulations using the WRF-Chem model to investigate model representation of aerosols transported from Europe to the Arctic. Modeled PM2.5 is evaluated using EMEP measurements in source regions and POLARCAT aircraft measurements in the Scandinavian Arctic, showing a good agreement, although the model overestimates nitrate and underestimates organic carbon in source regions. Using WRF-Chem in combination with the Lagrangian model FLEXPART-WRF, we find that during the campaign the research aircraft sampled two different types of European plumes: mixed anthropogenic and fire plumes from eastern Europe and Russia transported below 2 km, and anthropogenic plumes from central Europe uplifted by warm conveyor belt circulations to 5–6 km. Both modeled plume types had significant wet scavenging (> 50% PM10) during transport. Modeled aerosol vertical distributions and optical properties below the aircraft are evaluated in the Arctic using airborne LIDAR measurements. Evaluating the regional impacts in the Arctic of this event in terms of aerosol vertical structure, we find that during the 4 day presence of these aerosols in the lower European Arctic (< 75° N), biomass burning emissions have the strongest influence on concentrations between 2.5 and 3 km altitudes, while European anthropogenic emissions influence aerosols at both lower (~1.5 km) and higher altitudes (~4.5 km). As a proportion of PM2.5, modeled black carbon and SO4= concentrations are more enhanced near the surface. The European plumes sampled during POLARCAT-France were transported over the region of springtime snow cover in Northern Scandinavia, where they had a significant local atmospheric warming effect. We find that, during this transport event, the average modeled top of atmosphere (TOA) shortwave direct and semi-direct radiative effect (DSRE) north of 60° N over snow and ice-covered surfaces reaches +0.58 W m−2, peaking at +3.3 W m−2 at noon over Scandinavia and Finland.

scholarly journals Transport of anthropogenic and biomass burning aerosols from Europe to the Arctic during spring 2008

2015 ◽  
Vol 15 (7) ◽  
pp. 3831-3850 ◽  
Author(s):  
L. Marelle ◽  
J.-C. Raut ◽  
J. L. Thomas ◽  
K. S. Law ◽  
B. Quennehen ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Monitoring And Evaluation ◽  
Conveyor Belt ◽  
Airborne Lidar ◽  
Lagrangian Model ◽  
The Arctic ◽  
Aircraft Measurements ◽  
Source Regions ◽  
Vertical Distributions ◽  
Research Aircraft

Abstract. During the POLARCAT-France airborne campaign in April 2008, pollution originating from anthropogenic and biomass burning emissions was measured in the European Arctic. We compare these aircraft measurements with simulations using the WRF-Chem model to investigate model representation of aerosols transported from Europe to the Arctic. Modeled PM2.5 is evaluated using European Monitoring and Evaluation Programme (EMEP) measurements in source regions and POLARCAT aircraft measurements in the Scandinavian Arctic. Total PM2.5 agrees well with the measurements, although the model overestimates nitrate and underestimates organic carbon in source regions. Using WRF-Chem in combination with the Lagrangian model FLEXPART-WRF, we find that during the campaign the research aircraft sampled two different types of European plumes: mixed anthropogenic and fire plumes from eastern Europe and Russia transported below 2 km, and anthropogenic plumes from central Europe uplifted by warm conveyor belt circulations to 5–6 km. Both modeled plume types had undergone significant wet scavenging (> 50% PM10) during transport. Modeled aerosol vertical distributions and optical properties below the aircraft are evaluated in the Arctic using airborne lidar measurements. Model results show that the pollution event transported aerosols into the Arctic (> 66.6° N) for a 4-day period. During this 4-day period, biomass burning emissions have the strongest influence on concentrations between 2.5 and 3 km altitudes, while European anthropogenic emissions influence aerosols at both lower (~ 1.5 km) and higher altitudes (~ 4.5 km). As a proportion of PM2.5, modeled black carbon and SO4= concentrations are more enhanced near the surface in anthropogenic plumes. The European plumes sampled during the POLARCAT-France campaign were transported over the region of springtime snow cover in northern Scandinavia, where they had a significant local atmospheric warming effect. We find that, during this transport event, the average modeled top-of-atmosphere (TOA) shortwave direct and semi-direct radiative effect (DSRE) north of 60° N over snow and ice-covered surfaces reaches +0.58 W m−2, peaking at +3.3 W m−2 at noon over Scandinavia and Finland.

GLORIA observations of pollution tracers C2H6, C2H2, HCOOH, and PAN in the North Atlantic UTLS region

2020 ◽  
Author(s):  
Gerald Wetzel ◽  
Felix Friedl-Vallon ◽  
Norbert Glatthor ◽  
Jens-Uwe Grooß ◽  
Thomas Gulde ◽  
...  
Keyword(s):  
High Altitude ◽  
North Atlantic ◽  
Atmospheric Chemistry ◽  
Emission Spectra ◽  
Infrared Region ◽  
Reanalysis Data ◽  
Lagrangian Model ◽  
Back Trajectories ◽  
Source Regions ◽  
Research Aircraft

&lt;p&gt;The Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) is an imaging Fourier transform spectrometer (iFTS) using a 2-dimensional detector array to record emission spectra in the mid-infrared region with high spatial resolution. GLORIA is operated on high altitude research aircraft, mainly in the limb observational geometry to measure vertical profiles of temperature and atmospheric trace species with high vertical resolution.&lt;/p&gt;&lt;p&gt;In autumn 2017, the Wave-driven ISentropic Exchange (WISE) aircraft campaign took place from Shannon (Ireland). Sixteen flights with the High Altitude and Long Range Research Aircraft (HALO) were performed between 31 August and 21 October 2017 over the eastern North Atlantic region.&lt;/p&gt;&lt;p&gt;GLORIA observations were analysed with regard to pollutant species like C&lt;sub&gt;2&lt;/sub&gt;H&lt;sub&gt;6&lt;/sub&gt;, C&lt;sub&gt;2&lt;/sub&gt;H&lt;sub&gt;2&lt;/sub&gt;, HCOOH, and PAN, which are produced at distinct source regions near the ground and transported to remote regions due to their atmospheric lifetime of several weeks. Enhanced volume mixing ratios of these molecules were detected along some parts of the flight track in the upper troposphere and lowermost stratosphere (UTLS).&lt;/p&gt;&lt;p&gt;Measured profiles of these species are compared to simulations from the ECHAM/MESSy Atmospheric Chemistry (EMAC) model and reanalysis data from the Copernicus Atmosphere Monitoring Service (CAMS). Furthermore, emission tracers and back-trajectories from the Chemical Lagrangian Model of the Stratosphere (CLaMS) are used to analyse the source regions of these pollution events.&lt;/p&gt;

scholarly journals Source sector and region contributions to black carbon and PM<sub>2.5</sub> in the Arctic

2018 ◽  
Vol 18 (24) ◽  
pp. 18123-18148 ◽  
Author(s):  
Negin Sobhani ◽  
Sarika Kulkarni ◽  
Gregory R. Carmichael
Keyword(s):  
Black Carbon ◽  
Biomass Burning ◽  
Surface Concentration ◽  
The Arctic ◽  
Anthropogenic Emissions ◽  
Economic Sectors ◽  
Modeling Framework ◽  
Source Regions ◽  
Geographical Regions ◽  
Chinese Industry

Abstract. The impacts of black carbon (BC) and particulate matter with aerodynamic diameters less than 2.5 µm (PM2.5) emissions from different source sectors (e.g., transportation, power, industry, residential, and biomass burning) and geographic source regions (e.g., Europe, North America, China, Russia, central Asia, south Asia, and the Middle East) to Arctic BC and PM2.5 concentrations are investigated through a series of annual sensitivity simulations using the Weather Research and Forecasting – sulfur transport and deposition model (WRF-STEM) modeling framework. The simulations are validated using observations at two Arctic sites (Alert and Barrow Atmospheric Baseline Observatory), the Interagency Monitoring of Protected Visual Environments (IMPROVE) surface sites over the US, and aircraft observations over the Arctic during spring and summer 2008. Emissions from power, industrial, and biomass burning sectors are found to be the main contributors to the Arctic PM2.5 surface concentration, with contributions of ∼ 30 %, ∼ 25 %, and ∼ 20 %, respectively. In contrast, the residential and transportation sectors are identified as the major contributors to Arctic BC, with contributions of ∼ 38 % and ∼ 30 %. Anthropogenic emissions are the most dominant contributors (∼ 88 %) to the BC surface concentration over the Arctic annually; however, the contribution from biomass burning is significant over the summer (up to ∼ 50 %). Among all geographical regions, Europe and China have the highest contributions to the BC surface concentrations, with contributions of ∼ 46 % and ∼ 25 %, respectively. Industrial and power emissions had the highest contributions to the Arctic sulfate (SO4) surface concentration, with annual contributions of ∼ 43 % and ∼ 41 %, respectively. Further sensitivity runs show that, among various economic sectors of all geographic regions, European and Chinese residential sectors contribute to ∼ 25 % and ∼ 14 % of the Arctic average surface BC concentration. Emissions from the Chinese industry sector and European power sector contribute ∼ 12 % and ∼ 18 % of the Arctic surface sulfate concentration. For Arctic PM2.5, the anthropogenic emissions contribute > ∼ 75 % at the surface annually, with contributions of ∼ 25 % from Europe and ∼ 20 % from China; however, the contributions of biomass burning emissions are significant in particular during spring and summer. The contributions of each geographical region to the Arctic PM2.5 and BC vary significantly with altitude. The simulations show that the BC from China is transported to the Arctic in the midtroposphere, while BC from European emission sources are transported near the surface under 5 km, especially during winter.

Gust factor based on research aircraft measurements: a new methodology applied to the Arctic marine boundary layer

2016 ◽  
Vol 142 (701) ◽  
pp. 2985-3000 ◽  
Author(s):  
Irene Suomi ◽  
Christof Lüpkes ◽  
Jörg Hartmann ◽  
Timo Vihma ◽  
Sven-Erik Gryning ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Marine Boundary Layer ◽  
The Arctic ◽  
Aircraft Measurements ◽  
Gust Factor ◽  
Research Aircraft

scholarly journals Quantifying black carbon from biomass burning by means of levoglucosan – a one year time series at the Arctic observatory Zeppelin

2013 ◽  
Vol 13 (12) ◽  
pp. 31965-32003
Author(s):  
K. E. Yttri ◽  
C. Lund Myhre ◽  
S. Eckhardt ◽  
M. Fiebig ◽  
C. Dye ◽  
...  
Keyword(s):  
Time Series ◽  
Seasonal Variation ◽  
Black Carbon ◽  
Biomass Burning ◽  
Chemical Degradation ◽  
The Arctic ◽  
Wood Burning ◽  
European Arctic ◽  
One Year ◽  
Upper Estimate

Abstract. Levoglucosan, a highly specific tracer of particulate matter from biomass burning, has been used to study the influence of residential wood burning, agricultural waste burning and boreal forest fire emissions on the Arctic atmosphere black carbon (BC) concentration. A one year time series from March 2008 to March 2009 of levoglucosan has been established at the Zeppelin Observatory in the European Arctic. Elevated concentrations of levoglucosan in winter (Mean: 1.02 ng m−3) compared to summer (Mean: 0.13 ng m−3) were observed, resembling the seasonal variation seen for e.g. sulphate and BC. The mean concentration in the winter period was two to three orders of magnitude lower than typical values reported for European urban areas in winter, and one to two orders of magnitude lower than European rural background concentrations. Episodes of elevated levoglucosan concentration were more frequent in winter than in summer and peak values were higher, exceeding 10 ng m−3 at the most. Concentrations of elemental carbon from biomass burning (ECbb) were obtained by combining measured concentrations of levoglucosan and emission ratios of levoglucosan and EC for wild/agricultural fires and for residential wood burning. Neglecting chemical degradation by OH provides minimum levoglucosan concentrations, corresponding to a mean ECbb concentration of 3.7±1.2 ng m−3 in winter (October–April) and 0.8±0.3 ng m−3 in summer (May–September) or 8.8±4.5% of the measured equivalent black carbon (EBC) concentration in winter and 6.1±3.4% in summer. When accounting for chemical degradation of levoglucosan by OH, an upper estimate of 31–45% of EBC could be attributed to ECbb* (ECbb adjusted for chemical degradation) in winter and <65% in summer. Hence, fossil fuel sources appear to dominate the European Arctic BC concentrations in winter, whereas the very wide range obtained for summer does not allow us to conclude upon this for the warm season. Calculations using the Lagrangian particle dispersion model FLEXPART show that the seasonal variation of the modelled ECbb (ECbb,m) concentration compared relatively well with observationally derived ECbb from agricultural/wild fires during summer, and residential wood burning in winter. The model overestimates by a factor of 2.2 in winter and 4.4 in summer when compared to the observationally derived mean ECbb concentration, which provides the minimum estimate, whereas it underestimates by a factor of 2.3–3.3 in winter and a factor of 4.5 in summer when compared to ECbb*, which provides the upper estimate. There are indications of too low emissions of residential wood burning in Northern Russia, a region of great importance with respect to observed concentrations of BC in the European Arctic.

scholarly journals Atmospheric VOC measurements at a High Arctic site: characteristics and source apportionment

2021 ◽  
Vol 21 (4) ◽  
pp. 2895-2916
Author(s):  
Jakob B. Pernov ◽  
Rossana Bossi ◽  
Thibaut Lebourgeois ◽  
Jacob K. Nøjgaard ◽  
Rupert Holzinger ◽  
...  
Keyword(s):  
Source Apportionment ◽  
Biomass Burning ◽  
Atmospheric Chemistry ◽  
Dimethyl Sulfide ◽  
High Arctic ◽  
Anthropogenic Sources ◽  
The Arctic ◽  
Research Station ◽  
Source Regions ◽  
Arctic Haze

Abstract. There are few long-term datasets of volatile organic compounds (VOCs) in the High Arctic. Furthermore, knowledge about their source regions remains lacking. To address this matter, we report a multiseason dataset of highly time-resolved VOC measurements in the High Arctic from April to October 2018. We have utilized a combination of measurement and modeling techniques to characterize the mixing ratios, temporal patterns, and sources of VOCs at the Villum Research Station at Station Nord in northeastern Greenland. Atmospheric VOCs were measured using proton-transfer-reaction time-of-flight mass spectrometry. Ten ions were selected for source apportionment with the positive matrix factorization (PMF) receptor model. A four-factor solution to the PMF model was deemed optimal. The factors identified were biomass burning, marine cryosphere, background, and Arctic haze. The biomass burning factor described the variation of acetonitrile and benzene and peaked during August and September. The marine cryosphere factor was comprised of carboxylic acids (formic, acetic, and C3H6O2) as well as dimethyl sulfide (DMS). This factor displayed peak contributions during periods of snow and sea ice melt. A potential source contribution function (PSCF) showed that the source regions for this factor were the coasts around southeastern and northeastern Greenland. The background factor was temporally ubiquitous, with a slight decrease in the summer. This factor was not driven by any individual chemical species. The Arctic haze factor was dominated by benzene with contributions from oxygenated VOCs. This factor exhibited a maximum in the spring and minima during the summer and autumn. This temporal pattern and species profile are indicative of anthropogenic sources in the midlatitudes. This study provides seasonal characteristics and sources of VOCs and can help elucidate the processes affecting the atmospheric chemistry and biogeochemical feedback mechanisms in the High Arctic.

scholarly journals Vertical profile of atmospheric dimethyl sulfide in the Arctic Spring and Summer

2017 ◽  
Author(s):  
Roghayeh Ghahremaninezhad ◽  
Ann-Lise Norman ◽  
Betty Croft ◽  
Randall V. Martin ◽  
Jeffrey R. Pierce ◽  
...  
Keyword(s):  
Dimethyl Sulfide ◽  
Transport Model ◽  
Open Water ◽  
The Arctic ◽  
Chemical Transport Model ◽  
Air Mass ◽  
Baffin Bay ◽  
Mixing Ratios ◽  
Vertical Distributions ◽  
Research Aircraft

Abstract. Vertical distributions of atmospheric dimethyl sulfide (DMS(g)) were sampled aboard the research aircraft Polar 6 near Lancaster Sound, Nunavut, Canada in July 2014 and on pan-Arctic flights in April 2015 that started from Longyearbyen, Spitzbergen, and passed through Alert and Eureka, Nunavut and Inuvik, Northwest Territories. Larger mean DMS(g) mixing ratios were present during April 2015 (campaign-mean of 116±8 pptv) compared to July 2014 (campaign-mean of 20±6 pptv). Observations in July 2014 indicated a decrease in DMS(g) mixing ratios with altitude up to about 3 km, and the largest mixing ratios were found near the surface above ice-edge and open water, coincident with increased particle concentrations. In contrast, DMS(g) mixing ratios sampled in April 2015 were as high as 100 pptv near 2500 m. The April campaign also exhibited uniform campaign-mean vertical profiles overall although some profiles showed an increase with altitude. GEOS-Chem chemical-transport model simulations indicate that Arctic seawater (north of 66° N) contributes the majority of DMS(g) to the Arctic profiles (>90 %) in July 2014 flight tracks which were below 3000 m. More than 90 % of DMS(g) in April 2015 was from Arctic seawater for measurements below 500 m, but that declined to 60 % for altitudes between 500 m and 3000 m. FLEXPART simulations indicate that for summer 2014, the sampled air mass originated over Baffin Bay and the Canadian Arctic Archipelago. Whereas, for springtime 2015, the air mass sampled on flights near Alert and Eureka originated from Baffin Bay/Canadian Archipelago and from long-range transport (LRT) around the northern tip of Greenland. Our results highlight the role of open water below the flight as the source of DMS(g) during July 2014, and the influence of LRT of DMS(g) from further afield in the Arctic above 2500 m during April 2015.

scholarly journals Atmospheric VOC measurements at a High Arctic site: characteristics and source apportionment

2020 ◽  
Author(s):  
Jakob B. Pernov ◽  
Rossana Bossi ◽  
Thibaut Lebourgeois ◽  
Jacob K. Nøjgaard ◽  
Rupert Holzinger ◽  
...  
Keyword(s):  
Source Apportionment ◽  
Biomass Burning ◽  
High Arctic ◽  
Anthropogenic Sources ◽  
The Arctic ◽  
Back Trajectory ◽  
Research Station ◽  
Source Regions ◽  
Arctic Haze

Abstract. There are few long-term datasets of volatile organic compounds (VOCs) in the High Arctic. Furthermore, knowledge about their source regions remains lacking. To address this matter, we report a long-term dataset of highly time-resolved VOC measurements in the High Arctic from April to October 2018. We have utilized a combination of measurement and modeling techniques to characterize the mixing ratios, temporal patterns, and sources of VOCs at Villum Research Station at Station Nord, in Northeast Greenland. Atmospheric VOCs were measured using Proton Transfer-Time of Flight-Mass Spectrometry (PTR-ToF-MS). Ten ions were selected for source apportionment with the receptor model, positive matrix factorization (PMF). A four-factor solution to the PMF model was deemed optimal. The factors identified were Biomass Burning, Marine Cryosphere, Background, and Arctic Haze. The Biomass Burning factor described the variation of acetonitrile and benzene. Back trajectory analysis indicated the influence of active fires in North America and Eurasia. The Marine Cryosphere factor was comprised of carboxylic acids (formic, acetic, and propionic acid) as well as dimethyl sulfide (DMS). This factor displayed a clear diurnal profile during periods of snow and sea ice melt. Back trajectories showed that the source regions for this factor were the coasts around North Greenland and the Arctic Ocean. The Background factor was temporally ubiquitous, with a slight decrease in the summer. This factor was not driven by any individual chemical species. The Arctic Haze factor was dominated by benzene with contributions from oxygenated VOCs. This factor exhibited a maximum in the spring and minima during the summer and autumn. This temporal pattern and species profile are indicative of anthropogenic sources in the mid-latitudes. This study provides seasonal characteristics and sources of VOCs and can help elucidate the processes affecting the atmospheric chemistry and biogeochemical feedback mechanisms in the High Arctic.

scholarly journals Source Sector and Region Contributions to Black Carbon and PM<sub>2.5</sub> in the Arctic

2018 ◽  
Author(s):  
Negin Sobhani ◽  
Sarika Kulkarni ◽  
Gregory R. Carmichael
Keyword(s):  
Biomass Burning ◽  
Surface Concentration ◽  
The Arctic ◽  
Anthropogenic Emissions ◽  
Economic Sectors ◽  
Modeling Framework ◽  
Source Regions ◽  
Geographical Regions ◽  
Aircraft Observations ◽  
Pm2.5 Emissions

Abstract. The impacts of BC and PM2.5 emissions from different source sectors (e.g. transportation, power, industry, residential, and biomass burning) and source regions (e.g. Europe, North America, China, Russia, Central Asia, South Asia, and the Middle East) to Arctic BC and PM2.5 concentrations are investigated using a series of sensitivity runs with WRF-STEM modeling framework. The simulations are validated using aircraft observations over the Arctic during spring and summer 2008. Emissions from power, industrial, and biomass burning sectors are found to be the main contributors to the Arctic PM2.5 with contributions of ~ 30 %, ~ 25 %, and ~ 20 % respectively. In contrast, the residential and transportation sectors are identified as the major contributors to Arctic BC with contributions of ~ 38 % and ~ 30 %. Anthropogenic emissions are the most dominant contributors (~ 88 %) to the BC surface concentration over the Arctic; however, the contribution from biomass burning is significant over the summer (up to ~ 50 %). Among all geographical regions, Europe and China have the highest contributions to the BC surface concentrations with contributions of ~ 46 % and ~ 25 % respectively. Further sensitivity runs show that among various economic sectors of all geographic regions, European and Chinese residential sector contribute up to ~ 25 % and ~ 14 % to the Arctic average surface BC concentration. For Arctic PM2.5, the anthropogenic emissions contribute >~ 75 % at the surface annually, with contributions of ~ 25 % from Europe and ~ 20 % from China; however, the contributions of biomass burning emissions are significant in particular during spring and summer. The contributions of each geographical region to the Arctic PM2.5 and BC vary significantly with altitude. The simulations show that the BC from China is transported to the Arctic in the mid-troposphere, while, BC from European emission sources are transported near the surface under 5 km, especially during winter.

scholarly journals Quantifying black carbon from biomass burning by means of levoglucosan – a one-year time series at the Arctic observatory Zeppelin

2014 ◽  
Vol 14 (12) ◽  
pp. 6427-6442 ◽  
Author(s):  
K. E. Yttri ◽  
C. Lund Myhre ◽  
S. Eckhardt ◽  
M. Fiebig ◽  
C. Dye ◽  
...  
Keyword(s):  
Time Series ◽  
Seasonal Variation ◽  
Black Carbon ◽  
Biomass Burning ◽  
Chemical Degradation ◽  
The Arctic ◽  
Wood Burning ◽  
European Arctic ◽  
One Year ◽  
Upper Estimate

Abstract. Levoglucosan, a highly specific tracer of particulate matter from biomass burning, has been used to study the influence of residential wood burning, agricultural waste burning and Boreal forest fire emissions on the Arctic atmosphere black carbon (BC) concentration. A one-year time series from March 2008 to March 2009 of levoglucosan has been established at the Zeppelin observatory in the European Arctic. Elevated concentrations of levoglucosan in winter (mean: 1.02 ng m−3) compared to summer (mean: 0.13 ng m−3) were observed, resembling the seasonal variation seen for e.g. sulfate and BC. The mean concentration in the winter period was 2–3 orders of magnitude lower than typical values reported for European urban areas in winter, and 1–2 orders of magnitude lower than European rural background concentrations. Episodes of elevated levoglucosan concentration lasting from 1 to 6 days were more frequent in winter than in summer and peak values were higher, exceeding 10 ng m−3 at the most. Concentrations of elemental carbon from biomass burning (ECbb) were obtained by combining measured concentrations of levoglucosan and emission ratios of levoglucosan and EC for wildfires/agricultural fires and for residential wood burning. Neglecting chemical degradation by OH provides minimum levoglucosan concentrations, corresponding to a mean ECbb concentration of 3.7 ± 1.2 ng m−3 in winter (October–April) and 0.8 ± 0.3 ng m−3 in summer (May–September), or 8.8 ± 4.5% of the measured equivalent black carbon (EBC) concentration in winter and 6.1 ± 3.4% in summer. When accounting for chemical degradation of levoglucosan by OH, an upper estimate of 31–45% of EBC could be attributed to ECbb* (ECbb adjusted for chemical degradation) in winter, whereas no reliable (<100%) upper estimate could be provided for summer for the degradation rates applied. Hence, fossil fuel sources appear to dominate the European Arctic BC concentrations in winter, whereas the very wide range obtained for summer does not allow us to conclude upon this for the warm season. Calculations using the Lagrangian particle dispersion model FLEXPART show that the seasonal variation of the modeled ECbb (ECbb,m) concentration compared relatively well with observationally derived ECbb from agricultural fires/wildfires during summer, and residential wood burning in winter. The model overestimates by a factor of 2.2 in winter and 4.4 in summer when compared to the observationally derived mean ECbb concentration, which provides the minimum estimate, whereas it underestimates by a factor of 2.3–3.3 in winter and a factor of 4.5 in summer when compared to ECbb*, which provides the upper estimate. There are indications of too-low emissions of residential wood burning in northern Russia, a region of great importance with respect to observed concentrations of BC in the European Arctic.

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