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  • 1. Aas, W.
    et al.
    Tsyro, S.
    Bieber, E.
    Bergström, Robert
    SMHI, Forskningsavdelningen, Luftmiljö.
    Ceburnis, D.
    Ellermann, T.
    Fagerli, H.
    Froelich, M.
    Gehrig, R.
    Makkonen, U.
    Nemitz, E.
    Otjes, R.
    Perez, N.
    Perrino, C.
    Prevot, A. S. H.
    Putaud, J. -P
    Simpson, D.
    Spindler, G.
    Vana, M.
    Yttri, K. E.
    Lessons learnt from the first EMEP intensive measurement periods2012Inngår i: Atmospheric Chemistry And Physics, ISSN 1680-7316, E-ISSN 1680-7324, Vol. 12, nr 17, s. 8073-8094Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The first EMEP intensive measurement periods were held in June 2006 and January 2007. The measurements aimed to characterize the aerosol chemical compositions, including the gas/aerosol partitioning of inorganic compounds. The measurement program during these periods included daily or hourly measurements of the secondary inorganic components, with additional measurements of elemental- and organic carbon (EC and OC) and mineral dust in PM1, PM2.5 and PM10. These measurements have provided extended knowledge regarding the composition of particulate matter and the temporal and spatial variability of PM, as well as an extended database for the assessment of chemical transport models. This paper summarise the first experiences of making use of measurements from the first EMEP intensive measurement periods along with EMEP model results from the updated model version to characterise aerosol composition. We investigated how the PM chemical composition varies between the summer and the winter month and geographically. The observation and model data are in general agreement regarding the main features of PM10 and PM2.5 composition and the relative contribution of different components, though the EMEP model tends to give slightly lower estimates of PM10 and PM2.5 compared to measurements. The intensive measurement data has identified areas where improvements are needed. Hourly concurrent measurements of gaseous and particulate components for the first time facilitated testing of modelled diurnal variability of the gas/aerosol partitioning of nitrogen species. In general, the modelled diurnal cycles of nitrate and ammonium aerosols are in fair agreement with the measurements, but the diurnal variability of ammonia is not well captured. The largest differences between model and observations of aerosol mass are seen in Italy during winter, which to a large extent may be explained by an underestimation of residential wood burning sources. It should be noted that both primary and secondary OC has been included in the calculations for the first time, showing promising results. Mineral dust is important, especially in southern Europe, and the model seems to capture the dust episodes well. The lack of measurements of mineral dust hampers the possibility for model evaluation for this highly uncertain PM component. There are also lessons learnt regarding improved measurements for future intensive periods. There is a need for increased comparability between the measurements at different sites. For the nitrogen compounds it is clear that more measurements using artefact free methods based on continuous measurement methods and/or denuders are needed. For EC/OC, a reference methodology (both in field and laboratory) was lacking during these periods giving problems with comparability, though measurement protocols have recently been established and these should be followed by the Parties to the EMEP Protocol. For measurements with no defined protocols, it might be a good solution to use centralised laboratories to ensure comparability across the network. To cope with the introduction of these new measurements, new reporting guidelines have been developed to ensure that all proper information about the methodologies and data quality is given.

    Fulltekst (pdf)
    fulltext
  • 2.
    Amorim, Jorge Humberto
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Asker, Christian
    SMHI, Forskningsavdelningen, Luftmiljö.
    Belusic, Danijel
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Carvalho, Ana
    SMHI, Forskningsavdelningen, Luftmiljö.
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    Gidhagen, Lars
    SMHI, Forskningsavdelningen, Luftmiljö.
    Hundecha, Yeshewatesfa
    SMHI, Forskningsavdelningen, Hydrologi.
    Körnich, Heiner
    SMHI, Forskningsavdelningen, Meteorologi.
    Lind, Petter
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Olsson, Esbjörn
    SMHI, Forskningsavdelningen, Meteorologi.
    Olsson, Jonas
    SMHI, Forskningsavdelningen, Hydrologi.
    Segersson, David
    SMHI, Forskningsavdelningen, Luftmiljö.
    Strombäck, Lena
    SMHI, Forskningsavdelningen, Hydrologi.
    Joe, Paul
    Baklanov, Alexander
    Integrated Urban Services for European cities: the Stockholm case2018Inngår i: WMO Bulletin, ISSN 0042-9767, Vol. 67, nr 2, s. 33-40Artikkel i tidsskrift (Fagfellevurdert)
    Fulltekst (pdf)
    fulltext
  • 3.
    Amorim, Jorge Humberto
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Engardt, Magnuz
    Johansson, Christer
    Ribeiro, Isabel
    SMHI, Forskningsavdelningen, Luftmiljö.
    Sannebro, Magnus
    Regulating and Cultural Ecosystem Services of Urban Green Infrastructure in the Nordic Countries: A Systematic Review2021Inngår i: International Journal of Environmental Research and Public Health, ISSN 1661-7827, E-ISSN 1660-4601, Vol. 18, nr 3, artikkel-id 1219Artikkel i tidsskrift (Fagfellevurdert)
    Fulltekst (pdf)
    fulltext
  • 4.
    Amorim, Jorge Humberto
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Valente, J.
    Cascao, P.
    Ribeiro, L. M.
    Viegas, D. X.
    Ottmar, R.
    Miranda, A. I.
    Near-source grid-based measurement of CO and PM2.5 concentration during a full-scale fire experiment in southern European shrubland2016Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 145, s. 19-28Artikkel i tidsskrift (Fagfellevurdert)
  • 5.
    Andersson, Camilla
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Bergström, Robert
    SMHI, Forskningsavdelningen, Luftmiljö.
    Bennet, Cecilia
    SMHI, Forskningsavdelningen, Luftmiljö.
    Robertson, Lennart
    SMHI, Forskningsavdelningen, Luftmiljö.
    Thomas, Manu
    SMHI, Forskningsavdelningen, Luftmiljö.
    Korhonen, H.
    Lehtinen, K. E. J.
    Kokkola, H.
    MATCH-SALSA - Multi-scale Atmospheric Transport and CHemistry model coupled to the SALSA aerosol microphysics model - Part 1: Model description and evaluation2015Inngår i: Geoscientific Model Development, ISSN 1991-959X, E-ISSN 1991-9603, Vol. 8, nr 2, s. 171-189Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We have implemented the sectional aerosol dynamics model SALSA (Sectional Aerosol module for Large Scale Applications) in the European-scale chemistry-transport model MATCH (Multi-scale Atmospheric Transport and Chemistry). The new model is called MATCH-SALSA. It includes aerosol microphysics, with several formulations for nucleation, wet scavenging and condensation. The model reproduces observed higher particle number concentration (PNC) in central Europe and lower concentrations in remote regions. The modeled PNC size distribution peak occurs at the same or smaller particle size as the observed peak at four measurement sites spread across Europe. Total PNC is underestimated at northern and central European sites and accumulation-mode PNC is underestimated at all investigated sites. The low nucleation rate coefficient used in this study is an important reason for the underestimation. On the other hand, the model performs well for particle mass (including secondary inorganic aerosol components), while elemental and organic carbon concentrations are underestimated at many of the sites. Further development is needed, primarily for treatment of secondary organic aerosol, in terms of biogenic emissions and chemical transformation. Updating the biogenic secondary organic aerosol (SOA) scheme will likely have a large impact on modeled PM2.5 and also affect the model performance for PNC through impacts on nucleation and condensation.

    Fulltekst (pdf)
    fulltext
  • 6.
    Andersson, Camilla
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Bergström, Robert
    SMHI, Forskningsavdelningen, Luftmiljö.
    Johansson, Christer
    Population exposure and mortality due to regional background PM in Europe - Long-term simulations of source region and shipping contributions2009Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 43, nr 22-23, s. 3614-3620Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents the contribution to population exposure (PE) of regional background fine primary (PPM(2.5)) and secondary inorganic (SIA) particulate matter and its impact on mortality in Europe during 1997-2003 calculated with a chemistry transport model. Contributions to concentrations and PE due to emissions from shipping, Western (WEU), Eastern (EEU), and Northern Europe are compared. WEU contributes about 40% to both PPM(2.5) and SIA concentrations, whereas the EEU contribution to PPM(2.5) is much higher (43% of total PPM(2.5)) than to SIA (29% of total SIA). The population weighted average concentration (PWC) of PPM(2.5) is a factor of 2.3 higher than average (non-weighted) concentrations, whereas for SIA the PWC is only a factor 1.6 higher. This is due to PPM(2.5) concentrations having larger gradients and being relatively high over densely populated areas, whereas SIA is formed outside populated areas. WEU emissions contribute relatively more than EEU to PWC and mortality due to both PPM(2.5) and SIA in Europe. The number of premature deaths in Europe is estimated to 301000 per year due to PPM(2.5) exposure and 245 000 due to SIA, despite 3.3 times higher average SIA concentrations. This is due to population weighting and assumed (and uncertain) higher relative risk of mortality for PPM(2.5) components (2.8 times higher RR for PPM(2.5)). This study indicates that it might be more efficient, for the health of the European population, to decrease primary PM emissions (especially in WEU) than to decrease precursors of SIA, but more knowledge on the toxicity of different PM constituents is needed before firm conclusions can be drawn. (C) 2009 Elsevier Ltd. All rights reserved.

  • 7. Andersson, Emma
    et al.
    Kahnert, Michael
    SMHI, Forskningsavdelningen, Luftmiljö.
    Coupling aerosol optics to the MATCH (v5.5.0) chemical transport model and the SALSA (v1) aerosol microphysics module2016Inngår i: Geoscientific Model Development, ISSN 1991-959X, E-ISSN 1991-9603, Vol. 9, nr 5, s. 1803-1826Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A new aerosol-optics model is implemented in which realistic morphologies and mixing states are assumed, especially for black carbon particles. The model includes both external and internal mixing of all chemical species, it treats externally mixed black carbon as fractal aggregates, and it accounts for inhomogeneous internal mixing of black carbon by use of a novel "core-grey-shell" model. Simulated results of aerosol optical properties, such as aerosol optical depth, backscattering coefficients and the Angstrom exponent, as well as radiative fluxes are computed with the new optics model and compared with results from an older optics-model version that treats all particles as externally mixed homogeneous spheres. The results show that using a more detailed description of particle morphology and mixing state impacts the aerosol optical properties to a degree of the same order of magnitude as the effects of aerosol-microphysical processes. For instance, the aerosol optical depth computed for two cases in 2007 shows a relative difference between the two optics models that varies over the European region between 28 and 18 %, while the differences caused by the inclusion or omission of the aerosol-microphysical processes range from 50 to 37 %. This is an important finding, suggesting that a simple optics model coupled to a chemical transport model can introduce considerable errors affecting radiative fluxes in chemistry-climate models, compromising comparisons of model results with remote sensing observations of aerosols, and impeding the assimilation of satellite products for aerosols into chemical-transport models.

    Fulltekst (pdf)
    fulltext
  • 8. Arnold, S. R.
    et al.
    Emmons, L. K.
    Monks, S. A.
    Law, K. S.
    Ridley, D. A.
    Turquety, S.
    Tilmes, S.
    Thomas, J. L.
    Bouarar, I.
    Flemming, J.
    Huijnen, V.
    Mao, J.
    Duncan, B. N.
    Steenrod, S.
    Yoshida, Y.
    Langner, Joakim
    SMHI, Forskningsavdelningen, Luftmiljö.
    Long, Y.
    Biomass burning influence on high-latitude tropospheric ozone and reactive nitrogen in summer 2008: a multi-model analysis based on POLMIP simulations2015Inngår i: Atmospheric Chemistry And Physics, ISSN 1680-7316, E-ISSN 1680-7324, Vol. 15, nr 11, s. 6047-6068Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We have evaluated tropospheric ozone enhancement in air dominated by biomass burning emissions at high latitudes (>50 degrees N) in July 2008, using 10 global chemical transport model simulations from the POLMIP multimodel comparison exercise. In model air masses dominated by fire emissions, Delta O-3/Delta CO values ranged between 0.039 and 0.196 ppbv ppbv(-1) (mean: 0.113 ppbv ppbv(-1)) in freshly fire-influenced air, and between 0.140 and 0.261 ppbv ppb(-1) (mean: 0.193 ppbv) in more aged fire-influenced air. These values are in broad agreement with the range of observational estimates from the literature. Model Delta PAN/Delta CO enhancement ratios show distinct groupings according to the meteorological data used to drive the models. ECMWF-forced models produce larger Delta PAN/Delta CO values (4.47 to 7.00 pptv ppbv(-1)) than GEOS5-forced models (1.87 to 3.28 pptv ppbv(-1)), which we show is likely linked to differences in efficiency of vertical transport during poleward export from mid-latitude source regions. Simulations of a large plume of biomass burning and anthropogenic emissions exported from towards the Arctic using a Lagrangian chemical transport model show that 4-day net ozone change in the plume is sensitive to differences in plume chemical composition and plume vertical position among the POLMIP models. In particular, Arctic ozone evolution in the plume is highly sensitive to initial concentrations of PAN, as well as oxygenated VOCs (acetone, acetaldehyde), due to their role in producing the peroxyacetyl radical PAN precursor. Vertical displacement is also important due to its effects on the stability of PAN, and subsequent effect on NOx abundance. In plumes where net ozone production is limited, we find that the lifetime of ozone in the plume is sensitive to hydrogen peroxide loading, due to the production of HOx from peroxide photolysis, and the key role of HO2 + O-3 in controlling ozone loss. Overall, our results suggest that emissions from biomass burning lead to large-scale photochemical enhancement in high-latitude tropospheric ozone during summer.

    Fulltekst (pdf)
    fulltext
  • 9.
    Asker, Christian
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Andersson, Camilla
    SMHI, Forskningsavdelningen, Luftmiljö.
    Segersson, David
    SMHI, Forskningsavdelningen, Luftmiljö.
    CLAIR-O3 - befolkningsexponering marknära ozon i Göteborg och Stockholm2021Rapport (Annet vitenskapelig)
    Abstract [sv]

    Vi har tagit fram en flexibel nedskalningsmetodik för marknära ozon, CLAIR-O3-metoden.Denna metodik nyttjar högupplösta utsläpp av kväveoxider för att skala ner modellberäknatozon på grövre upplösning. Detta har en vinst i form av ökad upplösning i närhet till utsläppav kväveoxider, t.ex. i urban miljö och närhet till stora vägar/industrier/bostadsområden.Metoden tillåter, utöver den ökade upplösningen, även en förbättring (korrigering) avregionalskaliga halter med regionalskaliga mätningar, såsom i MATCH sverigesystemet, mendet är inte nödvändigt utan nedskalningen av marknära ozon kan appliceras direkt påmodellerad bakgrundshalt. I denna studie har vi utgått från nationella bakgrundshalterframtaget med MATCH (5x5km2 upplösning), och korrigerat mot regionalabakgrundsmätningar på timskala.Vi har beräknat timhalter av marknära ozon för två svenska städer, Stockholm och Göteborg,för 2015 på 100x100m2 upplösning och använt dessa för att skatta befolkningsexponering istädernas kommuner. Högst exponering är generellt i Göteborg under 2015, med allra högstexponering i Kungälvs kommun. Högst exponering i Stockholm är i de ostliga kommunernaÖsteråker, Värmdö och Vaxholm medan den lägsta exponeringen är i Sundbyberg, Solna ochStockholms kommun.Våra modellresultat jämför sig väl mot i metoden oberoende mätdata, och mot enregressionsmetod som baseras på regression av mätningar. Denna metodik är tillämpbar överett större område, som hela Sverige, och längre tidsperioder, då den inte är beroende avtillgång till mätdata.Det finns fortsatta möjliga ytterligare metod och modellförbättringar. En förbättringsmöjlighetär förfinad hantering av hur regionalskalig halt först in i nedskalningsmodellen, vilket skullejämna ut det grövre rutmönstret i kartorna. En annan är att införa nedskalning medatmosfärisk stabilitet och höjd i landskapet vilket skulle möjliggöra beskrivning av högupplöstväxtexponering, vilket enbart hanteras i närhet till direkta utsläpp i denna metod.Metoden skulle kunna införas i miljöövervakningen med MATCH Sverigesystemet.

    Fulltekst (pdf)
    CLAIR-O3 - befolkningsexponering marknära ozon i Göteborg och Stockholm
  • 10. Astrom, Christofer
    et al.
    Astrom, Daniel Oudin
    Andersson, Camilla
    SMHI, Forskningsavdelningen, Luftmiljö.
    Ebi, Kristie L.
    Forsberg, Bertil
    Vulnerability Reduction Needed to Maintain Current Burdens of Heat-Related Mortality in a Changing Climate-Magnitude and Determinants2017Inngår i: International Journal of Environmental Research and Public Health, ISSN 1661-7827, E-ISSN 1660-4601, Vol. 14, nr 7, artikkel-id 741Artikkel i tidsskrift (Fagfellevurdert)
    Fulltekst (pdf)
    fulltext
  • 11. Astrom, Christofer
    et al.
    Ebi, Kristie L.
    Langner, Joakim
    SMHI, Forskningsavdelningen, Luftmiljö.
    Forsberg, Bertil
    Developing a Heatwave Early Warning System for Sweden: Evaluating Sensitivity of Different Epidemiological Modelling Approaches to Forecast Temperatures2015Inngår i: International Journal of Environmental Research and Public Health, ISSN 1661-7827, E-ISSN 1660-4601, Vol. 12, nr 1, s. 254-267Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Over the last two decades a number of heatwaves have brought the need for heatwave early warning systems (HEWS) to the attention of many European governments. The HEWS in Europe are operating under the assumption that there is a high correlation between observed and forecasted temperatures. We investigated the sensitivity of different temperature mortality relationships when using forecast temperatures. We modelled mortality in Stockholm using observed temperatures and made predictions using forecast temperatures from the European Centre for Medium-range Weather Forecasts to assess the sensitivity. We found that the forecast will alter the expected future risk differently for different temperature mortality relationships. The more complex models seemed more sensitive to inaccurate forecasts. Despite the difference between models, there was a high agreement between models when identifying risk-days. We find that considerations of the accuracy in temperature forecasts should be part of the design of a HEWS. Currently operating HEWS do evaluate their predictive performance; this information should also be part of the evaluation of the epidemiological models that are the foundation in the HEWS. The most accurate description of the relationship between high temperature and mortality might not be the most suitable or practical when incorporated into a HEWS.

    Fulltekst (pdf)
    fulltext
  • 12. Baldacchini, Chiara
    et al.
    Castanheiro, Ana
    Maghakyan, Nairuhi
    Sgrigna, Gregorio
    Verhelst, Jolien
    Alonso, Rocio
    Amorim, Jorge Humberto
    SMHI, Forskningsavdelningen, Luftmiljö.
    Bellan, Patrick
    Bojovic, Danijela Dunisijevic
    Breuste, Juergen
    Buhler, Oliver
    Cantar, Ilie C.
    Carinanos, Paloma
    Carriero, Giulia
    Churkina, Galina
    Dinca, Lucian
    Esposito, Raffaela
    Gawronski, Stanislaw W.
    Kern, Maren
    Le Thiec, Didier
    Moretti, Marco
    Ningal, Tine
    Rantzoudi, Eleni C.
    Sinjur, Iztok
    Stojanova, Biljana
    Urosevic, Mira Anicic
    Velikova, Violeta
    Zivojinovic, Ivana
    Sahakyan, Lilit
    Calfapietra, Carlo
    Samson, Roeland
    How Does the Amount and Composition of PM Deposited on Platanus acerifolia Leaves Change Across Different Cities in Europe?2017Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 51, nr 3, s. 1147-1156Artikkel i tidsskrift (Fagfellevurdert)
  • 13.
    Bennet, Cecilia
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    A regional model for surface ozone in Southeast Asia2008Inngår i: Tellus. Series B, Chemical and physical meteorology, ISSN 0280-6509, E-ISSN 1600-0889, Vol. 60, nr 5, s. 718-728Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    As part of the model intercomparison study MICS Asia II, the Swedish MATCH model was set up for Southeast and East Asia. In that study, the comprehensive photochemistry scheme of MATCH was used for the first time in Asia. The current work focuses on results of surface ozone from the MATCH model simulations falling outside the model intercomparison study. Model results of surface ozone concentrations for the entire year of 2001 were investigated and compared with measurements in Southeast Asia. The model produced higher surface ozone concentrations than the observations at all of the non-remote stations investigated but underestimated during the dry season at remote locations. Modelled seasonal variation was similar to, but less pronounced than, the variation in the measurements. This study indicates that NO(x) is the limiting precursor for ozone production in the model, while the fractionation in different species and total amount of non-methane volatile organic compounds (NMVOC) emissions are less important. Naturally emitted NMVOC, isoprene, is an important precursor of surface ozone at certain conditions, and a better inventory of these emissions is needed. Deposition velocities of ozone also have impact on surface concentrations. To improve the model performance, it is important to add a land use inventory with corresponding deposition velocities.

    Fulltekst (pdf)
    fulltext
  • 14.
    Bennet, Cecilia
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Jonsson, P
    Lindgren, E S
    Concentrations and sources of trace elements in particulate air pollution, Dar es Salaam, Tanzania, studied by EDXRF2005Inngår i: X-Ray Spectrometry, ISSN 0049-8246, E-ISSN 1097-4539, Vol. 34, nr 1, s. 1-6Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Trace elements in near-ground atmospheric aerosols were investigated in Dar es Salaam, Tanzania. Particles were collected at two sites, one urban and one rural, during, two months with different meteorological conditions. The samplers, dichotomous impactors, segregate the particles into two size fractions, fine (PM2.5, d(a) < 2.5 mum) and coarse (2.5 < d(a) < 10 mum). A sharp cyclone was used to sample finer particles (PM1, d(a) < 1 mum). Meteorological parameters were also examined at both sites. An EDXRF spectrometer, based on three-axial geometry, was used for quantitative elemental analysis. Concentrations of elements heavier than phosphorus were determined. Also, the content of black carbon on the filters was measured with a reflectometer. The elemental concentrations were compared with respect to season and geographical location in the city. The levels of different species in Dar es Salaam were also compared with similar data from other African and European countries. This showed low values of Pb with respect to the size of the city and no legislation on the use of leaded petrol, that often is the main source of lead. High values of Cl were also found, as would be expected in a coastal city. The coarse particles in the air, originating from soil, had a different composition in Dar es Salaam than in Gaborone, Botswana, and the concentration of black carbon was higher than in other cities. On the basis of the data collected, source assignments were made and the following sources found; sea-spray, soil, city road dust, biomass burning industries and traffic. Comparing the concentrations of different elements in PM2.5 and PM1 revealed that black carbon, Zn, Pb, K and Br are present only in the smallest particles. Copyright (C) 2005 John Wiley Sons, Ltd.

  • 15.
    Bergström, Robert
    SMHI, Forskningsavdelningen, Luftmiljö.
    How should condensables be included in PM emission inventories reported to EMEP/CLRTAP?2020Inngår i: EMEP, ISSN 1504-6206, nr 4, s. 1-72Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    Condensable primary organic aerosol emissions are a class of organic compounds that arevapour phase at stack conditions, but which undergo both condensation and evaporation processes as the stack air is cooled and diluted upon discharge into ambient air. Emission factorsmeasured in or close to the high-temperature high-concentration exhaust stack or pipe maymisrepresent, and even miss, the amount of PM or gas that actually enters the atmosphere,depending on the filters, dilution and sampling conditions of the emission measurement. Inthe current emission reporting to EMEP/CLRTAP there is no clear definition of whether condensable organics are included or not, and, if included, to what extent.

    In March 2020 MSC-W hosted an expert workshop on condensable organic aerosol emissions (funded by the Nordic Council of Ministers), which brought together experts in emissions, measurements, emission inventories, atmospheric chemistry, air quality models andpolicy from Europe and North America, and to create a much better understanding of theissues and possible approaches for dealing with this important class of compounds.

    More than 30 experts took part in the (zoom) meeting, including EMEP Chairs (EMEPSteering Body, TFIAM, TFMM, TFEIP, TFTEI), EMEP Centres (MSC-W, CEIP, CIAM),inventory developers (TNO, CIAM, COPERT, and national experts from UBA - Germany,SINTEF - Norway, IVL, ACES, Swedish EPA - Sweden, CITEPA, INERIS - France, ECCC- Canada, Univ. Patras - Greece), measurement experts (PSI - Switzerland, INERIS - France,Univ. York - England, NC State University - USA), industry (Concawe), the US EPA and theEuropean Commission. The workshop discussed a number of approaches for dealing with thisimportant class of compounds. This executive summary presents some of the key messagesfrom the workshop. Further background, addressing the technical matters in more detail canbe found in the main body of the report.

    The main idea of the workshop was to promote discussion among different communitiesand Task Forces that have different expertise and needs with regard to condensable organics and PM emission inventories. In order to aid these discussions, a number of importantquestions were identified:

    1. For which source categories are condensable organics important?

    2. What is included in official national and other emission inventories?

    3. Do we expect emissions of condensable organics to be missing in these inventories?

    4. Can we reliably predict the contribution of condensable vapours from major sources toambient PM using data from a smaller number of representative cases?

    5. Can we recommend a practical approach for inclusion (or exclusion) of condensables in (a) emission inventories, and (b) chemical transport models?

    One of the ongoing major tasks for the Air Convention (CLRTAP) is the revision of the socalled ‘Gothenburg’ Protocol 1, with a final report of the review to be completed during 2022.It is important to note that for this review process, the consideration of condensables facesseveral (competing) challenges:

    (a) The need for emission data as soon as possible that are consistent across countries inorder to get a fair ‘optimised’ distribution of emission abatement efforts aimed at improving health and ecosystems protection targets;

    (b) The difficulties to change existing practices of some countries;

    (c) The wish of scientists to start multi-year work programs for the best possible way todefine and quantify condensable emissions and/or secondary PM formation in the atmosphere.

    (d) The need to assess the available options for short and longer term actions in terms ofe.g. time frame (feas

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    How should condensables be included in PM emission inventories reported to EMEP/CLRTAP?
  • 16.
    Bergström, Robert
    SMHI, Forskningsavdelningen, Luftmiljö.
    Transboundary particulate matter, photo-oxidants, acidifying and eutrophying components2020Inngår i: EMEP, ISSN 1504-6192, nr 1, s. 1-270Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    This report presents the EMEP activities in 2019 and 2020 in relation to transboundary fluxesof particulate matter, photo-oxidants, acidifying and eutrophying components, with focus onresults for 2018. It presents major results of the activities related to emission inventories,observations and modelling. The report also introduces specific relevant research activitiesaddressing EMEP key challenges, as well as technical developments of the observation andmodelling capacities.

    Fulltekst (pdf)
    Transboundary particulate matter, photo-oxidants, acidifying and eutrophying components
  • 17.
    Bergström, Robert
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Hallquist, M.
    Simpson, D.
    Wildt, J.
    Mentel, T. F.
    Biotic stress: a significant contributor to organic aerosol in Europe?2014Inngår i: Atmospheric Chemistry And Physics, ISSN 1680-7316, E-ISSN 1680-7324, Vol. 14, nr 24, s. 13643-13660Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We have investigated the potential impact on organic aerosol formation from biotic stress-induced emissions (SIE) of organic molecules from forests in Europe (north of lat. 45 degrees N). Emission estimates for sesquiterpenes (SQT), methyl salicylate (MeSA) and unsaturated C-17 compounds, due to different stressors, are based on experiments in the Julich Plant Atmosphere Chamber (JPAC), combined with estimates of the fraction of stressed trees in Europe based on reported observed tree damage. SIE were introduced in the EMEP MSC-W chemical transport model and secondary organic aerosol (SOA) yields from the SIE were taken from the JPAC experiments. Based on estimates of current levels of infestation and the JPAC aerosol yields, the model results suggest that the contribution to SOA in large parts of Europe may be substantial. It is possible that SIE contributes as much, or more, to organic aerosol than the constitutive biogenic VOC emissions, at least during some periods. Based on the assumptions in this study, SIE-SOA are estimated to constitute between 50 and 70% of the total biogenic SOA (BSOA) in a current-situation scenario where the biotic stress in northern and central European forests causes large SIE of MeSA and SQT. An alternative current-situation scenario with lower SIE, consisting solely of SQT, leads to lower SIE-SOA, between 20 and 40% of the total BSOA. Hypothetical future scenarios with increased SIE, due to higher degrees of biotic stress, show that SOA formation due to SIE can become even larger. Unsaturated C17 BVOC (biogenic volatile organic compounds) emitted by spruce infested by the forest-honey generating bark louse, Cinara pilicornis, have a high SOA-forming potential. A model scenario investigating the effect of a regional, episodic infestation of Cinara pilicornis in Baden-Wurttemberg, corresponding to a year with high production of forest honey, shows that these types of events could lead to very large organic aerosol formation in the infested region. We have used the best available laboratory data on biotic SIE applicable to northern and central European forests. Using these data and associated assumptions, we have shown that SIE are potentially important for SOA formation but the magnitude of the impact is uncertain and needs to be constrained by further laboratory, field and modelling studies. As an example, the MeSA, which is released as a consequence of various types of biotic stress, is found to have a potentially large impact on SIE-SOA in Europe, but different assumptions regarding the nighttime chemistry of MeSA can change its SOA potential substantially. Thus, further investigations of the atmospheric chemistry of MeSA and observational field studies are needed to clarify the role of this compound in the atmosphere.

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  • 18.
    Bergström, Robert
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    van der Gon, H. A. C. Denier
    Prevot, A. S. H.
    Yttri, K. E.
    Simpson, D.
    Modelling of organic aerosols over Europe (2002-2007) using a volatility basis set (VBS) framework: application of different assumptions regarding the formation of secondary organic aerosol2012Inngår i: Atmospheric Chemistry And Physics, ISSN 1680-7316, E-ISSN 1680-7324, Vol. 12, nr 18, s. 8499-8527Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A new organic aerosol module has been implemented into the EMEP chemical transport model. Four different volatility basis set (VBS) schemes have been tested in long-term simulations for Europe, covering the six years 2002-2007. Different assumptions regarding partitioning of primary organic aerosol and aging of primary semi-volatile and intermediate volatility organic carbon (S/IVOC) species and secondary organic aerosol (SOA) have been explored. Model results are compared to filter measurements, aerosol mass spectrometry (AMS) data and source apportionment studies, as well as to other model studies. The present study indicates that many different sources contribute significantly to organic aerosol in Europe. Biogenic and anthropogenic SOA, residential wood combustion and vegetation fire emissions may all contribute more than 10% each over substantial parts of Europe. This study shows smaller contributions from biogenic SOA to organic aerosol in Europe than earlier work, but relatively greater anthropogenic SOA. Simple VBS based organic aerosol models can give reasonably good results for summer conditions but more observational studies are needed to constrain the VBS parameterisations and to help improve emission inventories. The volatility distribution of primary emissions is one important issue for further work. Emissions of volatile organic compounds from biogenic sources are also highly uncertain and need further validation. We can not reproduce winter levels of organic aerosol in Europe, and there are many indications that the present emission inventories substantially underestimate emissions from residential wood combustion in large parts of Europe.

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    fulltext
  • 19. Borrego, C.
    et al.
    Amorim, Jorge Humberto
    SMHI, Forskningsavdelningen, Luftmiljö.
    Tchepel, O.
    Dias, D.
    Rafael, S.
    Sa, E.
    Pimentel, C.
    Fontes, T.
    Fernandes, P.
    Pereira, S. R.
    Bandeira, J. M.
    Coelho, M. C.
    Urban scale air quality modelling using detailed traffic emissions estimates2016Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 131, s. 341-351Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The atmospheric dispersion of NOx and PM10 was simulated with a second generation Gaussian model over a medium-size south-European city. Microscopic traffic models calibrated with GPS data were used to derive typical driving cycles for each road link, while instantaneous emissions were estimated applying a combined Vehicle Specific Power/Co-operative Programme for Monitoring and Evaluation of the Long-range Transmission of Air Pollutants in Europe (VSP/EMEP) methodology. Site-specific background concentrations were estimated using time series analysis and a low-pass filter applied to local observations. Air quality modelling results are compared against measurements at two locations for a 1 week period. 78% of the results are within a factor of two of the observations for 1-h average concentrations, increasing to 94% for daily averages. Correlation significantly improves when background is added, with an average of 0.89 for the 24 h record. The results highlight the potential of detailed traffic and instantaneous exhaust emissions estimates, together with filtered urban background, to provide accurate input data to Gaussian models applied at the urban scale. (C) 2016 Elsevier Ltd. All rights reserved.

  • 20. Burton, S. P.
    et al.
    Hair, J. W.
    Kahnert, Michael
    SMHI, Forskningsavdelningen, Luftmiljö.
    Ferrare, R. A.
    Hostetler, C. A.
    Cook, A. L.
    Harper, D. B.
    Berkoff, T. A.
    Seaman, S. T.
    Collins, J. E.
    Fenn, M. A.
    Rogers, R. R.
    Observations of the spectral dependence of linear particle depolarization ratio of aerosols using NASA Langley airborne High Spectral Resolution Lidar2015Inngår i: Atmospheric Chemistry And Physics, ISSN 1680-7316, E-ISSN 1680-7324, Vol. 15, nr 23, s. 13453-13473Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Linear particle depolarization ratio is presented for three case studies from the NASA Langley airborne High Spectral Resolution Lidar-2 (HSRL-2). Particle depolarization ratio from lidar is an indicator of non-spherical particles and is sensitive to the fraction of non-spherical particles and their size. The HSRL-2 instrument measures depolarization at three wavelengths: 355, 532, and 1064 nm. The three measurement cases presented here include two cases of dust-dominated aerosol and one case of smoke aerosol. These cases have partial analogs in earlier HSRL-1 depolarization measurements at 532 and 1064 nm and in literature, but the availability of three wavelengths gives additional insight into different scenarios for non-spherical particles in the atmosphere. A case of transported Saharan dust has a spectral dependence with a peak of 0.30 at 532 nm with smaller particle depolarization ratios of 0.27 and 0.25 at 1064 and 355 nm, respectively. A case of aerosol containing locally generated wind-blown North American dust has a maximum of 0.38 at 1064 nm, decreasing to 0.37 and 0.24 at 532 and 355 nm, respectively. The cause of the maximum at 1064 nm is inferred to be very large particles that have not settled out of the dust layer. The smoke layer has the opposite spectral dependence, with the peak of 0.24 at 355 nm, decreasing to 0.09 and 0.02 at 532 and 1064 nm, respectively. The depolarization in the smoke case may be explained by the presence of coated soot aggregates. We note that in these specific case studies, the linear particle depolarization ratio for smoke and dust-dominated aerosol are more similar at 355 nm than at 532 nm, having possible implications for using the particle depolarization ratio at a single wavelength for aerosol typing.

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  • 21. Carlsen, Hanne Krage
    et al.
    Nyberg, Fredrik
    Toren, Kjell
    Segersson, David
    SMHI, Forskningsavdelningen, Luftmiljö.
    Olin, Anna-Carin
    Exposure to traffic-related particle matter and effects on lung function and potential interactions in a cross-sectional analysis of a cohort study in west Sweden2020Inngår i: BMJ Open, E-ISSN 2044-6055, Vol. 10, nr 10, artikkel-id e034136Artikkel i tidsskrift (Fagfellevurdert)
    Fulltekst (pdf)
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  • 22. Carmichael, G R
    et al.
    Calori, G
    Hayami, H
    Uno, I
    Cho, S Y
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    Kim, S B
    Ichikawa, Y
    Ikeda, Y
    Woo, J H
    Ueda, H
    Amann, M
    The MICS-Asia study: model intercomparison of long-range transport and sulfur deposition in East Asia2002Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 36, nr 2, s. 175-199Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An intercomparison study involving eight long-range transport models for sulfur deposition in East Asia has been initiated, The participating models included Eulerian and Lagrangian frameworks, with a wide variety of vertical resolutions and numerical approaches. Results from this study, in which models used common data sets for emissions, meteorology, and dry, wet and chemical conversion rates, are reported and discussed. Model results for sulfur dioxide and sulfate concentrations, wet deposition amounts, for the period January and May 1993, are compared with observed quantities at 18 surface sites in East Asia. At many sites the ensemble of models is found to have high skill in predicting observed quantities. At other sites all models show poor predictive capabilities. Source-receptor relationships estimated by the models are also compared. The models show a high degree of consistency in identifying the main source-receptor relationships, as well as in the relative contributions of wet/dry pathways for removal. But at some locations estimated deposition amounts can vary by a factor or 5. The influence of model structure and parameters on model performance is discussed. The main factors determining the deposition fields are the emissions and underlying meteorological fields. Model structure in terms of vertical resolution is found to be more important than the parameterizations used for chemical conversion and removal, as these processes are highly coupled and often work in compensating directions. (C) 2002 Elsevier Science Ltd. All rights reserved.

  • 23. Carmichael, G R
    et al.
    Hayami, H
    Calori, G
    Uno, I
    Cho, S Y
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    Kim, S B
    Ichikawa, Y
    Ikeda, Y
    Ueda, H
    Amann, M
    Model intercomparison study of long range transport and sulfur deposition in East Asia (MICS-ASIA)2001Inngår i: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 130, nr 1-4, s. 51-62Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To help improve the use of models in science & policy analysis in Asia it is necessary to have a better understanding of model performance and uncertainties. Towards this goal an intercomparison exercise has been initiated as a collaborative study of scientists interested in long-range transport in East Asia. An overview of this study is presented in this paper. The study consists of a set of prescribed test calculations with carefully controlled experiments. Models used the same domain, emission inventory, model parameters, meteorological conditions, etc. Two periods (January and May 1993) were selected to reflect long-range transport conditions under two distinct seasons. During these periods measurements of sulfur concentrations and deposition were made throughout the study region using identical sampling and analysis protocols. The intercomparison activity consists of four tasks (Blind Test, Fixed Parameter Test, Source Receptor test, and Tuning Test). All participants were asked to do Task A, and as many of the other tasks as possible. To date seven different models have participated in this study. Results and key findings are presented.

  • 24. Carmichael, G. R.
    et al.
    Sakurai, T.
    Streets, D.
    Hozumi, Y.
    Ueda, H.
    Park, S. U.
    Fung, C.
    Han, Z.
    Kajino, M.
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    Bennet, Cecilia
    SMHI, Forskningsavdelningen, Luftmiljö.
    Hayami, H.
    Sartelet, K.
    Holloway, T.
    Wang, Z.
    Kannari, A.
    Fu, J.
    Matsuda, K.
    Thongbooncho, N.
    Amann, M.
    MICS-Asia II: The model intercomparison study for Asia Phase II methodology and overview of findings2008Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 42, nr 15, s. 3468-3490Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Results from the Model Intercomparison Study Asia Phase II (MICS-Asia II) are presented. Nine different regional modeling groups simulated chemistry and transport of ozone (O-3), secondary aerosol, acid deposition, and associated precursors, using common emissions and boundary conditions derived from a global model. Four-month-long periods, representing 2 years and three seasons (i.e., March, July, and December in 2001, and March in 2002), are analyzed. New observational data, obtained under the EANET (the Acid Deposition Monitoring Network in East Asia) monitoring program, were made available for this study, and these data provide a regional database to compare with model simulations. The analysis focused around seven subject areas: O-3 and related precursors, aerosols, acid deposition, global inflow of pollutants and precursor to Asia, model sensitivities to aerosol parameterization, analysis of emission fields, and detailed analyses of individual models, each of which is presented in a companion paper in this issue of Atmospheric Environment. This overview discusses the major findings of the study, as well as information on common emissions, meteorological conditions, and observations. (C) 2007 Elsevier Ltd. All rights reserved.

  • 25. Colette, Augustin
    et al.
    Andersson, Camilla
    SMHI, Forskningsavdelningen, Luftmiljö.
    Baklanov, Alexander
    Bessagnet, Bertrand
    Brandt, Jorgen
    Christensen, Jesper H.
    Doherty, Ruth
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    Geels, Camilla
    Giannakopoulos, Christos
    Hedegaard, Gitte B.
    Katragkou, Eleni
    Langner, Joakim
    SMHI, Forskningsavdelningen, Luftmiljö.
    Lei, Hang
    Manders, Astrid
    Melas, Dimitris
    Meleux, Frederik
    Rouil, Laurence
    Sofiev, Mikhail
    Soares, Joana
    Stevenson, David S.
    Tombrou-Tzella, Maria
    Varotsos, Konstantinos V.
    Young, Paul
    Is the ozone climate penalty robust in Europe?2015Inngår i: Environmental Research Letters, E-ISSN 1748-9326, Vol. 10, nr 8, artikkel-id 084015Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ozone air pollution is identified as one of the main threats bearing upon human health and ecosystems, with 25 000 deaths in 2005 attributed to surface ozone in Europe (IIASA 2013 TSAP Report #10). In addition, there is a concern that climate change could negate ozone pollution mitigation strategies, making them insufficient over the long run and jeopardising chances to meet the long term objective set by the European Union Directive of 2008 (Directive 2008/50/EC of the European Parliament and of the Council of 21 May 2008) (60 ppbv, daily maximum). This effect has been termed the ozone climate penalty. One way of assessing this climate penalty is by driving chemistry-transport models with future climate projections while holding the ozone precursor emissions constant (although the climate penalty may also be influenced by changes in emission of precursors). Here we present an analysis of the robustness of the climate penalty in Europe across time periods and scenarios by analysing the databases underlying 11 articles published on the topic since 2007, i.e. a total of 25 model projections. This substantial body of literature has never been explored to assess the uncertainty and robustness of the climate ozone penalty because of the use of different scenarios, time periods and ozone metrics. Despite the variability of model design and setup in this database of 25 model projection, the present meta-analysis demonstrates the significance and robustness of the impact of climate change on European surface ozone with a latitudinal gradient from a penalty bearing upon large parts of continental Europe and a benefit over the North Atlantic region of the domain. Future climate scenarios present a penalty for summertime (JJA) surface ozone by the end of the century (2071-2100) of at most 5 ppbv. Over European land surfaces, the 95% confidence interval of JJA ozone change is [0.44; 0.64] and [0.99; 1.50] ppbv for the 2041-2070 and 2071-2100 time windows, respectively.

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  • 26. Colette, Augustin
    et al.
    Schucht, Simone
    Ciarelli, Giancarlo
    Létinois, Laurent
    Meleux, Frédérik
    Andersson, Camilla
    SMHI, Forskningsavdelningen, Luftmiljö.
    Cuvelier, C.
    Manders, A.
    Mar, K.A.
    Mircea, M.
    Pay, T.
    Raffort, V.
    Tsyro, S.
    Adani, M.
    Bergström, Robert
    SMHI, Forskningsavdelningen, Luftmiljö.
    Bessagnet, G
    Briganti, A.
    Cappelletti, A.
    Couvidat, F.
    D'Isidoro, M.
    Fagerli, H.
    Ojha, N.
    Otero, N.
    Wind, P.
    Long-term air quality trends in Europe Fine Particulate Matter (PM2.5) Health Impacts.2018Rapport (Annet vitenskapelig)
  • 27. De Geer, Lars-Erik
    et al.
    Persson, Christer
    SMHI, Forskningsavdelningen, Luftmiljö.
    Rodhe, Henning
    A Nuclear Jet at Chernobyl Around 21:23:45 UTC on April 25, 19862018Inngår i: Nuclear Technology, ISSN 0029-5450, E-ISSN 1943-7471, Vol. 201, nr 1, s. 11-22Artikkel i tidsskrift (Fagfellevurdert)
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  • 28. Dias, Daniela
    et al.
    Amorim, Jorge Humberto
    SMHI, Forskningsavdelningen, Luftmiljö.
    Sa, Elisa
    Borrego, Carlos
    Fontes, Tania
    Fernandes, Paulo
    Pereira, Sergio Ramos
    Bandeira, Jorge
    Coelho, Margarida C.
    Tchepel, Oxana
    Assessing the importance of transportation activity data for urban emission inventories2018Inngår i: Transportation Research Part D: Transport and Environment, ISSN 1361-9209, E-ISSN 1879-2340, Vol. 62, s. 27-35Artikkel i tidsskrift (Fagfellevurdert)
  • 29. Eckhardt, S.
    et al.
    Quennehen, B.
    Olivie, D. J. L.
    Berntsen, T. K.
    Cherian, R.
    Christensen, J. H.
    Collins, W.
    Crepinsek, S.
    Daskalakis, N.
    Flanner, M.
    Herber, A.
    Heyes, C.
    Hodnebrog, O.
    Huang, L.
    Kanakidou, M.
    Klimont, Z.
    Langner, Joakim
    SMHI, Forskningsavdelningen, Luftmiljö.
    Law, K. S.
    Lund, M. T.
    Mahmood, R.
    Massling, A.
    Myriokefalitakis, S.
    Nielsen, I. E.
    Nojgaard, J. K.
    Quaas, J.
    Quinn, P. K.
    Raut, J. -C
    Rumbold, S. T.
    Schulz, M.
    Sharma, S.
    Skeie, R. B.
    Skov, H.
    Uttal, T.
    von Salzen, K.
    Stohl, A.
    Current model capabilities for simulating black carbon and sulfate concentrations in the Arctic atmosphere: a multi-model evaluation using a comprehensive measurement data set2015Inngår i: Atmospheric Chemistry And Physics, ISSN 1680-7316, E-ISSN 1680-7324, Vol. 15, nr 16, s. 9413-9433Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The concentrations of sulfate, black carbon (BC) 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 and especially the high concentrations associated with Arctic Haze. In this study, we evaluate sulfate and BC concentrations from eleven different models driven with the same emission inventory against a comprehensive pan-Arctic measurement data set over a time period of 2 years (2008-2009). The set of models consisted of one Lagrangian particle dispersion model, four chemistry transport models (CTMs), one atmospheric chemistry-weather forecast model and five chemistry climate models (CCMs), of which two were nudged to meteorological analyses and three were running freely. The measurement data set consisted of surface measurements of equivalent BC (eBC) from five stations (Alert, Barrow, Pallas, Tiksi and Zeppelin), elemental carbon (EC) from Station Nord and Alert and aircraft measurements of refractory BC (rBC) from six different campaigns. We find that the models generally captured the measured eBC or rBC and sulfate concentrations quite well, compared to previous comparisons. However, the aerosol seasonality at the surface is still too weak in most models. Concentrations of eBC and sulfate averaged over three surface sites are underestimated in winter/spring in all but one model (model means for January-March underestimated by 59 and 37% for BC and sulfate, respectively), whereas concentrations in summer are overestimated in the model mean (by 88 and 44% for July-September), but with overestimates as well as underestimates present in individual models. The most pronounced eBC underestimates, not included in the above multi-site average, are found for the station Tiksi in Siberia where the measured annual mean eBC concentration is 3 times higher than the average annual mean for all other stations. This suggests an underestimate of BC sources in Russia in the emission inventory used. Based on the campaign data, biomass burning was identified as another cause of the modeling problems. For sulfate, very large differences were found in the model ensemble, with an apparent anti-correlation between modeled surface concentrations and total atmospheric columns. There is a strong correlation between observed sulfate and eBC concentrations with consistent sulfate/eBC slopes found for all Arctic stations, indicating that the sources contributing to sulfate and BC are similar throughout the Arctic and that the aerosols are internally mixed and undergo similar removal. However, only three models reproduced this finding, whereas sulfate and BC are weakly correlated in the other models. Overall, no class of models (e.g., CTMs, CCMs) performed better than the others and differences are independent of model resolution.

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  • 30. Emberson, L. D.
    et al.
    Bueker, P.
    Ashmore, M. R.
    Mills, G.
    Jackson, L. S.
    Agrawal, M.
    Atikuzzaman, M. D.
    Cinderby, S.
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    Jamir, C.
    Kobayashi, K.
    Oanh, N. T. K.
    Quadir, Q. F.
    Wahid, A.
    A comparison of North American and Asian exposure-response data for ozone effects on crop yields2009Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 43, nr 12, s. 1945-1953Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Modelling-based studies to assess the extent and magnitude of ozone (O-3) risk to agriculture in Asia suggest that yield losses of 5-20% for important crops may be common in areas experiencing elevated O-3 concentrations. These assessments have relied on European and North American dose-response relationships and hence assumed an equivalent Asian crop response to O-3 for local cultivars, pollutant conditions and climate. To test this assumption we collated comparable dose-response data derived from fumigation, filtration and EDU experiments conducted in Asia on wheat. rice and leguminous crop species. These data are pooled and compared with equivalent North American dose-response relationships. The Asian data show that at ambient O-3 concentrations found at the study sites (which vary between similar to 35-75 ppb 4-8 h growing season mean), yield losses for wheat, rice and legumes range between 5-48, 3-47 and 10-65%, respectively. The results indicate that Asian grown wheat and rice cultivars are more sensitive to O-3 than the North American dose-response relationships would suggest. For legumes the scatter in the data makes it difficult to reach any equivalent conclusion in relative sensitivities. As such, existing modelling-based risk assessments may have substantially underestimated the scale of the problem in Asia through use of North American derived dose-response relationships. (c) 2009 Elsevier Ltd. All rights reserved.

  • 31. Emmons, L. K.
    et al.
    Arnold, S. R.
    Monks, S. A.
    Huijnen, V.
    Tilmes, S.
    Law, K. S.
    Thomas, J. L.
    Raut, J. -C
    Bouarar, I.
    Turquety, S.
    Long, Y.
    Duncan, B.
    Steenrod, S.
    Strode, S.
    Flemming, J.
    Mao, J.
    Langner, Joakim
    SMHI, Forskningsavdelningen, Luftmiljö.
    Thompson, A. M.
    Tarasick, D.
    Apel, E. C.
    Blake, D. R.
    Cohen, R. C.
    Dibb, J.
    Diskin, G. S.
    Fried, A.
    Hall, S. R.
    Huey, L. G.
    Weinheimer, A. J.
    Wisthaler, A.
    Mikoviny, T.
    Nowak, J.
    Peischl, J.
    Roberts, J. M.
    Ryerson, T.
    Warneke, C.
    Helmig, D.
    The POLARCAT Model Intercomparison Project (POLMIP): overview and evaluation with observations2015Inngår i: Atmospheric Chemistry And Physics, ISSN 1680-7316, E-ISSN 1680-7324, Vol. 15, nr 12, s. 6721-6744Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A model intercomparison activity was inspired by the large suite of observations of atmospheric composition made during the International Polar Year (2008) in the Arctic. Nine global and two regional chemical transport models participated in this intercomparison and performed simulations for 2008 using a common emissions inventory to assess the differences in model chemistry and transport schemes. This paper summarizes the models and compares their simulations of ozone and its precursors and presents an evaluation of the simulations using a variety of surface, balloon, aircraft and satellite observations. Each type of measurement has some limitations in spatial or temporal coverage or in composition, but together they assist in quantifying the limitations of the models in the Arctic and surrounding regions. Despite using the same emissions, large differences are seen among the models. The cloud fields and photolysis rates are shown to vary greatly among the models, indicating one source of the differences in the simulated chemical species. The largest differences among models, and between models and observations, are in NOy partitioning (PAN vs. HNO3) and in oxygenated volatile organic compounds (VOCs) such as acetaldehyde and acetone. Comparisons to surface site measurements of ethane and propane indicate that the emissions of these species are significantly underestimated. Satellite observations of NO2 from the OMI (Ozone Monitoring Instrument) have been used to evaluate the models over source regions, indicating anthropogenic emissions are underestimated in East Asia, but fire emissions are generally overestimated. The emission factors for wildfires in Canada are evaluated using the correlations of VOCs to CO in the model output in comparison to enhancement factors derived from aircraft observations, showing reasonable agreement for methanol and acetaldehyde but underestimate ethanol, propane and acetone, while overestimating ethane emission factors.

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  • 32.
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    Assessing ground-level ozone (O3) impacts to crops in parts of Asia and southern Africa: The Regional Air Pollution in Developping Countries (RAPIDC) Crops Project.2010Inngår i: Air Pollution Health and Environmental Impacts, CRC Press , 2010, s. 421-446Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 33.
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    Modelling of near-surface ozone over South Asia2008Inngår i: Journal of Atmospheric Chemistry, ISSN 0167-7764, E-ISSN 1573-0662, Vol. 59, nr 1, s. 61-80Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Hourly, three-dimensional, fields of tropospheric ozone have been produced for 12 consecutive months on a domain covering South Asia, using the regional Eulerian off-line chemistry transport model MATCH. The results were compared with background observations to investigate diurnal and seasonal variations of near-surface ozone in the region. MATCH reproduced the seasonality of near-surface ozone at most locations in the area. However, the current, and previous, studies indicate that the model consequently overestimate night-time concentrations, while it occasionally underestimates the day-time, near-surface, ozone concentrations. The lowest monthly-mean concentrations of near-surface ozone are typically experienced in June-September, coincident with the rainy season in most areas. The seasonality is not identical across the domain; some locations have a completely different trend. Large areas in Northern India and Nepal show a secondary minimum during the cold winter season (December-January). High concentrations of near-surface ozone are found over the oceans, close to the Indian subcontinent, due to the less efficient dry deposition to water surfaces; over parts of Tibet due to influence of free tropospheric air and little deposition to snow covered surfaces; and along the Gangetic valley due to the large emissions of precursors in this region. Monthly-mean ozone concentrations in the densely populated northern India range from 30-45 ppb(v). The model results were also used to produce maps of AOT40. The results point towards similar levels of AOT40 in India as in Europe: large areas of India show 3-month AOT40 values above 3 ppm(v) hours.

  • 34.
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    Sulphur simulations for East Asia using the match model with meteorological data from ECMWF2001Inngår i: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 130, nr 1-4, s. 289-294Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Sulphur transport and conversion calculations have been conducted over an East Asian domain as part of a model intercomparison exercise. We hereby describe the MATCH model, used in the study, and discuss the results achieved with different model configurations. We find that is often more critical to choose a representative gridbox value than selecting a specific parameter value from the suite available. The modelled, near-surface, atmospheric concentration of total-sulphur (SO2+sulphate) in eastern China is typically 5-10 mug S m(-3), with large areas exceeding 20 mug S m(3). In southern Japan the values range from 2-5 mug S m(-3). Atmospheric SO2 dominates over sulphate near the emission regions while sulphate concentrations are higher over e.g. the western Pacific. The sulphur deposition exceeds several g sulphur m(-2) year m(-1) in large areas of China. Southern Japan receives 0.5-1 S m(-2) year(-1).

  • 35.
    Engardt, Magnuz
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Alpfjord, Helene
    SMHI, Affärsverksamhet.
    Andersson, Camilla
    SMHI, Forskningsavdelningen, Luftmiljö.
    PODY-beräkningar med MATCH Sverigesystemet2016Rapport (Annet vitenskapelig)
    Abstract [sv]

    Vi har utvecklat ett programpaket som möjliggör PODY beräkningar i MATCH Sverigesystemet. Rapporten ger en kortfattad introduktion till PODY och går igenom implementeringen i MATCH-systemet.

    Resultat för receptorerna generic crops (POD3gen-CR) och generic deciduous trees (POD1gen-DT) presenteras för åren 2013-2015 och jämförs med motsvarande data från EMEP-modellen. POD3gen-CR uppvisar stor år-till-år variation och MATCH-resultaten är tydligt högre än motsvarande uppskattningar av EMEP-modellen. POD1gen-DT varierar mindre från år till år och resultaten från MATCH och EMEP-modellen överensstämmer bättre.

    PODY presenteras tillsammans med övriga ozonmått på SMHI:s miljöövervakningssida (www.smhi.se/klimatdata/miljo/atmosfarskemi) med start från miljöövervakningsåret 2013.

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  • 36.
    Engardt, Magnuz
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Bergström, Robert
    SMHI, Forskningsavdelningen, Luftmiljö.
    Andersson, Camilla
    SMHI, Forskningsavdelningen, Luftmiljö.
    Climate and Emission Changes Contributing to Changes in Near-surface Ozone in Europe over the Coming Decades: Results from Model Studies2009Inngår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 38, nr 8, s. 452-458Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We used an off-line, regional, model of atmospheric transport and chemistry to investigate current and future levels of near-surface ozone and accumulated ozone exposure over a threshold of 40 ppb(v) (AOT40) in Europe. To describe the current situation and enable an evaluation of the model's performance we simulated a number of years around 2000. To assess changes in ozone concentrations due to possible emission changes in Europe, the model was run with the meteorology of the early 2000s and precursor emissions from a set of Clean Air for Europe (CAFE) emissions scenarios. By extrapolation of the observed increase in near-surface O(3) at coastal locations in northwest Europe we constructed model boundaries that were used to simulate the impact of increasing hemispheric background in 2020. To assess changes in ozone concentrations due to climate change, the model was run with recent (2000) emissions but using meteorology from a regional climate model simulating a control (1961-1990) and a future (2021-2050) climate. The results indicate that climate change will have a small impact on ozone concentrations and AOT40 in the Nordic countries. Changes in hemispheric background concentrations and changes in precursor emissions in Europe will have a larger effect on ozone in Northern Europe. The situation is quite different in southern Europe, where climate change is expected to result in a very large increase in near-surface ozone concentrations.

  • 37.
    Engardt, Magnuz
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Holmen, K
    Model simulations of anthropogenic-CO2 transport to an Arctic monitoring station during winter1999Inngår i: Tellus. Series B, Chemical and physical meteorology, ISSN 0280-6509, E-ISSN 1600-0889, Vol. 51, nr 2, s. 194-209Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We describe, and use, a limited area, 3-dimensional transport model. The model domain is located over the Arctic, but includes the majority of the anthropogenic CO2 emissions in western and eastern Europe, which together make up about 1/3 of the global CO2 emissions. The model is run for several winter periods, using anthropogenic CO2 emissions only, and the results are compared with independent CO2 measurements taken at a monitoring station on Spitsbergen in the high Arctic. We show that the initial concentrations and boundary values of the domain are not crucial for the results, and conclude that most of the measured variability above the winter baseline in CO2 at the Arctic monitoring station emanates from recent CO2 sources within the model domain. From the observed small spatial variability in the monthly mean atmospheric CO2 mixing ratio in the north Atlantic region, we assume that there is only little net exchange between the atmosphere and ocean during the studied periods. Based on the co-variation between CO2 and particulate mass,we hypothesise that most of the measured CO2 variability is due to anthropogenic fossil fuel emissions, although we can not rule out a biogenic CO2 component. Using the transport model, we compare different estimates of fossil-fuel consumption in the mid-latitudes. We find that the industrial centres and the surrounding gas-fields in the lower-Ob region (60 degrees-72 degrees N, 65 degrees-80 degrees E) occasionally have a much larger impact on the CO2 measurements at Spitsbergen than follows from a recent CO2 emission inventory. This implies that there may be an overlooked CO2 source in this region, possibly flaring of gas.

    Fulltekst (pdf)
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  • 38.
    Engardt, Magnuz
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Leong, C P
    Regional modelling of anthropogenic sulphur in Southeast Asia2001Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 35, nr 34, s. 5935-5947Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A co-operative research project between the Malaysian Meteorological Service (MMS) and the Swedish Meteorological and Hydrological Institute (SMHI) focussing on the usage of an atmospheric transport and chemistry model, has just been initiated. Here, we describe the main features of the dispersion model and discuss a first set of calculations in light of available measurements of sulphuric species in Southeast Asia. According to our results, anthropogenic sulphur concentrations and depositions are particularly high near the large cities of the region, around a metal smelter in the southern Philippines, and in a region extending from northern Vietnam into southeastern China. These areas coincide with the high-emissions regions of Southeast Asia and we tentatively conclude that regional transport of acidifying species is not as far-reaching as in the mid-latitudes. From our calculations, and from supporting measurements we conclude that most of rural Southeast Asia is not yet severely affected by anthropogenic sulphur, but given the rapid rate of economical development in this region the situation may deteriorate quickly. Areas that are particularly at risk include the large cities, northern Vietnam, most of central Thailand, most of peninsular Malaysia, eastern Sumatra and parts of Java, all of which receive total-sulphur depositions in excess of 0.5 g S m(-2) yr(-1). Our model simulates sulphate in precipitation in accordance with measurements, but it has a tendency to overestimate atmospheric SO2. It remains to be investigated whether this is a problem in the model formulation or a result of unrepresentative sampling. An immediate continuation of this study should be performed with higher spatial resolution than the currently used 100 x 100 km(2). Other imperfections in this model study, which should be addressed in future work, include parameterised vertical transport in deep convective clouds, the influence of natural emissions (primarily from volcanoes) on the concentration and deposition of sulphuric species, and the year-to-year variability of the driving meteorological conditions. (C) 2001 Elsevier Science Ltd. All rights reserved.

  • 39.
    Engardt, Magnuz
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Simpson, David
    Schwikowski, Margit
    Granat, Lennart
    Deposition of sulphur and nitrogen in Europe 1900-2050. Model calculations and comparison to historical observations2017Inngår i: Tellus. Series B, Chemical and physical meteorology, ISSN 0280-6509, E-ISSN 1600-0889, Vol. 69, artikkel-id 1328945Artikkel i tidsskrift (Fagfellevurdert)
  • 40.
    Engardt, Magnuz
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Siniarovina, U
    Khairul, N I
    Leong, C P
    Country to country transport of anthropogenic sulphur in Southeast Asia2005Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 39, nr 28, s. 5137-5148Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The MATCH model-driven by archived meteorological data from the ECMWF-has been used to study the long-range transport of pollutants in Southeast Asia during the year 2000. We have specifically investigated the atmospheric export and import of anthropogenic sulphur between nine countries in Southeast Asia as well as the import to these countries from the boundaries of our model domain, from southern China, and from international shipping in the surrounding waters. Compared to the conditions at the mid-latitudes (Europe, North America and East Asia), we find less long-range transport in this part of the world. In all countries in the region (except those with very small area, i.e. Singapore and Brunei), did the major part of the domestic emissions (60-70%) fall down on the emitting country itself. The fraction of the countries own emissions contributing to the total, annually accumulated, national deposition varied from 10% for Laos-which is a country with small emissions neighbouring large emitters-to 80-90% in countries not surrounded by significant emitters (i.e. Thailand, Indonesia, Singapore and Brunei). Sensitivity tests were performed to explore the uncertainties in the model simulations and to investigate to what extent the current results could be used for source-receptor relationships in the future, when the magnitude and location of the emissions may be different. We found that the general feature-with relatively little long-range transport of sulphur-will not be altered, while the absolute magnitude of the deposition in areas downwind of large emitters could change considerably if certain model parameters, or the emission patterns are changed. This is particularly true in light of the seasonal variation of the deposition pathways. The atmospheric import of anthropogenic sulphur from specific countries can vary by an order of magnitude between different months. Incidentally, a decrease in import from one country during a certain period is often compensated by a roughly equal increase of the import from another country during the same time. (c) 2005 Elsevier Ltd. All rights reserved.

  • 41. Eriksson, Charlotta
    et al.
    Nilsson, Mats E.
    Willers, Saskia M.
    Gidhagen, Lars
    SMHI, Forskningsavdelningen, Luftmiljö.
    Bellander, Tom
    Pershagen, Goran
    Traffic noise and cardiovascular health in Sweden: The roadside study2012Inngår i: Noise & Health, ISSN 1463-1741, E-ISSN 1998-4030, Vol. 14, nr 59, s. 140-147Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Long-term exposure to traffic noise has been suggested to increase the risk of cardiovascular diseases (CVD). However, few studies have been performed in the general population and on railway noise. This study aimed to investigate the cardiovascular effects of living near noisy roads and railways. This cross-sectional study comprised 25,851 men and women, aged 18-80 years, who had resided in Sweden for at least 5 years. All subjects participated in a National Environmental Health Survey, performed in 2007, in which they reported on health, annoyance reactions and environmental factors. Questionnaire data on self-reported doctors diagnosis of hypertension and/or CVD were used as outcomes. Exposure was assessed as Traffic Load (millions of vehicle kilometres per year) within 500 m around each participants residential address. For a sub-population (n = 2498), we also assessed road traffic and railway noise in L den at the dwelling facade. Multiple logistic regression models were used to assess Prevalence Odds Ratios (POR) and 95 Confidence Intervals (CI). No statistically significant associations were found between Traffic Load and self-reported hypertension or CVD. In the sub-population, there was no association between road traffic noise and the outcomes; however, an increased risk of CVD was suggested among subjects exposed to railway noise >= 50 dB(A); POR 1.55 (95 CI 1.00-2.40). Neither Traffic Load nor road traffic noise was, in this study, associated with self-reported cardiovascular outcomes. However, there was a borderline-significant association between railway noise and CVD. The lack of association for road traffic may be due to methodological limitations.

  • 42. Fang, Xin
    et al.
    Hu, Min
    Shang, Dongjie
    Tang, Rongzhi
    Shi, Linlin
    Olenius, Tinja
    SMHI, Forskningsavdelningen, Luftmiljö.
    Wang, Yujue
    Wang, Hui
    Zhang, Zijing
    Chen, Shiyi
    Yu, Xuena
    Zhu, Wenfei
    Lou, Shengrong
    Ma, Yan
    Li, Xin
    Zeng, Limin
    Wu, Zhijun
    Zheng, Jun
    Guo, Song
    Observational Evidence for the Involvement of Dicarboxylic Acids in Particle Nucleation2020Inngår i: Environmental Science and Technology Letters, E-ISSN 2328-8930, Vol. 7, nr 6, s. 388-394Artikkel i tidsskrift (Fagfellevurdert)
  • 43. Felipe Franco, Juan
    et al.
    Gidhagen, Lars
    SMHI, Forskningsavdelningen, Luftmiljö.
    Morales, Ricardo
    Behrentz, Eduardo
    Towards a better understanding of urban air quality management capabilities in Latin America2019Inngår i: Environmental Science and Policy, ISSN 1462-9011, E-ISSN 1873-6416, Vol. 102, s. 43-53Artikkel i tidsskrift (Fagfellevurdert)
  • 44. Felix, Erika
    et al.
    Gidhagen, Lars
    SMHI, Forskningsavdelningen, Luftmiljö.
    Alonso, Marcelo F.
    Nahirny, Everaldo P.
    Alves, Bruno L.
    Segersson, David
    SMHI, Forskningsavdelningen, Luftmiljö.
    Amorim, Jorge Humberto
    SMHI, Forskningsavdelningen, Luftmiljö.
    Passive sampling as a feasible tool for mapping and model evaluation of the spatial distribution of nitrogen oxides in the city of Curitiba, Brazil2019Inngår i: Air quality, atmosphere and health, ISSN 1873-9318, E-ISSN 1873-9326, Vol. 12, nr 7, s. 837-846Artikkel i tidsskrift (Fagfellevurdert)
  • 45.
    Foltescu, Valentin
    et al.
    SMHI.
    Pryor, S C
    Bennet, Cecilia
    SMHI, Forskningsavdelningen, Luftmiljö.
    Sea salt generation, dispersion and removal on the regional scale2005Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 39, nr 11, s. 2123-2133Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The MATCH (Multi-scale Atmospheric Transport and Chemistry) modelling system has been used as the modelling platform for regional-scale sea salt simulations. A new model version for sea salt aerosols has been constructed and assessed. This study presents the model concept and shows that the model is capable of simulating sea salt on a regional scale. The model agrees well with observations, particularly in terms of the sea salt mass concentrations at certain locations in Northern Europe. The observed wet fluxes are generally under-predicted due in part to systematic under-prediction of precipitation by the meteorological model used to drive MATCH. (c) 2005 Elsevier Ltd. All rights reserved.

  • 46. Gallardo, L
    et al.
    Olivares, G
    Langner, Joakim
    SMHI, Forskningsavdelningen, Luftmiljö.
    Aarhus Andrae, Bodil
    SMHI, Samhälle och säkerhet.
    Coastal lows and sulfur air pollution in Central Chile2002Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 36, nr 23, s. 3829-3841Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Air pollutants in Santiago (33.5degreesS, 70.8degreesW, 500m a.s.l.), a city with 5 million inhabitants, located in a basin in Central Chile surrounded by the high Andes, frequently exceed air quality standards. This affects human health and it stresses vegetation. The most extreme winter and fall pollution events occur when the subsident regime of the Pacific high is further enhanced by coastal lows (CLs), which bring down the base of the subsidence inversion. Under these conditions, the air quality worsens significantly giving rise to acute air pollution episodes. We assess the ability of a regional transport/chemistry/deposition model (MATCH) coupled to a meteorological model (High Resolution Limited Area Model-HIRLAM) to simulate the evolution of oxidized sulfur (SOx) in connection with intensive CLs. We focus on SOx since it is an environmental issue of concern, and the emissions and concentrations of SOx have been regularly monitored making it easier to bracket model outputs for SOx than for other pollutants. Furthermore, the SOx emissions in the area are very large, i.e., about 0.4% of the global anthropogenic sources. Comparisons with observations indicate that the combination of HIRLAM and MATCH is a suitable tool for describing the regional patterns of dispersion associated with CLs. However, the low number and the limited geographical coverage of reliable air quality data preclude a complete evaluation of the model. Nevertheless, we show evidence of an enhanced contribution of the largest copper smelter in the area, i.e., Caletones, to the burden of SOx in the Santiago basin, especially in the form of sulfate associated to fine particles (diameters < 2.5 mum), during CLs. Further, we speculate that the Caletones plume may trigger or promote secondary aerosol formation during CLs in the Santiago basin. (C) 2002 Elsevier Science Ltd. All rights reserved.

  • 47. Geels, Camilla
    et al.
    Andersson, Camilla
    SMHI, Forskningsavdelningen, Luftmiljö.
    Hanninen, Otto
    Lanso, Anne Sofie
    Schwarze, Per E.
    Skjoth, Carsten Ambelas
    Brandt, Jorgen
    Future Premature Mortality Due to O-3, Secondary Inorganic Aerosols and Primary PM in Europe - Sensitivity to Changes in Climate, Anthropogenic Emissions, Population and Building Stock2015Inngår i: International Journal of Environmental Research and Public Health, ISSN 1661-7827, E-ISSN 1660-4601, Vol. 12, nr 3, s. 2837-2869Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Air pollution is an important environmental factor associated with health impacts in Europe and considerable resources are used to reduce exposure to air pollution through emission reductions. These reductions will have non-linear effects on exposure due, e.g., to interactions between climate and atmospheric chemistry. By using an integrated assessment model, we quantify the effect of changes in climate, emissions and population demography on exposure and health impacts in Europe. The sensitivity to the changes is assessed by investigating the differences between the decades 2000-2009, 2050-2059 and 2080-2089. We focus on the number of premature deaths related to atmospheric ozone, Secondary Inorganic Aerosols and primary PM. For the Nordic region we furthermore include a projection on how population exposure might develop due to changes in building stock with increased energy efficiency. Reductions in emissions cause a large significant decrease in mortality, while climate effects on chemistry and emissions only affects premature mortality by a few percent. Changes in population demography lead to a larger relative increase in chronic mortality than the relative increase in population. Finally, the projected changes in building stock and infiltration rates in the Nordic indicate that this factor may be very important for assessments of population exposure in the future.

    Fulltekst (pdf)
    fulltext
  • 48.
    Gidhagen, Lars
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    Lovenheim, Boel
    Johansson, Christer
    Modeling Effects of Climate Change on Air Quality and Population Exposure in Urban Planning Scenarios2012Inngår i: Advances in Meteorology, ISSN 1687-9309, E-ISSN 1687-9317, artikkel-id 240894Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We employ a nested system of global and regional climate models, linked to regional and urban air quality chemical transport models utilizing detailed inventories of present and future emissions, to study the relative impact of climate change and changing air pollutant emissions on air quality and population exposure in Stockholm, Sweden. We show that climate change only marginally affects air quality over the 20-year period studied. An exposure assessment reveals that the population of Stockholm can expect considerably lower NO2 exposure in the future, mainly due to reduced local NOx emissions. Ozone exposure will decrease only slightly, due to a combination of increased concentrations in the city centre and decreasing concentrations in the suburban areas. The increase in ozone concentration is a consequence of decreased local NOx emissions, which reduces the titration of the long-range transported ozone. Finally, we evaluate the consequences of a planned road transit project on future air quality in Stockholm. The construction of a very large bypass road (including one of the largest motorway road tunnels in Europe) will only marginally influence total population exposure, this since the improved air quality in the city centre will be complemented by deteriorated air quality in suburban, residential areas.

  • 49.
    Gidhagen, Lars
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Johansson, C
    Langner, Joakim
    SMHI, Forskningsavdelningen, Luftmiljö.
    Foltescu, Valter
    SMHI.
    Urban scale modeling of particle number concentration in Stockholm2005Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 39, nr 9, s. 1711-1725Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A three-dimensional dispersion model has been implemented over the urban area of Stockholm (35 x 35 km) to assess the spatial distribution of number concentrations of particles in the diameter range 3-400 nm. Typical number concentrations in the urban background of Stockholm is 10 000 cm(-3), while they are three times higher close to a major highway outside the city and seven times higher within a densely trafficked street canyon site in the city center. The model, which includes an aerosol module for calculating the particle number losses due to coagulation and dry deposition, has been run for a 10-day period. Model results compare well with measured data, both in levels and in temporal variability. Coagulation was found to be of little importance in terms of time averaged concentrations, contributing to losses of only a few percent as compared to inert particles, while dry deposition yield particle number losses of up to 25% in certain locations. Episodic losses of up to 10% due to coagulation and 50% due to deposition, are found some kilometers downwind of major roads, rising in connection with low wind speed and suppressed turbulent mixing. Removal due to coagulation and deposition will thus be more significant for the simulation of extreme particle number concentrations during peak episodes. The study shows that dispersion models with proper aerosol dynamics included may be used to assess particle number concentrations in Stockholm, where ultrafine particles principally originate from traffic emissions. Emission factors may be determined from roadside measurements, but ambient temperature must be considered, as it has a strong influence on particle number emissions from vehicles. (c) 2005 Elsevier Ltd. All rights reserved.

  • 50.
    Gidhagen, Lars
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Johansson, C
    Langner, Joakim
    SMHI, Forskningsavdelningen, Luftmiljö.
    Olivares, G
    Simulation of NOx and ultrafine particles in a street canyon in Stockholm, Sweden2004Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 38, nr 14, s. 2029-2044Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A computational fluid dynamic (CFD) model has been used to assess the concentrations of NO, and particle number in a street canyon in Stockholm with a high traffic volume. Comparisons of a simulated 11-week long time series of NOx with measurements (both sides of the street, urban background excluded) show good agreement, especially if emissions are distributed to be three times higher along the side of the street where the traffic is uphill, as compared to the downhill side. The simulation of number concentrations of inert particles indicates a similar asymmetry in emissions. A month-long measurement of particle size distribution (7-450 nm) at street level indicates that the ratio of nucleation size mode particle (7-20 nm) to total particle number (7-450 nm) is decreasing for increased particle surface area. Given the strong dominance of the locally generated particles over the urban background, this is interpreted as a local change in the size distribution. The results of a monodisperse aerosol dynamic model, coupled to the CFD model that simulates also the turbulence generated by vehicle movements, show that coagulation and deposition may reduce total particle inside the canyon with approximately 30% during low wind speeds. Most of the removal occurs shortly after emission, before the particles reach the leeward curb-side. Losses between the leeward curb-side and other locations in the street, e.g. roof levels, is estimated to be smaller, less than 10%. Coagulation is the dominating removal process under low wind speed conditions and deposition for higher wind speeds, the summed removal being smaller for high wind velocities. Deposition is enhanced over the road surface due to the velocities generated by vehicle movements. Although coagulation and deposition removal is most effective on the smallest ultrafine particles, this effect is not sufficient to explain the observed change in size distribution. It is suggested that also the formation of particles in the exhaust plumes is influenced by a larger particle surface area in the ambient air. (C) 2004 Elsevier Ltd. All rights reserved.

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