Source: https://www.atmos-chem-phys.net/19/1393/2019/acp-19-1393-2019-relations.html
Timestamp: 2019-04-26 12:29:20+00:00

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We present the latest release of the Lagrangian transport model FLEXPART, which simulates the transport, diffusion, dry and wet deposition, radioactive decay and first order chemical reactions of atmospheric tracers. The model has been recently updated, both technical and in the representation of physico-chemical processes. We describe the changes, document the most recent input and output files, provide working examples and introduce testing capabilities.
We present BC inversions at high northern latitudes in 2013–2015. The emissions were high close to the gas flaring regions in Russia and in western Canada. The posterior emissions of BC at latitudes > 50° N were estimated as 560 ± 171 kt yr-1, smaller than in bottom-up inventories. Posterior concentrations over the Arctic compared with independent observations from flight and ship campaigns showed small biases. Seasonal maxima were estimated in summer months due to biomass burning, mainly in Europe.
We simulate CH4 and CO2 using a zoomed global transport model with a horizontal resolution of ~50 km over South and East Asia, as well as a standard model version for comparison. Model performance is evaluated for both gases and versions at multiple timescales against a new collection of surface stations over this key GHG-emitting region. The evaluation at different timescales and comparisons between gases and model versions have implications for possible model improvements and inversions.
We present EC measurements from an uncertain region in terms of emissions (Russia). Its origin is quantified with a Lagrangian model that uses a recently developed feature that allows backward estimation of the specific source locations that contribute to the deposited mass. In NW European Russia transportation and domestic combustion from Finland was important. A systematic underestimation was found in W Siberia at places where gas flaring was important, implying miscalculation or sources.
We extend the backward modelling technique in the existing model FLEXPART to substances deposited at the Earth’s surface by wet scavenging and dry deposition. This means that for existing measurements of a substance in snow, ice cores or rain samples the source regions can be determined. This will help the interpretation of the measurement as well as gaining information of emission strength at the source of the deposited substance.
This is the first paper that attempts to assess the source term of the Chernobyl accident using not only activity concentrations but also deposition measurements. This is done by using the FLEXPART model combined with a Bayesian inversion algorithm. Our results show that the altitude of the injection during the first days of the accident might have reached up to 3 km, in contrast to what has been already reported (2.2 km maximum), in order the model to better match observations.
We developed the most comprehensive dataset of daily BC emissions from forest, grassland, shrubland, and savanna fires over northern Eurasia at a 500 m × 500 m resolution from 2002 to 2015. We examined the daily, seasonal, and interannual variability of BC emissions from fires in different ecosystems in the geopolitical regions of Russia, eastern Asia, central and western Asia, and Europe. The results are essential for modeling the transport and deposition of fire-emitted BC to the Arctic.
Processes affecting aerosol removal from the atmosphere are not fully understood. In this study we investigate to what extent atmospheric transport models can reproduce observed loss of aerosols. We compare measurements of radioactive isotopes, that attached to ambient sulfate aerosols during the 2011 Fukushima nuclear accident, to 19 models using identical emissions. Results indicate aerosol removal that is too fast in most models, and apply to aerosols that have undergone long-range transport.
Natural and human-ignited fires affect all major biomes, and satellite observations provide evidence for rapid changes in global fire activity. The Global Fire Atlas of individual fire size, duration, speed, and direction is the first global data product on individual fire behavior. Moving towards a global understanding of individual fire behavior is a critical next step in fire research, required to understand how global fire regimes are changing in response to land management and climate.
Carbonaceous aerosols from natural sources were abundant regardless of season. Residential wood burning (RWB) emissions were occasionally equally as large as or larger than of fossil-fuel sources, depending on season and region. RWB emissions are poorly constrained; thus emissions inventories need improvement. Harmonizing emission factors between countries is likely the most important step to improve model calculations for biomass burning emissions and European PM2.5 concentrations in general.
This article presents the updated MAPIR algorithm, which uses infrared satellite data to obtain the global 3-D distribution of mineral aerosols. A description of the method together with its technical improvements is given. Additionally, a 10-year data set was generated and used to validate this new algorithm against AERONET, CALIOP, CATS and two ground-based lidar stations. We have shown that the new MAPIR algorithm provides reliable aerosol optical depth, dust layer mean altitude and profiles.
We measured atmospheric mixing ratios of methane over the Arctic Ocean around Svalbard and compared observed variations to inventories for anthropogenic, wetland, and biomass burning methane emissions and an atmospheric transport model. With knowledge of where variations were expected due to the aforementioned land-based emissions, we were able to identify and quantify a methane source from the ocean north of Svalbard, likely from sub-sea hydrocarbon seeps and/or gas hydrate decomposition.
This study presents an artificial release experiment aimed to improve the understanding of turbulence in the atmospheric boundary layer. A new set of image processing methods was developed to analyse the turbulent dispersion of sulfur dioxide (SO2) puffs. For this a tomographic setup of six SO2 cameras was used to image artificially released SO2 gas.
A Lagrangian particle dispersion model is used to simulate global fields of methane, constrained by observations through nudging. We show that this rather simple and computationally inexpensive method can give results similar to or as good as a computationally expensive Eulerian chemistry transport model with a data assimilation scheme. The three-dimensional methane fields are of interest to applications such as inverse modelling and satellite retrievals.
We use satellite data and model output to estimate how airborne particles (aerosols) affect cloud ice particles and droplets over the Arctic Ocean. Aerosols from sources like smoke and pollution can change cloud cover, precipitation frequency, and the portion of liquid- vs. ice-containing clouds, which in turn can impact the surface energy budget. By improving our understanding these aerosol–cloud interactions, this work can help climate predictions for the rapidly changing Arctic.
The aerosol layer height is one of four aerosol parameters which is needed to enhance our understanding of aerosols' role in the climate system. Both active and passive measurement methods may be used to estimate the aerosol layer height. Aerosol height estimates made from passive infrared and solar satellite sensors measurements are compared with satellite-borne lidar estimates. There is considerable variation between the retrieved dust heights and how they compare with the lidar.
We provide the scientific community with a SOFT-IO tool based on the coupling of Lagrangian modeling with emission inventories and aircraft CO measurements, which is able to calculate the contribution of the sources and geographical origins of CO measurements, with good performances. Calculated CO added-value products will help scientists in interpreting large IAGOS CO data set. SOFT-IO could further be applied to other CO data sets or used to help validate emission inventories.
In the fall of 2011, iodine-131 (131I) was detected at several radionuclide monitoring stations in central Europe. We estimate the source location and emission variation using only the available 131I measurements. Subsequently, we use the IAEA report about the source term for validation of our results. We find that our algorithm could successfully locate the actual release site. The findings are also in agreement with the values reported by the IAEA.
Observation of ice nuclei active at −8 °C show that rainfall drives their abundance throughout all seasons and that they are equally distributed amongst coarse and fine fraction of PM10. Concurrent measurements of fungal spore markers suggest that some fraction of INP-8 may consist of fungal spores during the warm part of the year. Snow cover suppresses the aerosolisation of ice nuclei. Changes in snow cover and rainfall may affect atmospheric concentrations of ice nuclei in future.
How much dust do Icelandic sources emit and where is this dust deposited? We modelled dust emission and transport from Icelandic sources over 27 years with FLEXPART. Results show that Icelandic dust sources can have emission rates similar to parts of the Sahara and considerable amounts of dust are deposited in the ocean and on glaciers.
An inversion method is tested in a forecasting setting for constraining ash dispersion by satellite observations. The sensitivity of a priori and satellite uncertainties is tested for the a posteriori term. The a posteriori is also tested with four different assumptions affecting the retrieved ash satellite data. In forecasting mode, the a posteriori changes after only 12 h of satellite observations and produces better forecasts than a priori.
We present the first use of spectrometer measurements from a drone to assess reflectance and albedo over the Greenland Ice Sheet. In order to measure albedo – a critical parameter in the earth's energy balance – a drone was flown along 200 km transects coincident with Terra and Aqua satellites flying MODIS. We present a direct comparison of UAV-measured reflectance with satellite data over Greenland and provide a new method to study cryospheric surfaces using UAV with spectral instruments.
Clouds have a major but uncertain effect on Arctic surface temperatures. Here, we used remote sensing observations to better understand aerosol effects on one type of Arctic cloud. By modifying a variety of cloud properties, aerosols in this type of cloud indirectly reduced the net warming effect of these clouds on the surface by ~ 10 % of the clean-background cloud effect, not including changes in cloud fraction. This work will improve our ability to predict future Arctic surface temperatures.
Ash deposits can be remobilized for years following a volcanic eruption, and the resulting resuspended ash clouds can pose a significant hazard to local populations and airports. The aim of this work is to improve our ability to forecast resuspended ash storms. We use satellite imagery to constrain the emission rate of resuspended particles in an atmospheric dispersion model used to forecast resuspension events in Iceland.
This work includes a study on the effects of dust deposition on the mass balance of Brúarjökull, an outlet glacier of Vatnajökull, Iceland's largest ice cap. A model was used to simulate dust deposition on the glacier, and these periods of dust were compared to albedo measurements at two weather stations on Brúarjökull to evaluate the dust impact. We determine the influence of dust events on the snow albedo and the surface energy balance.
Methane (CH4) fluxes were estimated for the high northern latitudes for 2005–2013 based on observations of atmospheric CH4 mixing ratios. Methane fluxes were found to be higher than prior estimates in northern Eurasia and Canada, especially in the Western Siberian Lowlands and the Canadian province Alberta. Significant inter-annual variations in the fluxes were found as well as a small positive trend. In Canada, the trend may be related to an increase in soil temperature over the study period.
Estimation of pollutant releases into the atmosphere is an important problem in the environmental sciences. We formulate a probabilistic model, where a full Bayesian estimation allows estimation of all tuning parameters from the measurements. The proposed algorithm is tested and compared with the state-of-the-art method on data from the European Tracer Experiment (ETEX), where advantages of the new method are demonstrated.
Increasing wildfire activities in the mountainous western US may present a challenge for the region to attain a recently revised ozone air quality standard in summer. We quantify the wildfire influence on the ozone variability, trends, and number of high ozone days over this region in summers 1989–2010 using a Lagrangian dispersion model and statistical regression models.
FLEXPART is a community model used by many scientists. Here, an alternative FLEXPART model version has been developed, tailored to use with the output data generated by the Norwegian Earth System Model (NorESM1-M). The model provides an advanced tool to analyse and diagnose atmospheric transport properties of the climate model NorESM. To validate the model, several tests were performed that offered the possibility to investigate some aspects of offline global dispersion modelling.
During volcanic eruptions the presence of ice clouds may affect the volcanic ash signal in infrared satellite measurements. By comparison of measured infrared spectra with spectra from a radiative transfer model including both ash and ice clouds, it is shown that during the Mt Kelud February 2014 eruption, both ash and ice clouds were present simultaneously. The presence of ice clouds lowers the estimated amount of volcanic ash in the atmosphere.
We analyze interactions of Arctic clouds with pollution plumes that have been transported long distances from midlatitudes. Constraining for meteorological state, we find that pollution decreases cloud-droplet effective radius and increases cloud optical depth. The impact is highest when the atmosphere is particularly humid and/or stable suggesting that aerosol–cloud interactions depend on the Arctic's climate.
This is the first study reporting top-down estimates of benzene and toluene emissions in southern China using atmospheric measurement data from a rural site in the area, an atmospheric transport model and an inverse modeling method. This study shows in detail the temporal and spatial differences between the inversion estimate and four different bottom-up emission inventories (RCP, REAS, MEIC; Yin et al., 2015). We propose that more observations are urgently needed in future.
The magnitude and makeup of error in cryospheric radiation observations due to small sensor misalignment in in situ measurements of solar irradiance is evaluated. It is shown that relatively minor sensor misalignments give significant errors in irradiance and hence albedo measurements. The total measurement error introduced by sensor tilt is dominated by the direct component. Significant measurement error can also persist in integrated daily irradiance and albedo.
Landscape fire plume height controls fire emissions release in the atmosphere, in particular their transport that may also affect the longevity, chemical conversion, and fate of the plumes chemical constituents. Here, we review how such landscape-scale fire smoke plume injection heights are represented in large-scale atmospheric transport models aiming to represent the impacts of wildfire emissions on component of the Earth system.
This paper presents a summary of the findings of the ECLIPSE EU project. The project has investigated the climate and air quality impacts of short-lived climate pollutants (especially methane, ozone, aerosols) and has designed a global mitigation strategy that maximizes co-benefits between air quality and climate policy. Transient climate model simulations allowed quantifying the impacts on temperature (e.g., reduction in global warming by 0.22K for the decade 2041-2050) and precipitation.
A detailed characterization of air quality in the Paris (France) agglomeration, a megacity, during two summer and winter intensive campaigns and from additional 1-year observations, revealed that about 70% of the fine particulate matter (PM) at urban background is transported into the megacity from upwind regions. Unexpectedly, a major part of organic PM is of modern origin (woodburning and cooking activities, secondary formation from biogenic VOC).
The concentrations of sulfate, black carbon and other aerosols in the Arctic are characterized by high values in late winter and spring (so-called Arctic Haze) and low values in summer. Models have long been struggling to capture this seasonality. In this study, we evaluate sulfate and BC concentrations from different updated models and emissions against a comprehensive pan-Arctic measurement data set. We find that the models improved but still struggle to get the maximum concentrations.
Water and ice clouds affect detection and retrieval of volcanic ash clouds by satellite instruments. Synthetic infrared satellite images were generated for the Eyjafjallajokull 2010 and Grimsvotn 2011 eruptions by combining weather forecast, ash transport and radiative transfer modelling. Clouds decreased the number of pixels identified as ash and generally increased the retrieved ash-mass loading compared to the cloudless case; however, large differences were seen between scenes.
The transport of Biomass Burning emissions in Chemical Transport Model rely on parametrization of plumes injection height. Using fire observation selected to ensure match-up of fire-atmosphere-plume dynamics; a popular plume rise model was improved and optimized. The resulting model shows response to the effect of atmospheric stability consistent with previous findings and is able to predict higher injection height than any other tested parametrizations, giving a closer match with observation.
How stratospheric are deep stratospheric intrusions?
The influence of cruise ship emissions on air pollution in Svalbard – a harbinger of a more polluted Arctic?
We have modelled biomass burning haze concentrations in Singapore between 2010 and 2015. The major contributing haze source regions at two monitoring stations located in the western and eastern part of Singapore, less than 30 km apart, show significant variation on seasonal and annual timescales, as well as between the stations. Our results show that haze concentrations in Singapore are driven by a combination of local and regional weather, climate, and the location of regional burning.
The model is able to represent LWP but not the LCF. AOD is consistent over the continent but also over ocean (ACAOD). Differences are observed in SSA due to the absence of internal mixing in ALADIN-Climate. A significant regional gradient of the forcing at TOA is observed. An intense positive forcing is simulated over Gabon. Results highlight the significant effect of enhanced moisture on BBA extinction. The surface dimming modifies the energy budget.
In this study, an Earth system model has been used to investigate climate feedbacks associated with increasing BVOC emissions due to higher CO2 concentrations and temperatures. Higher BVOC emissions associated with a changed climate are found to induce an important negative climate feedback through increased aerosol formation and resulting changes in cloud properties. This feedback is found to have the potential to offset about 13 % of the radiative forcing associated with a doubling of CO2.
In this study, we found that a cold front can transport air pollutants from the polluted North China Plain to the Yangtze River Delta (YRD), thereby deteriorating air quality over the YRD. Before the cold frontal passage, a warm and polluted air mass over YRD climbed to the free troposphere (1.0–2.0 km) along the frontal surface. After the cold frontal passage, high pressure behind the frontal zone resulted in a synoptic subsidence that trapped PM2.5 in the surface.
A global chemical-transport model is used to determine the impact of methanesulfonic acid (MSA) on the aerosol size distribution and associated radiative effects, testing varying assumptions of MSA’s effective volatility and nucleating ability. We find that MSA mass best matches the ATom airborne measurements when volatility varies as a function of temperature, relative humidity, and available gas-phase bases, and the MSA radiative forcing is on the order of -50 mW m-2 over the Southern Ocean.
The main uncertainties regarding the estimation of changes in the Earth’s energy budget are related to the role of atmospheric aerosols. Our study evaluates the representation of aerosol optical properties by different atmospheric chemistry models against remote-sensing observations in order to reduce this uncertainty. Results show that the representation of aerosol optical properties is strongly dependent on the used model.
Black carbon (BC) possesses complex minor structures besides the overall aggregate geometry, thus altering their optical properties. This study introduces volume variation to quantify and unify different minor structures and develops an empirical relation to account for their effects on BC optical properties. We find the effects of minor structures are mainly contributed by their influence on particle volume/mass, and a relative difference of 5 % is noticed after removing volume differences.
Long-term aerosol measurements from the IMPROVE network were used to investigate the simulation of mass scattering efficiency in the GEOS-Chem chemical transport model. The simulation of mass scattering efficiency was developed to better represent observations by refining the representation of aerosol size and hygroscopicity. Simulated average mass scattering efficiency over North America increased by 16 %, with larger increases in northern regions and reductions in the southwest.
The present study provided information on specific glaciers over the Hindu Kush Himalayan region identified as being vulnerable to BC-induced impacts (affected by high BC-induced snow albedo reduction in addition to being sensitive to BC-induced impacts), thus impacting the downstream hydrology. The source-specific contribution to atmospheric BC aerosols by emission sources led to identifying the potential emission source, which was distinctive over south and north to 30° N.
Black carbon (BC) particles exert a potentially large warming influence on the Earth system. We evaluate regional climate responses, non-linearity, and short-term transient responses to BC emission perturbations. We found that climate responses do not scale linearity with emissions and BC impacts temperature much faster than greenhouse gas forcing. Removing present-day BC emissions results in discernible surface temperature changes for only limited regions of the globe.
We use a global climate model to study how anthropogenic emissions of short-lived atmospheric particles in different parts of the world influence the global temperature distribution. We find that the global mean temperature change per unit emission is similar for all emission regions, and the largest temperature response is found in the Arctic no matter where the emissions occur. However, for European emissions, the temperature change per unit emission is found to depend on emission strength.
Using MERRA-2 reanalysis daily data from 2001 to 2015, we found that during strong South Asian summer monsoon years, the Asian monsoon anticyclone is more expansive and shifted northward. All the CO, carbonaceous aerosols and dust are found to be more abundant in the Asian Tropopause Aerosol Layer (ATAL). ATAL trends are associated with increasing strength of the AMA, with earlier and enhanced vertical transport of ATAL constituents by enhanced overshooting convection over the transport regions.
Asian dust is one of the important components in modern and past climate change via its effects, including snow-darkening and direct radiation. We employed model experiments to evaluate these effects on Indian monsoon and found that the monsoon onset responds significantly to both. Snow-darkening effect weakens the monsoon, but direct radiative effect intensifies it. Besides the previous Tibetan Plateau studies proposed, our work highlights the importance of temperature change over dust sources.
In this study, we fully describe black carbon wet removal coupled with all cloud processes from a cloud microphysics scheme in a climate model and conduct sensitivity simulations that turn off each cloud process one at a time. We find that convective scavenging, aerosol activation, ice nucleation, evaporation of rain–snow, and below-cloud scavenging dominate wet deposition of BC. In addition, the range of direct radiative forcing derived from sensitivity simulations is large, 0.09–0.33 W m−2.
Timescales for secondary organic aerosols to reach equilibrium were estimated under various temperatures and relative humidities. Equilibration timescales in the free troposphere can be longer than hours or days even at moderate or relatively high relative humidity. These results provide critical insights into thermodynamic or kinetic treatments of SOA partitioning for accurate predictions of gas- and particle-phase concentrations of semi-volatile compounds in chemical transport models.
Assumptions (ideality and thermodynamic equilibrium) commonly made in 3-dimensional air quality models were reconsidered to evaluate their impacts on secondary organic aerosol (SOA) formation. Non-ideality (short-, medium- and long-range interactions of organics and inorganics) influences SOA concentrations by about 30 % over Europe. If SOA are highly viscous rather than inviscid, hydrophobic SOA concentrations increase by 6 % but can increase by an order of magnitude for volatile compounds.
Diffuse light can increase the efficiency of vegetation photosynthesis. Diffuse light results from scattering by either clouds or aerosols in the atmosphere. During the dry season biomass burning (BB) on the edges of the Amazon rainforest contributes significantly to the aerosol burden over the entire region. We show that despite a modest effect of change in light conditions, the overall impact of BB aerosols on the vegetation is still important when indirect climate feedbacks are considered.
Atmospheric carbonaceous aerosols are able to absorb solar radiation and they continue to contribute some of the largest uncertainties in projected climate change. One important detail is how the chemical species are arranged inside each particle, i.e. the knowledge of their mixing state. We use an ensemble of regional model simulations to test different mixing state assumptions and found that a combination of internal and external mixing may better reproduce sunphotometer observations.
In climate models, organic carbon (OC) in wildfire smoke has been treated as an atmospheric cooling component by reflecting sunlight back to space. This study incorporates the observationally identified absorbing brown carbon component of OC into the Community Earth System Model, improving the agreement between the model and observations and effectively increasing absorption of solar radiation. This change contributes to altered atmospheric dynamics and changes in cloud cover in the model.
The explosive growth (EG) of PM2.5 resulted in a PM2.5 maximum, which was generally underestimated by atmospheric chemical models due to the deficient description of the local turbulence intermittent . The aerosol–radiation feedback (AF) and decrease in turbulence diffusion (DTD) may reduce the underestimation of PM2.5 EG by 20–25% and 14–20%, respectively. The modeled EG stage PM2.5 error was decreased from −40 to −51% to −11 to 2% by the combined effects of AF and DTD in Jing–Jin–Ji.
The impact of desert dust on cloud formation is investigated for a major Saharan dust event over Europe by interactive regional dust modeling. Dust particles are very efficient ice-nucleating particles promoting the formation of ice crystals in clouds. The simulations show that the observed extensive cirrus development was likely related to the above-average dust load. The interactive dust–cloud feedback in the model significantly improves the agreement with aircraft and satellite observations.
The most important number for future climate projections is Earth's climate sensitivity (CS), or how much warming will result from increased carbon dioxide. We cannot know the true CS, and estimates of CS from climate models have a wide range. This study identifies the major factors that control this range, and we show that the choice of methods used in creating a climate model are three times more important than fine-tuning the details of the model after it is created.
Aerosol nucleation exerts important influences on the climate, hydrological cycle, and air quality. We have developed an advanced physical–chemical model that describes ion-induced and neutral nucleation involving ammonia, sulfuric acid, and water vapors. The model is shown to reproduce laboratory measurements taken under a wide range of conditions, offers physiochemical insights into the ternary nucleation process, and provides an accurate approach to calculate ternary rate in the atmosphere.
An EnKF system was developed to simultaneously assimilate multiple surface measurements, including PM10, PM2.5, SO2, NO2, O3, and CO, via the joint adjustment of ICs and source emissions. Large improvements were achieved in the first 24 h forecast for PM2.5, PM10, SO2, and CO during an extreme haze episode that occurred in early October 2014 over the North China Plain, but no improvements were achieved for NO2 and O3.
The surface tension of aqueous NaCl (σ) is investigated by molecular dynamics simulations from dilute to highly supersaturated solutions. The linear approximation of concentration dependence of σ at molality scale can be extended to the supersaturated NaCl solution until the solute mass fraction (xNaCl) of ~0.39. After that, the σ remains almost unchanged until an xNaCl of ~0.47. Then the σ gradually regains the growing momentum with a tendency to approach the surface tension of molten NaCl.
This work develops a model for ice formation mediated by particles immersed within droplets. Ice nucleation is not only enhanced by the modification of the thermodynamic properties of the vicinal water but is also inhibited by decreased water mobility near the particle. The ice nucleation rate is thus determined by competing kinetic and thermodynamic factors during ice formation. A new regime where ice nucleation is mediated mainly by kinetics instead of thermodynamics is discovered.
The absorption enhancement of black carbon with brown coatings is investigated. In addition, the ratio of the absorption of BC coated by brown carbon (BrC) to an external mixture of BrC and BC (Eabs_internal) is also investigated. The lensing effect and sunglasses effect are clearly defined. The applicability of the core–shell sphere model was investigated. The effects of the size distribution, fractal dimension, and wavelength dependency are also explored.
International shipping emissions (ISE) can influence the global radiation budget. Using an Earth system model, we derive a significant global cloud radiative effect (CRE) of ISE (−0.153 W m−2) when using current emissions. This CRE would become weaker (−0.001 W m−2) if a more stringent regulation were adopted. The CRE would achieve a significant enhancement when a lower DMS emission is prescribed. These findings suggest a reevaluation of the ISE-induced CRE with consideration of DMS variability.
This paper discusses the importance of aerosol water for aerosol optical depth calculations using a long-term evaluation of the global chemistry climate and Earth system model EMAC through a comparison of EQSAM4clim and ISORROPIA II with observations at climate timescales. Sensitivity studies with different levels of chemical aging and associated water uptake demonstrate the importance of aerosol water for climate modeling studies.
We investigate the vertical distribution, transport characteristics, source contribution and meteorological feedback of dust, biomass burning and fossil fuel combustion aerosols for a unique pollution episode that occurred in late March 2015 in eastern Asia, based on various measurement data and modeling methods. We found that cold front played an important role in the long-range transport of different pollutants and caused a three-layer vertical structure of pollutants over eastern China.
Light-absorbing impurities enhance snowmelt by boosting the absorption of solar energy. It is therefore important for coupled aerosol–climate and ice sheet models to include this effect, and yet most do not. We conduct several thousand simulations and develop a kernel and linear equations relating melt runoff on the Greenland Ice Sheet to the timing and amount of black carbon within precipitation and dry deposition, which can be used to extend the utility of state-of-the-art aerosol models.
Anthropogenic emissions of aerosol particles likely cool the climate system. We investigate the uncertainty in the strength of the cooling effect by exploring the representation of aerosols in a global climate model. We conclude that the specific representation of aerosols in global climate models has important implications for climate modelling. Important factors include the representation of aerosol mixing state, size distribution, and optical properties.
How important for clouds is the ability of biological particles to glaciate droplets at little supercooling? In a case study, the regional atmospheric model COSMO–ART is used. Perturbed and control runs are compared. The number of ice particles that are nucleated by biological particles is highest at around −10 °C. No significant influence on the average state of the cloud ice phase was found. However, the number of ice crystals is slightly enhanced in the absence of other ice nucleators.
Particles in the atmosphere, such as pollution, desert dust, and volcanic ash, have an impact on meteorology. They interact with incoming radiation resulting in a cooling effect of the atmosphere. Today, the use of meteorology and chemistry models help us to understand these processes, but there are a lot of uncertainties. The goal of this work is to evaluate how these interactions are represented in the models by comparing them to satellite data to see how close they are to reality.
We present a new description for the continuous transition of soluble atmospheric particulate from dry to completely dissolved particles. The theoretical development is motivated by observations that suggest particle surfaces begin to dissolve even at very low relative humidities. The results extend the understanding of the potential phase behavior of atmospheric particles with a wide range of implications.
Water uptake can significantly increase the size and therefore alters the optical properties of aerosols. Our model study reveals that the high moisture and aerosol burden in the southern West African monsoon layer makes it favorable to quantify properties that determine the aerosol liquid water content and its impact on the aerosol optical depth and radiative transfer. Especially in moist tropical environments the relative humidity impact on AOD has to be considered in atmospheric models.
Economic loss from disease-induced working time loss reached CNY 398 billion in China 2012. Most is from Eastern and Mid-South China. Mid-South, North, and Eastern China showed most indirect loss. Indirect loss in North, Northwest, and Southwest China is from manufacturing and energy from other regions, while loss in Eastern, Mid-South, and Northeast China is from coal and mining, implying the role of distance in regional links and varied regional loss due to different economic dependencies.
Can semi-volatile organic aerosols lead to fewer cloud particles?
PMCAMx-UF, a 3-D chemical transport model focusing on the simulation of ultrafine particles, has been extended with the addition of the volatility basis set (VBS) approach for the simulation of organic aerosol. The model was applied in Europe and its predictions were evaluated against field observations collected during the PEGASOS 2012 campaign. The condensation of organics led to an increase (50–120 %) in the larger particles but the total number concentration decreased by 10–30 %.
New particle formation involving sulfuric acid, bases and organic compounds is an important source of atmospheric aerosol particles. We investigate the capability of nano-Köhler theory to describe this process by simulating the dynamics of atmospheric molecular clusters. We find that nano-Köhler-type behavior occurs in our simulations when the saturation ratio of the organic vapor and the ratio between organic and inorganic vapor concentrations are in a suitable range.
Atmospheric aerosol particles may undergo liquid–liquid phase separation (LLPS) when exposed to varying relative humidity, with an aqueous organic phase enclosing an aqueous inorganic phase below a threshold of relative humidity. Brown carbon (BrC) compounds will redistribute to the organic phase upon LLPS. We use numerical modeling to study the shortwave radiative impact of LLPS containing BrC and conclude that it is not significant for atmospheric aerosol.
We estimate the uncertainty in an aerosol–climate model that has been tuned to match several common types of observations. We used a large set of model simulations and built emulators so that we could generate 4 million “variants” of our climate model. Even after using nine aerosol and cloud observations to constrain the model, the uncertainty remains large. We conclude that estimates of aerosol forcing from multi-model studies are likely to be more uncertain than currently estimated.
This study evaluates impacts of surface seawater dimethylsulfide on Arctic sulfate aerosol budget, changes in cloud droplet number concentration (CDNC), and cloud radiative forcing under current and future sea ice conditions using an atmospheric global climate model. In the future, sulfate wet removal efficiency is increased by enhanced precipitation, however, simulated aerosol nucleation rates are higher, which result in an overall increase in CDNC and negative cloud radiative forcing.
In this work, we investigated the role of emission reductions on aerosol acidity and particulate nitrate. We found that models exhibit positive biases in pH predictions, attributed to very high levels of crustal elements (Mg, Ca, K) in model simulations, which in turn led to an increasing aerosol pH trend over the past decade and allowed nitrate to become an important component of aerosol, which is inconsistent with the measurements, highlighting the importance of accurate pH prediction.
This study extends our previous investigation in dust–radiation interactions to investigate SRF and its feedbacks on the regional climate and the dust cycle over east Asia by use of the CAM4-BAM. Our results show that SRF increases the east Asian dust emissions significantly by 13.7 % in the spring, in contrast to −7.6 % of decreased dust emissions by DRF. Hence, a significant feature of SRF on the Tibetan Plateau can create a positive feedback loop to enhance the dust cycle over east Asia.
How reliable are CMIP5 models in simulating dust optical depth?
Biases in dust modeling may result in biases in simulating energy budget and regional climate. Output of seven Coupled Model Intercomparison Project Phase 5 (CMIP5) models is examined. Seasonal cycle and spatial pattern of dust optical depth (DOD) in very dusty regions are largely captured by multi-model mean. But observed connections between DOD and local controlling factors such as bareness are not well represented. Future projections by CMIP5 models and a regression model are also analyzed.
Abdalati, W. and Steffen, K.: Greenland Ice Sheet melt extent: 1979–1999, J. Geophys. Res.-Atmos., 106, 33983–33988, https://doi.org/10.1029/2001JD900181, 2001.
AMAP: Snow, Water, Ice and Permafrost. Summary for Policy-makers, Arctic Monitoring and Assessment Programme (AMAP), Oslo, Norway, available at: https://www.amap.no/documents/doc/Snow-Water-Ice-and-Permafrost.-Summary-for-Policy-makers/1532, last access: 27 November 2017.
Anderson, C. H., Dibb, J. E., Griffin, R. J., Hagler, G. S. W., and Bergin, M. H.: Atmospheric water-soluble organic carbon measurements at Summit, Greenland, Atmos. Environ., 42, 5612–5621, https://doi.org/10.1016/j.atmosenv.2008.03.006, 2008.
Antony, R., Mahalinganathan, K., Thamban, M., and Nair, S.: Organic carbon in antarctic snow: Spatial trends and possible sources, Environ. Sci. Technol., 45, 9944–9950, https://doi.org/10.1021/es203512t, 2011.
Aurell, J. and Gullett, B. K.: Emission factors from aerial and ground measurements of field and laboratory forest burns in the southeastern U.S.: PM2.5, black and brown carbon, VOC, and PCDD/PCDF, Environ. Sci. Technol., 47, 8443–8452, https://doi.org/10.1021/es402101k, 2013.
BBC News: “Unusual” Greenland wildfires linked to peat, available at: http://www.bbc.com/news/science-environment-40877099, last access: 6 September 2017.
Bellouin, N. and Haywood, J.: Aerosols: Climatology of Tropospheric Aerosols, 2nd Edn., Elsevier, 2014.
Benscoter, B. W. and Wieder, R. K.: Variability in organic matter lost by combustion in a boreal bog during the 2001 Chisholm fire, Can. J. Forest Res., 33, 2509–2513, https://doi.org/10.1139/x03-162, 2003.
Bond, T. C.: Spectral dependence of visible light absorption by carbonaceous particles emitted from coal combustion, Geophys. Res. Lett., 21, 4075–4078, https://doi.org/10.1029/2001GL013652, 2001.
Buras, R., Dowling, T., and Emde, C.: New secondary-scattering correction in DISORT with increased efficiency for forward scattering, J. Quant. Spectrosc. Ra., 112, 2028–2034, https://doi.org/10.1016/j.jqsrt.2011.03.019, 2011.
Burkhart, J. F., Kylling, A., Schaaf, C. B., Wang, Z., Bogren, W., Storvold, R., Solbø, S., Pedersen, C. A., and Gerland, S.: Unmanned aerial system nadir reflectance and MODIS nadir BRDF-adjusted surface reflectances intercompared over Greenland, The Cryosphere, 11, 1575–1589, https://doi.org/10.5194/tc-11-1575-2017, 2017.
Chavez, P. S.: An improved dark-object subtraction technique for atmospheric scattering correction of multispectral data, Remote Sens. Environ., 24, 459–479, https://doi.org/10.1016/0034-4257(88)90019-3, 1988.
Cofer III, W. R., Levine, J. S., Winstead, E. L., and Stocks, B. J.: New estimates of nitrous oxide emissions from biomass burning, Nature, 349, 689–691, https://doi.org/10.1038/349689a0, 1991.
Conny, J. and Slater, J.: Black carbon and organic carbon in aerosol particles from crown fires in the Canadian boreal forest, J. Geophys. Res., 107, 4116, https://doi.org/10.1029/2001JD001528, 2002.
Daanen, R. P., Ingeman-Nielsen, T., Marchenko, S. S., Romanovsky, V. E., Foged, N., Stendel, M., Christensen, J. H., and Hornbech Svendsen, K.: Permafrost degradation risk zone assessment using simulation models, The Cryosphere, 5, 1043–1056, https://doi.org/10.5194/tc-5-1043-2011, 2011.
Dahlback, A. and Stamnes, K.: A new spherical model for computing the radiation field available for photolysis and heating at twilight, Planet. Space Sci., 39, 671–683, https://doi.org/10.1016/0032-0633(91)90061-E, 1991.
Davies, G. M., Gray, A., Rein, G., and Legg, C. J.: Peat consumption and carbon loss due to smouldering wildfire in a temperate peatland, Forest Ecol. Manag., 308, 169–177, https://doi.org/10.1016/j.foreco.2013.07.051, 2013.
Dibb, J. E., Arsenault, M., Peterson, M. C., and Honrath, R. E.: Fast nitrogen oxide photochemistry in Summit, Greenland snow, Atmos. Environ., 36, 2501–2511, https://doi.org/10.1016/S1352-2310(02)00130-9, 2002.
Drysdale, D.: An Introduction to Fire Dynamics, 3rd Edn., John Wiley & Sons, Ltd., 2011.
Emde, C., Buras-Schnell, R., Kylling, A., Mayer, B., Gasteiger, J., Hamann, U., Kylling, J., Richter, B., Pause, C., Dowling, T., and Bugliaro, L.: The libRadtran software package for radiative transfer calculations (version 2.0.1), Geosci. Model Dev., 9, 1647–1672, https://doi.org/10.5194/gmd-9-1647-2016, 2016.
Escuin, S., Navarro, R., and Fernández, P.: Fire severity assessment by using NBR (Normalized Burn Ratio) and NDVI (Normalized Difference Vegetation Index) derived from LANDSAT TM/ETM images, Int. J. Remote Sens., 29, 1053–1073, https://doi.org/10.1080/01431160701281072, 2008.
Evangeliou, N., Balkanski, Y., Cozic, A., Hao, W. M., and Møller, A. P.: Wildfires in Chernobyl-contaminated forests and risks to the population and the environment: A new nuclear disaster about to happen?, Environ. Int., 73, 346–358, https://doi.org/10.1016/j.envint.2014.08.012, 2014.
Evangeliou, N., Balkanski, Y., Cozic, A., Hao, W. M., Mouillot, F., Thonicke, K., Paugam, R., Zibtsev, S., Mousseau, T. A., Wang, R., Poulter, B., Petkov, A., Yue, C., Cadule, P., Koffi, B., Kaiser, J. W., Møller, A. P., and Classen, A. T.: Fire evolution in the radioactive forests of Ukraine and Belarus: Future risks for the population and the environment, Ecol. Monogr., 85, 49–72, https://doi.org/10.1890/14-1227.1, 2015.
Evangeliou, N., Zibtsev, S., Myroniuk, V., Zhurba, M., Hamburger, T., Stohl, A., Balkanski, Y., Paugam, R., Mousseau, T. A., Møller, A. P., and Kireev, S. I.: Resuspension and atmospheric transport of radionuclides due to wildfires near the Chernobyl Nuclear Power Plant in 2015: An impact assessment., Sci. Rep.-UK, 6, 26062, https://doi.org/10.1038/srep26062, 2016.
Fang, X., Thompson, R. L., Saito, T., Yokouchi, Y., Kim, J., Li, S., Kim, K. R., Park, S., Graziosi, F., and Stohl, A.: Sulfur hexafluoride (SF6) emissions in East Asia determined by inverse modeling, Atmos. Chem. Phys., 14, 4779–4791, https://doi.org/10.5194/acp-14-4779-2014, 2014.
Feng, Y., Ramanathan, V., and Kotamarthi, V. R.: Brown carbon: a significant atmospheric absorber of solar radiation?, Atmos. Chem. Phys., 13, 8607–8621, https://doi.org/10.5194/acp-13-8607-2013, 2013.
Ferguson, S. A., Collins, R. L., Ruthford, J., and Fukuda, M.: Vertical distribution of nighttime smoke following a wildland biomass fire in boreal Alaska, J. Geophys. Res., 108, 4743, https://doi.org/10.1029/2002JD003324, https://doi.org/10.1029/2002JD003324, 2003.
Fernandez Anez, N., Garcia Torrent, J., Medic Pejic, L. and Grima Olmedo, C.: Detection of incipient self-ignition process in solid fuels through gas emissions methodology, J. Loss Prevent. Proc., 36, 343–351, https://doi.org/10.1016/j.jlp.2015.02.010, 2015.
Flanner, M. G., Zender, C. S., Randerson, J. T., and Rasch, P. J.: Present-day climate forcing and response from black carbon in snow, J. Geophys. Res.-Atmos., 112, 1–17, https://doi.org/10.1029/2006JD008003, 2007.
Flanner, M. G., Zender, C. S., Hess, P. G., Mahowald, N. M., Painter, T. H., Ramanathan, V., and Rasch, P. J.: Springtime warming and reduced snow cover from carbonaceous particles, Atmos. Chem. Phys., 9, 2481–2497, https://doi.org/10.5194/acp-9-2481-2009, 2009.
Forster, C., Wandinger, U., Wotawa, G., James, P., Mattis, I., Althausen, D., Simmonds, P., O'Doherty, S., Jennings, S. G., Kleefeld, C., Schneider, J., Trickl, T., Kreipl, S., Jäger, H., and Stohl, A.: Transport of boreal forest fire emissions from Canada to Europe, J. Geophys. Res., 106, 22887, https://doi.org/10.1029/2001JD900115, 2001.
Forster, C., Stohl, A., and Seibert, P.: Parameterization of convective transport in a Lagrangian particle dispersion model and its evaluation, J. Appl. Meteorol. Clim., 46, 403–422, https://doi.org/10.1175/JAM2470.1, 2007.
Freitas, S. R., Longo, K. M., Chatfield, R., Latham, D., Silva Dias, M. A. F., Andreae, M. O., Prins, E., Santos, J. C., Gielow, R., and Carvalho Jr., J. A.: Including the sub-grid scale plume rise of vegetation fires in low resolution atmospheric transport models, Atmos. Chem. Phys., 7, 3385–3398, https://doi.org/10.5194/acp-7-3385-2007, 2007.
Freitas, S. R., Longo, K. M., Trentmann, J., and Latham, D.: Technical Note: Sensitivity of 1-D smoke plume rise models to the inclusion of environmental wind drag, Atmos. Chem. Phys., 10, 585–594, https://doi.org/10.5194/acp-10-585-2010, 2010.
French, N., Kasischke, E., Hall, R., Murphy, K., Verbyla, D., Hoy, E., and Allen, J.: Using Landsat data to assess fire and burn severity in the North American boreal forest region: an overview and summary of results, Int. J. Wildland Fire, 17, 443–462, https://doi.org/10.1071/WF08007, 2008.
Fromm, M., Bevilacqua, R., Servranckx, R., Rosen, J., Thayer, J. P., Herman, J., and Larko, D.: Pyro-cumulonimbus injection of smoke to the stratosphere: Observations and impact of a super blowup in northwestern Canada on 3–4 August 1998, J. Geophys. Res.-Atmos., 110, 1–17, https://doi.org/10.1029/2004JD005350, 2005.
Grannas, A. M., Shepson, P. B., and Filley, T. R.: Photochemistry and nature of organic matter in Arctic and Antarctic snow, Global Biogeochem. Cy., 18, GB1006, https://doi.org/10.1029/2003GB002133, 2004.
Grythe, H., Kristiansen, N. I., Groot Zwaaftink, C. D., Eckhardt, S., Ström, J., Tunved, P., Krejci, R., and Stohl, A.: A new aerosol wet removal scheme for the Lagrangian particle model FLEXPART v10, Geosci. Model Dev., 10, 1447–1466, https://doi.org/10.5194/gmd-10-1447-2017, 2017.
Hansen, J. and Nazarenko, L.: Soot climate forcing via snow and ice albedos, P. Natl. Acad. Sci. USA, 101, 423–428, https://doi.org/10.1073/pnas.2237157100, 2004.
Hansen, J., Sato, M., Ruedy, R., Nazarenko, L., Lacis, A., Schmidt, G. A., Russell, G., Aleinov, I., Bauer, M., Bauer, S., Bell, N., Cairns, B., Canuto, V., Chandler, M., Cheng, Y., Del Genio, A., Faluvegi, G., Fleming, E., Friend, A., Hall, T., Jackman, C., Kelley, M., Kiang, N., Koch, D., Lean, J., Lerner, J., Lo, K., Menon, S., Miller, R., Minnis, P., Novakov, T., Oinas, V., Perlwitz, J., Perlwitz, J., Rind, D., Romanou, A., Shindell, D., Stone, P., Sun, S., Tausnev, N., Thresher, D., Wielicki, B., Wong, T., Yao, M., and Zhang, S.: Efficacy of climate forcings, J. Geophys. Res.-Atmos., 110, 1–45, https://doi.org/10.1029/2005JD005776, 2005.
Hao, W. M. and Ward, D. E.: Methane production from global biomass burning, J. Geophys. Res.-Atmos., 98, 20657–20661, https://doi.org/10.1029/93JD01908, 1993.
Hao, W. M., Petkov, A., Nordgren, B. L., Corley, R. E., Silverstein, R. P., Urbanski, S. P., Evangeliou, N., Balkanski, Y., and Kinder, B. L.: Daily black carbon emissions from fires in northern Eurasia for 2002–2015, Geosci. Model Dev., 9, 4461–4474, https://doi.org/10.5194/gmd-9-4461-2016, 2016.
Holben, B. N.: Characteristics of maximum-value composite images from temporal AVHRR data, Int. J. Remote Sens., 7, 1417–1434, https://doi.org/10.1080/01431168608948945, 1986.
Holben, B. N., Eck, T. F., Slutsker, I., Tanré, D., Buis, J. P., Setzer, A., Vermote, E., Reagan, J. A., Kaufman, Y. J., Nakajima, T., Lavenu, F., Jankowiak, I., and Smirnov, A.: AERONET – A Federated Instrument Network and Data Archive for Aerosol Characterization, Remote Sens. Environ., 66, 1–16, https://doi.org/10.1016/S0034-4257(98)00031-5, 1998.
Hosseini, S., Li, Q., Cocker, D., Weise, D., Miller, A., Shrivastava, M., Miller, J. W., Mahalingam, S., Princevac, M., and Jung, H.: Particle size distributions from laboratory-scale biomass fires using fast response instruments, Atmos. Chem. Phys., 10, 8065–8076, https://doi.org/10.5194/acp-10-8065-2010, 2010.
Hu, Y., Fernandez-Anez, N., Smith, T. E. L., and Rein, G.: Review of emissions from smouldering peat fires and their contribution to regional haze episodes, Int. J. Wildland Fire, 27, 293–312, https://doi.org/10.1071/WF17084, 2018.
IPCC: Climate Change 2013: The Physical Science Basis. Contribution to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Stocker, T. F., Qin, D., Plattner, G.-K., Tignor, M. M. B., Allen, S. K., Boschung, J., Nauels, A., Xia, Y., Bex, V., and Midgley, P. M., Cambridge University Press, 2013.
Jacobson, M. Z.: Strong radiative heating due to the mixing state of black carbon in atmospheric aerosols, Nature, 409, 695–697, https://doi.org/10.1038/35055518, 2001.
Jedrzejek, B., Drees, B., Daniëls, F. J. A., and Hölzel, N.: Vegetation pattern of mountains in West Greenland – a baseline for long-term surveillance of global warming impacts, Plant Ecol. Divers., 6, 405–422, https://doi.org/10.1080/17550874.2013.802049, 2013.
Jo, D. S., Park, R. J., Lee, S., Kim, S.-W., and Zhang, X.: A global simulation of brown carbon: implications for photochemistry and direct radiative effect, Atmos. Chem. Phys., 16, 3413–3432, https://doi.org/10.5194/acp-16-3413-2016, 2016.
Justice, C. O., Giglio, L., Korontzi, S., Owens, J., Morisette, J. T., Roy, D., Descloitres, J., Alleaume, S., Petitcolin, F., and Kaufman, Y.: The MODIS fire products, Remote Sens. Environ., 83, 244–262, https://doi.org/10.1016/S0034-4257(02)00076-7, 2002.
Kato, S., Ackerman, T. P., Mather, J. H., and Clothiaux, E. E.: The k-distribution method and correlated-k approximation for a shortwave radiative transfer model, J. Quant. Spectrosc. Ra., 62, 109–121, https://doi.org/10.1016/S0022-4073(98)00075-2, 1999.
Keegan, K. M., Albert, M. R., Mcconnell, J. R., and Baker, I.: Climate change and forest fires synergistically drive widespread melt events of the Greenland Ice Sheet, P. Natl. Acad. Sci. USA, 111, 7964–7967, https://doi.org/10.1073/pnas.1405397111, 2014.
Key, C. H. and Benson, N. C.: Landscape assessment: Sampling and analysis methods, USDA For. Serv. Gen. Tech. Rep. RMRS-GTR-164-CD, June, 1–55, https://doi.org/10.1002/app.1994.070541203, 2006.
Klimont, Z., Kupiainen, K., Heyes, C., Purohit, P., Cofala, J., Rafaj, P., Borken-Kleefeld, J., and Schöpp, W.: Global anthropogenic emissions of particulate matter including black carbon, Atmos. Chem. Phys., 17, 8681–8723, https://doi.org/10.5194/acp-17-8681-2017, 2017.
Lavoie, C. and Pellerin, S.: Fires in temperate peatlands (southern Quebec): past and recent trends, Can. J. Botany, 85, 263–272, https://doi.org/10.1139/B07-012, 2007.
Legrand, M., Preunkert, S., Jourdain, B., Guilhermet, J., Faïn, X., Alekhina, I., and Petit, J. R.: Water-soluble organic carbon in snow and ice deposited at Alpine, Greenland, and Antarctic sites: a critical review of available data and their atmospheric relevance, Clim. Past, 9, 2195–2211, https://doi.org/10.5194/cp-9-2195-2013, 2013.
Legrand, M., McConnell, J., Fischer, H., Wolff, E. W., Preunkert, S., Arienzo, M., Chellman, N., Leuenberger, D., Maselli, O., Place, P., Sigl, M., Schüpbach, S., and Flannigan, M.: Boreal fire records in Northern Hemisphere ice cores: a review, Clim. Past, 12, 2033–2059, https://doi.org/10.5194/cp-12-2033-2016, 2016.
Leino, K., Riuttanen, L., Nieminen, T., Väänänen, R., Pohja, T., Keronen, P., Järvi, L., Aalto, P. P., Virkkula, A., Kerminen, V. M., Petäjä, T., Kulmala, M., Nieminen, T., Dal Maso, M., and Virkkula, A.: Biomass-burning smoke episodes in Finland from eastern European wildfires, Boreal Environ. Res., 19, 275–292, 2014.
Lelieveld, J., Evans, J. S., Fnais, M., Giannadaki, D., and Pozzer, A.: The contribution of outdoor air pollution sources to premature mortality on a global scale, Nature, 525, 367–371, https://doi.org/10.1038/nature15371, 2015.
Leung, F. Y. T., Logan, J. A., Park, R., Hyer, E., Kasischke, E., Streets, D., and Yurganov, L.: Impacts of enhanced biomass burning in the boreal forests in 1998 on tropospheric chemistry and the sensitivity of model results to the injection height of emissions, J. Geophys. Res.-Atmos., 112, 1–15, https://doi.org/10.1029/2006JD008132, 2007.
Lim, H. J., Turpin, B. J., Russell, L. M., and Bates, T. S.: Organic and elemental carbon measurements during ACE-Asia suggest a longer atmospheric lifetime for elemental carbon, Environ. Sci. Technol., 37, 3055–3061, https://doi.org/10.1021/es020988s, 2003.
Limbeck, A., Kulmala, M., and Puxbaum, H.: Secondary organic aerosol formation in the atmosphere via heterogeneous reaction of gaseous isoprene on acidic particles, Geophys. Res. Lett., 30, 4–7, https://doi.org/10.1029/2003GL017738, 2003.
Long, C. M., Nascarella, M. A., and Valberg, P. A.: Carbon black vs. black carbon and other airborne materials containing elemental carbon: Physical and chemical distinctions, Environ. Pollut., 181, 271–286, https://doi.org/10.1016/j.envpol.2013.06.009, 2013.
Lyons, W. B., Welch, K. A., and Doggett, J. K.: Organic carbon in Antarctic snow, Geophys. Res. Lett., 34, 2–5, https://doi.org/10.1029/2006GL028150, 2007.
Magnan, G., Lavoie, M., and Payette, S.: Impact of fire on long-term vegetation dynamics of ombrotrophic peatlands in northwestern Québec, Canada, Quaternary Res., 77, 110–121, https://doi.org/10.1016/j.yqres.2011.10.006, 2012.
Massling, A., Nielsen, I. E., Kristensen, D., Christensen, J. H., Sørensen, L. L., Jensen, B., Nguyen, Q. T., Nøjgaard, J. K., Glasius, M., and Skov, H.: Atmospheric black carbon and sulfate concentrations in Northeast Greenland, Atmos. Chem. Phys., 15, 9681–9692, https://doi.org/10.5194/acp-15-9681-2015, 2015.
Mukai, H. and Ambe, Y.: Characterization of a humic acid-like brown substance in airborne particulate matter and tentative identification of its origin, Atmos. Environ., 20, 813–819, https://doi.org/10.1016/0004-6981(86)90265-9, 1986.
Myhre, G., Shindell, D., Bréon, F.-M., Collins, W., Fuglestvedt, J., Huang, J., Koch, D., Lamarque, J.-F., Lee, D., Mendoza, B., Nakajima, T., Robock, A., Stephens, G., Takemura, T., and Zhang, H.: Anthropogenic and Natural Radiative Forcing, in Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Stocker, T. F., Qin, D., Plattner, G.-K., Tignor, M., Allen, S. K., Boschung, J., Nauels, A., Xia, Y., Bex, V., and Midgley, P. M., Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 659–740, 2013.
NASA: FIRMS. Web Fire Mapper, available at: https://firms.modaps.eosdis.nasa.gov/firemap/, last access: 5 September 2017a.
NASA: Roundtable: The Greenland Wildfire, available at: https://earthobservatory.nasa.gov/blogs/earthmatters/2017/08/10/roundtable-the-greenland-wildfire/, last access: 6 September 2017b.
NASA: Wildfires Continue to Beleaguer Western Canada, available at: https://www.nasa.gov/image-feature/goddard/2017/wildfires-continue-to-beleaguer-western-canada, last access: 29 October 2017c.
New Scientist Magazine: Largest ever wildfire in Greenland seen burning from space, available at: https://www.newscientist.com/article/2143159-largest-ever-wildfire-in-greenland-seen-burning-from-space/, last access: 6 September 2017.
Page, S. E., Siegert, F., Rieley, J. O., Boehm, H.-D. V., Jada, A., and Limin, S.: The amount of carbon released from peat and forest fires in Indonesia during 1997, Nature, 420, 61–65, https://doi.org/10.1038/nature01131, 2015.
Paugam, R., Wooster, M., Atherton, J., Freitas, S. R., Schultz, M. G., and Kaiser, J. W.: Development and optimization of a wildfire plume rise model based on remote sensing data inputs – Part 2, Atmos. Chem. Phys. Discuss., 15, 9815–9895, https://doi.org/10.5194/acpd-15-9815-2015, 2015.
Pisso, I., Sollum, E., Grythe, H., Kristiansen, N., Cassiani, M., Eckhardt, S., Arnold, D., Morton, D., Thompson, R. L., Groot Zwaaftink, C. D., Evangeliou, N., Sodemann, H., Haimberger, L., Henne, S., Brunner, D., Burkhart, J. F., Fouilloux, A., Brioude, J., Philipp, A., Seibert, P., and Stohl, A.: The Lagrangian particle dispersion model FLEXPART version 10.3, Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2018-333, in review, 2019.
Pokhrel, R. P., Wagner, N. L., Langridge, J. M., Lack, D. A., Jayarathne, T., Stone, E. A., Stockwell, C. E., Yokelson, R. J., and Murphy, S. M.: Parameterization of single-scattering albedo (SSA) and absorption Ångström exponent (AAE) with EC∕OC for aerosol emissions from biomass burning, Atmos. Chem. Phys., 16, 9549–9561, https://doi.org/10.5194/acp-16-9549-2016, 2016.
Polashenski, C. M., Dibb, J. E., Flanner, M. G., Chen, J. Y., Courville, Z. R., Lai, A. M., Schauer, J. J., Shafer, M. M., and Bergin, M.: Neither dust nor black carbon causing apparent albedo decline in Greenland's dry snow zone: Implications for MODIS C5 surface reflectance, Geophys. Res. Lett., 42, 9319–9327, https://doi.org/10.1002/2015GL065912, 2015.
Randerson, J. T., Chen, Y., Van Der Werf, G. R., Rogers, B. M., and Morton, D. C.: Global burned area and biomass burning emissions from small fires, J. Geophys. Res.-Biogeo., 117, G04012, https://doi.org/10.1029/2012JG002128, 2012.
Reddy, A. D., Hawbaker, T. J., Wurster, F., Zhu, Z., Ward, S., Newcomb, D., and Murray, R.: Quantifying soil carbon loss and uncertainty from a peatland wildfire using multi-temporal LiDAR, Remote Sens. Environ., 170, 306–316, https://doi.org/10.1016/j.rse.2015.09.017, 2015.
Rémy, S., Veira, A., Paugam, R., Sofiev, M., Kaiser, J. W., Marenco, F., Burton, S. P., Benedetti, A., Engelen, R. J., Ferrare, R., and Hair, J. W.: Two global data sets of daily fire emission injection heights since 2003, Atmos. Chem. Phys., 17, 2921–2942, https://doi.org/10.5194/acp-17-2921-2017, 2017.
Restuccia, F., Ptak, N., and Rein, G.: Self-heating behavior and ignition of shale rock, Combust. Flame, 176, 213–219, https://doi.org/10.1016/j.combustflame.2016.09.025, 2017a.
Restuccia, F., Huang, X., and Rein, G.: Self-ignition of natural fuels: Can wildfires of carbon-rich soil start by self-heating?, Fire Safety J., 91, 828–834, https://doi.org/10.1016/j.firesaf.2017.03.052, 2017b.
Seiler, W. and Crutzen, P. J.: Estimates of gross and net fluxes of carbon between the biosphere and the atmosphere from biomass burning, Climatic Change, 2, 207–247, https://doi.org/10.1007/BF00137988, 1980.
SERMITSIAQ: Se billeder: Naturbrand udvikler kraftig røg, available at: http://sermitsiaq.ag/se-billeder-naturbrand-udvikler-kraftig-roeg, last Access: 6 September 2017 (in Danish).
Shetler, G., Turetsky, M. R., Kane, E., and Kasischke, E.: Sphagnum mosses limit total carbon consumption during fire in Alaskan black spruce forests, Can. J. Forest Res., 38, 2328–2336, https://doi.org/10.1139/X08-057, 2008.
Shi, Y., Matsunaga, T., Saito, M., Yamaguchi, Y., and Chen, X.: Comparison of global inventories of CO2 emissions from biomass burning during 2002–2011 derived from multiple satellite products, Environ. Pollut., 206, 479–487, https://doi.org/10.1016/j.envpol.2015.08.009, 2015.
Skeie, R. B., Berntsen, T., Myhre, G., Pedersen, C. A., Ström, J., Gerland, S., and Ogren, J. A.: Black carbon in the atmosphere and snow, from pre-industrial times until present, Atmos. Chem. Phys., 11, 6809–6836, https://doi.org/10.5194/acp-11-6809-2011, 2011.
Smirnov, N. S., Korotkov, V. N., and Romanovskaya, A. A.: Black carbon emissions from wildfires on forest lands of the Russian Federation in 2007–2012, Russ. Meteorol. Hydro+., 40, 435–442, https://doi.org/10.3103/S1068373915070018, 2015.
Stamnes, K., Tsay, S.-C., Wiscombe, W., and Jayaweera, K.: Numerically stable algorithm for discrete-ordinate-method radiative transfer in multiple scattering and emitting layered media, Appl. Optics, 27, 2502, https://doi.org/10.1364/AO.27.002502, 1988.
Stendel, M., Christensen, J. H., and Petersen, D.: Arctic Climate and Climate Change with a Focus on Greenland, Adv. Ecol. Res., 40, 13–43, https://doi.org/10.1016/S0065-2504(07)00002-5, 2008.
Stohl, A., Andrews, E., Burkhart, J. F., Forster, C., Herber, A., Hoch, S. W., Kowal, D., Lunder, C., Mefford, T., Ogren, J. A., Sharma, S., Spichtinger, N., Stebel, K., Stone, R., Ström, J., Tørseth, K., Wehrli, C., and Yttri, K. E.: Pan-Arctic enhancements of light absorbing aerosol concentrations due to North American boreal forest fires during summer 2004, J. Geophys. Res.-Atmos., 111, 1–20, https://doi.org/10.1029/2006JD007216, 2006.
Stohl, A., Berg, T., Burkhart, J. F., Fjǽraa, A. M., Forster, C., Herber, A., Hov, Ø., Lunder, C., McMillan, W. W., Oltmans, S., Shiobara, M., Simpson, D., Solberg, S., Stebel, K., Ström, J., Tørseth, K., Treffeisen, R., Virkkunen, K., and Yttri, K. E.: Arctic smoke – record high air pollution levels in the European Arctic due to agricultural fires in Eastern Europe in spring 2006, Atmos. Chem. Phys., 7, 511–534, https://doi.org/10.5194/acp-7-511-2007, 2007.
Stohl, A., Prata, A. J., Eckhardt, S., Clarisse, L., Durant, A., Henne, S., Kristiansen, N. I., Minikin, A., Schumann, U., Seibert, P., Stebel, K., Thomas, H. E., Thorsteinsson, T., Tørseth, K., and Weinzierl, B.: Determination of time- and height-resolved volcanic ash emissions and their use for quantitative ash dispersion modeling: the 2010 Eyjafjallajökull eruption, Atmos. Chem. Phys., 11, 4333–4351, https://doi.org/10.5194/acp-11-4333-2011, 2011.
Stohl, A., Klimont, Z., Eckhardt, S., Kupiainen, K., Shevchenko, V. P., Kopeikin, V. M., and Novigatsky, A. N.: Black carbon in the Arctic: the underestimated role of gas flaring and residential combustion emissions, Atmos. Chem. Phys., 13, 8833–8855, https://doi.org/10.5194/acp-13-8833-2013, 2013.
Stroeve, J., Box, J. E., Gao, F., Liang, S., Nolin, A., and Schaaf, C.: Accuracy assessment of the MODIS 16-day albedo product for snow: Comparisons with Greenland in situ measurements, Remote Sens. Environ., 94, 46–60, https://doi.org/10.1016/j.rse.2004.09.001, 2005.
Sunderman, S. O. and Weisberg, P. J.: Remote sensing approaches for reconstructing fire perimeters and burn severity mosaics in desert spring ecosystems, Remote Sens. Environ., 115, 2384–2389, https://doi.org/10.1016/j.rse.2011.05.001, 2011.
Turetsky, M. R., Donahue, W. F.m and Benscoter, B. W.: Experimental drying intensifies burning and carbon losses in a northern peatland, Nat. Commun., 2, 514, https://doi.org/10.1038/ncomms1523, 2011.
Turetsky, M. R., Benscoter, B., Page, S., Rein, G., van der Werf, G. R., and Watts, A.: Global vulnerability of peatlands to fire and carbon loss, Nat. Geosci., 8, 11–14, https://doi.org/10.1038/ngeo2325, 2014.
von Schneidemesser, E., Schauer, J. J., Hagler, G. S. W., and Bergin, M. H.: Concentrations and sources of carbonaceous aerosol in the atmosphere of Summit, Greenland, Atmos. Environ., 43, 4155–4162, https://doi.org/10.1016/j.atmosenv.2009.05.043, 2009.
Wandji Nyamsi, W., Arola, A., Blanc, P., Lindfors, A. V., Cesnulyte, V., Pitkänen, M. R. A., and Wald, L.: Technical Note: A novel parameterization of the transmissivity due to ozone absorption in the k-distribution method and correlated-k approximation of Kato et al. (1999) over the UV band, Atmos. Chem. Phys., 15, 7449–7456, https://doi.org/10.5194/acp-15-7449-2015, 2015.
Warren, S. G.: Can black carbon in snow be detected by remote sensing?, J. Geophys. Res.-Atmos., 118, 779–786, https://doi.org/10.1029/2012JD018476, 2013.
Wieder, R. K., Scott, K. D., Kamminga, K., Vile, M. A., Vitt, D. H., Bone, T., Xu, B., Benscoter, B. W., and Bhatti, J. S.: Postfire carbon balance in boreal bogs of Alberta, Canada, Glob. Change Biol., 15, 63–81, https://doi.org/10.1111/j.1365-2486.2008.01756.x, 2009.
Winiger, P., Andersson, A., Eckhardt, S., Stohl, A., Semiletov, I. P., Dudarev, O. V., Charkin, A., Shakhova, N., Klimont, Z., Heyes, C., and Gustafsson, Ö.: Siberian Arctic black carbon sources constrained by model and observation, P. Natl. Acad. Sci. USA, 114, E1054–E1061, https://doi.org/10.1073/pnas.1613401114, 2017.
Winker, D. M., Vaughan, M. A., Omar, A., Hu, Y., Powell, K. A., Liu, Z., Hunt, W. H., and Young, S. A.: Overview of the CALIPSO mission and CALIOP data processing algorithms, J. Atmos. Ocean. Tech., 26, 2310–2323, https://doi.org/10.1175/2009JTECHA1281.1, 2009.
Wu, D., Huang, X., Norman, F., Verplaetsen, F., Berghmans, J., and Van Den Bulck, E.: Experimental investigation on the self-ignition behaviour of coal dust accumulations in oxy-fuel combustion system, Fuel, 160, 245–254, https://doi.org/10.1016/j.fuel.2015.07.050, 2015.
Wu, G. M., Cong, Z. Y., Kang, S. C., Kawamura, K., Fu, P. Q., Zhang, Y. L., Wan, X., Gao, S. P., and Liu, B.: Brown carbon in the cryosphere: Current knowledge and perspective, Adv. Clim. Chang. Res., 7, 82–89, https://doi.org/10.1016/j.accre.2016.06.002, 2016.
Zhuravleva, T. B., Kabanov, D. M., Nasrtdinov, I. M., Russkova, T. V., Sakerin, S. M., Smirnov, A., and Holben, B. N.: Radiative characteristics of aerosol during extreme fire event over Siberia in summer 2012, Atmos. Meas. Tech., 10, 179–198, https://doi.org/10.5194/amt-10-179-2017, 2017.

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