Change search
Refine search result
1 - 47 of 47
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Bringfelt, Björn
    et al.
    SMHI.
    Backström, Hans
    SMHI, Professional Services.
    Kindell, Sven
    SMHI, Professional Services.
    Omstedt, Gunnar
    SMHI, Research Department, Air quality.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Ullerstig, Anders
    SMHI, Research Department, Climate research - Rossby Centre.
    Calculations of PM-10 concentrations in Swedish cities - Modelling of inhalable particles1997Report (Other academic)
  • 2. De Geer, Lars-Erik
    et al.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Rodhe, Henning
    A Nuclear Jet at Chernobyl Around 21:23:45 UTC on April 25, 19862018In: Nuclear Technology, ISSN 0029-5450, E-ISSN 1943-7471, Vol. 201, no 1, p. 11-22Article in journal (Refereed)
  • 3.
    Foltescu, Valentin
    et al.
    SMHI, Research Department, Air quality.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Beräkning av moln- och dimdepositionen i Sverigemodellen – Resultat för 1997 och 1998: Estimation of cloud and fog deposition by use of ”Sverigemodellen” – Results for 1997 and 19982001Report (Other academic)
    Abstract [en]

    The capture of cloud and fog droplets by vegetation as a possibly important deposition mechanism has been recognised lately after reports of increased forest decline with altitude. We are concerned with interception, impaction and stickiness of polluted cloud water and fog droplets to terrestrial surfaces, including forest canopies. This deposition is mediated by low-level clouds, in which parts of the terrain can be immersed, or by the presence of orographic and radiation fog. In this study the transport of cloud and fog droplets towards terrestrial surfaces is parameterised and the “occult” deposition (mediated by both clouds and fog) is calculated by a new approach, implemented in “Sverigemodellen” (MATCH-Sverige), a 3D Eulerian transport and dispersion model employed for making environmental assessments in Sweden.The model scheme is taking into account the mesoscale analysis (MESAN) of low-cloud coverage and cloud-base height, the visibility analysis, detailed topography information, land use, modelled atmospheric concentrations and the instantaneous deposition parameters for the investigated species (acidifying air pollutants: sulphate and oxidised/reduced nitrogen).The model scheme is validated by comparing with throughfall monitoring of sulphate deposition to coniferous forests at elevated sites in the Swedish mountains. It shows a rather good fit to the measurements, generally within 25%, which is deemed as encouraging. Discrepancies exist though and are subject of discussion. The percentage of occult deposition can be up to 115% of the sum of dry and wet deposition. Therefore we cannot ignore this contribution in the assessments of deposition of acidifying pollutants. The highest fluxes of cloud deposition are assigned to mountainous regions in Northern Sweden, while the highest fog deposition is calculated at a location in Jönköpings County, on the Sydsvenska höglandet.

  • 4.
    Fredriksson, Ulf
    et al.
    SMHI, Core Services.
    Persson, Christer
    SMHI, Research Department, Air quality.
    NOx- och NO2-beräkningar vid Vasaterminalen i Stockholm1985Report (Other academic)
  • 5.
    Fredriksson, Ulf
    et al.
    SMHI, Core Services.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Laurin, Sten
    SMHI.
    Helsingborgsluft1985Report (Other academic)
  • 6. Galmarini, S
    et al.
    Bianconi, R
    Klug, W
    Mikkelsen, T
    Addis, R
    Andronopoulos, S
    Astrup, P
    Baklanov, A
    Bartniki, J
    Bartzis, J C
    Bellasio, R
    Bompay, F
    Buckley, R
    Bouzom, M
    Champion, H
    D'Amours, R
    Davakis, E
    Eleveld, H
    Geertsema, G T
    Glaab, H
    Kolax, Michael
    SMHI, Research Department, Climate research - Rossby Centre.
    Ilvonen, M
    Manning, A
    Pechinger, U
    Persson, Christer
    SMHI, Research Department, Air quality.
    Polreich, E
    Potemski, S
    Prodanova, M
    Saltbones, J
    Slaper, H
    Sofiev, M A
    Syrakov, D
    Sorensen, J H
    Van der Auwera, L
    Valkama, I
    Zelazny, R
    Ensemble dispersion forecasting - Part I: concept, approach and indicators2004In: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 38, no 28, p. 4607-4617Article in journal (Refereed)
    Abstract [en]

    The paper presents an approach to the treatment and analysis of long-range transport and dispersion model forecasts. Long-range is intended here as the space scale of the order of few thousands of kilometers known also as continental scale. The method is called multi-model ensemble dispersion and is based on the simultaneous analysis of several model simulations by means of ad-hoc statistical treatments and parameters. The models considered in this study are operational long-range transport and dispersion models used to support decision making in various countries in case of accidental releases of harmful volatile substances, in particular radionuclides to the atmosphere. The ensemble dispersion approach and indicators provide a way to reduce several model results to few concise representations that include an estimate of the models' agreement in predicting a specific scenario. The parameters proposed are particularly suited for long-range transport and dispersion models although they can also be applied to short-range dispersion and weather fields. (C) 2004 Elsevier Ltd. All rights reserved.

  • 7.
    Häggkvist, Kenneth
    et al.
    SMHI, Professional Services.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Robertson, Lennart
    SMHI, Research Department, Air quality.
    Spridningsberäkningar rörande gasutsläpp från ett antal källor inom SSAB Luleå-verken1986Report (Other academic)
  • 8.
    Jansson, Anna
    et al.
    SMHI, Core Services.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Strandberg, Gustav
    SMHI, Research Department, Climate research - Rossby Centre.
    2D meso-scale re-analysis of precipitation, temperature and wind over Europe - ERAMESAN: Time period 1980-20042007Report (Other academic)
    Abstract [en]

    The need for long time series of gridded meteorological data with a fine spatial and temporal resolution has increased in recent years. The requirements for this type of gridded meteorological data fields arise from many different areas of the society, in connection to atmospheric environment studies of air quality and deposition and trends in these parameters, regional climate change, wind energy, hydrological studies etc. The aim of the present project is to investigate the possibility of producing historical, high quality and time consistent, meso-scale re analyses for the whole of Europe regarding precipitation, 2 m temperature and wind for at least 25 years back in time.The MESAN analysis system (Häggmark et al., 2000) at SMHI was chosen as a basis for the reanalysis and the system was adjusted to cover the whole of Europe. In order to find the most appropriate first guess fields to be used in the MESAN system, a pilot study was performed. ERA- 40 data from ECMWF was selected as best possible first guess fields for the re analysis. The performed re-analysis, which is denoted ERAMESAN, includes gridded data covering all Europe with a time resolution of 6 h and a spatial resolution of 0.1º (11 km) in a rotated latitude longitude coordinate system for the time-period 1980-2004. All analyses are archived in GRIB-format and stored on disc at SMHI. The dataset is also available within the EUMETNET optional programme Showcase EUROGRID.A partial validation for the years 1998-2000, using a cross validation procedure with independent observations (5.5% of the total amount of stations), shows an improvement in ERAMESAN compared to the ERA-40 data for all studied parameters with regard to root mean square deviation, mean absolute deviation and mean bias deviation for all seasons. The deviations are roughly of the order of 15% smaller compared to what is obtained from ERA-40. The frequency distribution of large precipitation amounts per day and high wind speeds are substantially better described in ERAMESAN compared to ERA-40. However, the tendency to underestimate the frequency of very large precipitation amounts or high wind speeds, compared to observations, can be seen also for ERAMESAN. It is important to be aware of this limitation when using ERAMESAN data for practical applications concerning evaluation of risks for extreme wind speeds or very large precipitation amounts or in e.g. wind energy studies.

  • 9.
    Kindbom, Karin
    et al.
    IVL Swedish Environmental Research Institute.
    Sjöberg, Karin
    IVL Swedish Environmental Research Institute.
    Munthe, John
    IVL Swedish Environmental Research Institute.
    Peterson, Kjell
    SMHI.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Roos, Elisabet
    SMHI.
    Bergström, Robert
    SMHI, Research Department, Air quality.
    Nationell miljöövervakning av luft- och nederbördskemi 19961998Report (Other academic)
  • 10.
    Kindbom, Karin
    et al.
    IVL Svenska Miljöinstitutet AB.
    Svensson, Annika
    IVL Svenska Miljöinstitutet AB.
    Sjöberg, Karin
    IVL Svenska Miljöinstitutet AB.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Nationell miljöövervakning av luft- och nederbördskemi 1997, 1998 och 19992001Report (Other academic)
    Abstract [en]

    Measurements of the composition of air and precipitation in background areas in Sweden during 1997, 1998 and 1999 are presented in the report. Results from two national networks, EMEP and the Swedish Precipitation Chemistry Network, both run by IVL Swedish Environmental Research Institute, are compiled and evaluated. Included in the presentation are also model calculations of dispersion and deposition of sulphur- and nitrogen compounds over Sweden. The modelling is based on monitoring results from 1997 and the calculations have been made using the MATCH-Sweden modelling system developed by SMHI, Swedish Meteorological and Hydrological Institute. The Swedish Environmental Protection Agency finances the activities. The monitoring programmes during the three years have included daily sampling of sulphur dioxide, nitrogen dioxide and particle bound sulphate in air at six stations 1997 and five stations 1998 and 1999. Daily measurements of soot, total-nitrate and total-ammonium have been performed at four stations. Monthly sampling of sulphur dioxide and nitrogen dioxide has been made at 12 stations 1997 and 1998 and at 13 stations 1999. Ozone concentrations in ground-level air have been monitored at six stations. Measurements of mercury in air have been performed at two stations regarding total gaseous mercury (TGM) and particle bound mercury. The measurements of sulphur and nitrogen compounds in air displayed a decreasing gradient from south to north. Generally, the higher concentrations of sulphur dioxide, sulphate, soot and nitrogen dioxide are found during winter, while high levels of ozone are registered during spring or early summer. The remaining compounds show a more uniform concentration during the seasons. The annual averages were comparable to, or lower, than previous years. The highest annual average air concentration of ground-level ozone was, as previous years, registered in Esrange. Ozone levels above 180 μg/m3 were not registered during the period. AOT40 values were on a comparable level with previous years, except for southern Sweden 1998 where AOT40 values were unusually low. Daily sampling of precipitation using a wet-only sampler has been made at one station and weekly sampling at three stations. At nearly 30 stations, monthly sampling using bulk-samplers was carried out. The precipitation samples were analysed with respect to pH, sulphate, nitrate, ammonium, chloride, calcium, magnesium, sodium and potassium. At four stations sampling of precipitation for analysis of heavy metals, total-mercury and methyl-mercury was made. The components in precipitation generally showed a decreasing gradient from south to north. The concentration of sulphate has decreased somewhat compared to previous years. The annual averages of pH showed higher values in northern Sweden than in the south. The pH values were slightly higher throughout the country than in earlier years. The concentrations in precipitation and the deposition of heavy metals and mercury generally showed lower values in northern and higher values in southern Sweden. The MATCH-Sweden model is a three-dimensional Eulerian atmospheric dispersion model, which is used for calculation of dispersion and deposition of air pollutants over Sweden. This model system also includes a method for data assimilation of measured concentrations in air and precipitation. In this report only some few examples of calculated annual mean concentrations and annual deposition maps for 1997 and 1998 are presented for sulphur, oxidised and reduced nitrogen. The MATCH-Sweden model has also been used to estimate air pollution budgets for Sweden for the years 1997 and 1998. The Swedish net import of air pollutants is substantial for sulphur and NHx-nitrogen. The Swedish contribution to deposition over Sweden is about 7 % for sulphur, 11 % for NOx-nitrogen and 20 % for NHxnitrogen. MATCH-Sweden results show somewhat larger deposition values than the EMEP model over Sweden for sulphur and NOx-nitrogen. For NHx-nitrogen the values are much larger, especially in Northern Sweden where the MATCH-Sweden values are 2-3 times larger than the EMEP model.

  • 11.
    Klein, Thomas
    et al.
    SMHI, Core Services.
    Bergström, Robert
    SMHI, Research Department, Air quality.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Parameterization of dry deposition in MATCH2002Report (Other academic)
    Abstract [en]

    The present report describes the calculation of dry deposition in the Multi scale Atmospheric Transport and Chemistry modeling system (MATCH) applied in environmental monitoring studies. For this type of applications dry deposition is parameterized by means of a resistance concept. Modeled dry deposition velocities for different surface types, a variety of meteorological conditions and several chemical species are presented. The deposition’s dependence on the individual partial resistances and their variation with the meteorological conditions are illustrated by means of time-series. The details of the resistance concept are discussed in a pedagogical way in order to both facilitate understanding and to point out different deposition paths.Sensitivity studies have been performed for the laminar sub-layer resistance of particles for which two different settings of resistance values are compared. The importance of SO2 and NO2 uptake by the stomata of plants and the deposition of SO2 to the external parts of plants have also been investigated by means of sensitivity studies. In addition, horizontal maps and monthly mean values of dry deposition velocities based on meteorological data for 1998 are presented.

  • 12. Kovalets, Ivan V.
    et al.
    Asker, Christian
    SMHI, Research Department, Air quality.
    Khalchenkov, Alexander V.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Lavrova, Tatyana V.
    Atmospheric dispersion of radon around uranium mill tailings of the former Pridneprovsky Chemical Plant in Ukraine2017In: Journal of Environmental Radioactivity, ISSN 0265-931X, E-ISSN 1879-1700, Vol. 172, p. 173-190Article in journal (Refereed)
  • 13. Kovalets, Ivan V.
    et al.
    Robertson, Lennart
    SMHI, Research Department, Air quality.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Didkivska, Svitlana N.
    Ievdin, Ievgen A.
    Trybushnyi, Dmytro
    Calculation of the far range atmospheric transport of radionuclides after the Fukushima accident with the atmospheric dispersion model MATCH of the JRODOS system2014In: International Journal of Environment and Pollution, ISSN 0957-4352, E-ISSN 1741-5101, Vol. 54, no 2-4, p. 101-109Article in journal (Refereed)
    Abstract [en]

    The paper presents estimates of the far-range atmospheric dispersion of radionuclides after the accident at Fukushima Daiichi Nuclear Power Plant (NPP), obtained using the long-range atmospheric dispersion model MATCH. Software tools were developed to run MATCH in the EU nuclear emergency response system JRODOS using freely available numerical weather prediction (NWP) data of the Global Forecasting System (GFS) operated by the United States National Center of Environmental Prediction (NCEP). Comparisons are made of results with JRODOS/MATCH and a standalone MATCH operated by Swedish Meteorological and Hydrological Institute (SMHI) driven by the European Center for Medium-Range Weather Forecasts (ECMWF) NWP data.

  • 14.
    Langner, Joakim
    et al.
    SMHI, Research Department, Air quality.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Robertson, Lennart
    SMHI, Research Department, Air quality.
    Concentration and deposition of acidifying air pollutants over Sweden: Estimates for 1991 based on the match model and observations1995In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 85, no 4, p. 2021-2026Article in journal (Refereed)
    Abstract [en]

    The MATCH (Mesoscale Atmospheric Transport and CHemistry) model has been developed as a tool for air pollution assessment studies on different geographical scales. MATCH is an Eulerian atmospheric dispersion model, including physical and chemical processes governing sources, atmospheric transport and sinks of oxidized sulfur and oxidized and reduced nitrogen. Using a combination of air and precipitation chemistry measurements and the MATCH model, the national and long-range transport contributions to air pollution and deposition can be quantified in the model region. The calculations for the year 1991 show that the Swedish import was about 4.5 times larger than the export for sulfur and about six times larger for reduced nitrogen, while the Swedish import of oxidized nitrogen only exceeded the export by 10%. Using the MATCH system we estimate the long-range transport in an independent way compared to EMEP. Comparison between the EMEP and MATCH calculations for 1991 show that the total deposition of oxidized nitrogen over Sweden is similar, while the EMEP-values for total deposition of oxidized sulfur and reduced nitrogen are 25% respectively 40% smaller than what is obtained from MATCH.

  • 15.
    Langner, Joakim
    et al.
    SMHI, Research Department, Air quality.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Robertson, Lennart
    SMHI, Research Department, Air quality.
    Ullerstig, Anders
    SMHI, Research Department, Climate research - Rossby Centre.
    Air pollution Assessment Study Using the MATCH Modelling System: Application to sulfur and nitrogen compounds over Sweden 19941996Report (Other academic)
  • 16.
    Langner, Joakim
    et al.
    SMHI, Research Department, Air quality.
    Robertson, Lennart
    SMHI, Research Department, Air quality.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Ullerstig, Anders
    SMHI, Research Department, Climate research - Rossby Centre.
    Validation of the operational emergency response model at the Swedish Meteorological and Hydrological Institute using data from ETEX and the Chernobyl accident1998In: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 32, no 24, p. 4325-4333Article in journal (Refereed)
    Abstract [en]

    The Eulerian atmospheric tracer transport model MATCH (Multiscale Atmospheric Transport and Chemistry model) has been extended with a Lagrangian particle model treating the initial dispersion of pollutants from point sources. The model has been implemented at the Swedish Meteorological and Hydrological Institute in an emergency response system for nuclear accidents and can be activated on short notice to provide forecast concentration and deposition fields. The model has been used to simulate the transport of the inert tracer released during the ETEX experiment and the transport and deposition of Cs-137 from the Chernobyl accident. Visual inspection of the results as well as statistical analysis shows that the extent, time of arrival and duration of the tracer cloud, is in good agreement with the observations for both cases, with a tendency towards over-prediction for the first ETEX release. For the Chernobyl case the simulated deposition pattern over Scandinavia and over Europe as a whole agrees with observations when observed precipitation is used in the simulation. When model calculated precipitation is used, the quality of the simulation is reduced significantly and the model fails to predict major features of the observed deposition held. (C) 1998 Elsevier Science Ltd. All rights reserved.

  • 17.
    Laurin, Sten
    et al.
    SMHI.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Beräknad formaldehydspridning och deposition från SWEDSPANs spånskivefabrik1985Report (Other academic)
  • 18.
    Lövblad, Gun
    et al.
    IVL Swedish Environmental Research Institute.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Background report on air pollution situation in the Baltic states - a prefeasibility study: IVL Publikation B 10381991Report (Other academic)
  • 19.
    Omstedt, Gunnar
    et al.
    SMHI, Research Department, Air quality.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Skagerström, M.
    SMHI.
    Vedeldning i småhusområden2003Report (Other academic)
  • 20.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Beräkning av lukt och föroreningshalter i luft runt Neste Polyester i Nol1987Report (Other academic)
  • 21.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Kvaliteten hos nederbördskemiska mätdata som utnyttjas för dataassimilation i "MATCH-Sverige modellen": Rapport till Naturvårdsverkets nationella miljöövervakning, delprogram Luft2002Report (Other academic)
    Abstract [sv]

    MATCH-Sverige modellen utnyttjas bl.a. för kartläggning av den totala föroreningsdepositionen över Sverige, samt för separata studier av Sveriges föroreningsbidrag och den långväga föroreningstransporten. I de beräkningarna ingår en dataassimilation av atmosfärkemiska mätdata i modellen. Det är viktigt att MATCH-Sverige beräkningarna är av god kvalitet, eftersom resultaten ligger till grund för en rad miljöstudier av olika slag i Sverige. Det ställer i sin tur krav på att de atmosfärkemiska mätdata, som utgör indata i dataassimilationen, också är av god kvalitet och att de utnyttjas på rätt sätt. I denna studie redovisas jämförelser och diskuteras osäkerheter av betydelse för dataassimilationen, främst rörande nederbördsmängder samt koncentrationer av svavel-, NOx-kväve och NHx-kväve i nederbörd.I de nationella svenska nederbördskemiska stationsnäten, EMEP och LoN (Luft och Nederbördskemiska stationsnätet) finns två platser, Bredkälen nordost om Östersund och Vavihill i centrala Skåne, med provtagare placerade omedelbart intill varandra vilka kan jämföras dels inbördes, dels med oberoende data från MATCH-Sverige. Jämförelserna mellan EMEP och LoN stationerna, vad gäller uppmätta nederbördsmängder månadsvis, visar relativt dålig samvariation. För år 2000 är samvariationen mellan uppmätta nederbördsmängder i Vavihill t.o.m. mycket dålig. Därmed finns stor risk för att också de uppmätta halterna i nederbörd vid åtminstone en av stationerna är av bristande kvalitet. Görs jämförelser mellan de uppmätta nederbördsmängderna, EMEP och LoN var för sig, och de nederbördsmängder som utnyttjas i MATCH-Sverige och som bygger på SMHI:s hela stationsnät, fås bättre samvariation. Den förklarade variansen som erhålles vid dessa jämförelser är dock avsevärt lägre än vad som fås då närbelägna meteorologiska stationer i SMHI:s stationsnät jämförs.Vid LoN-stationerna (Bredkälen och Vavihill) faller år 2000 ca 70% av sulfat och nitratvärdena inom plus/minus 30% av EMEP-stationens halt men bara ca 25% ammoniumvärdena. De allra flesta av de LoN-halter som faller utanför intervallet är större än 1.3 gånger EMEP-halten. Förhållandena är likartade vid de båda LoN-stationerna. Detta överensstämmer inte med resultaten i Granat (1988), som visade på mycket små skillnader i uppmätta halter mellan "bulk" provtagare (vid LoN-stationerna) och "lock" provtagare (vid EMEP-stationerna). Den bristande överensstämmelsen i nederbördskemiska mätdata mellan stationer som ligger omedelbart intill varandra bör undersökas ytterligare och åtgärder vidtas för att om möjligt förbättra situationen. En sådan åtgärd bör vara att förbättra insamlingen av nederbörd så att uppmätta nederbördsmängder kan erhålls med ungefär samma kvalitet som för rent meteorologiska stationer, även om provtagningsperioderna är längre för de nederbördskemiska stationerna. För är få resultat av god kvalitet från MATCH-Sverige modellen är det betydligt bättre med ett mindre antal atmosfärkemiska mätstationer av hög kvalitet, än ett stort antal stationer med varierande - och okänd - kvalitet. Speciellt viktigt är detta för studier av trender. (Se även Persson m.fl., 1996).

  • 22.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Local scale plume model for nitrogen oxides. Verification1986Report (Other academic)
  • 23.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Bergström, Robert
    SMHI, Research Department, Air quality.
    Atmospheric Transport Model Studies for Sweden – Comparison to EMEP Model Results and Evaluation of Precipitation Chemistry Station Networks2001In: Air Pollution Modeling and Its Application XIV / [ed] Sven-Erik Gryning, Francis A. Schiermeier, Springer, 2001, p. 165-172Chapter in book (Other academic)
  • 24.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Funquist, Lennart
    SMHI, Research Department, Oceanography.
    Local scale plume model for nitrogen oxides: Model description1984Report (Other academic)
  • 25.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Langner, Joakim
    SMHI, Research Department, Air quality.
    Robertson, Lennart
    SMHI, Research Department, Air quality.
    Regional spridningsmodell för Göteborgs och Bohus, Hallands och Älvsborgs län: A mesoscale air pollution dispersion model for the Swedish west-coast region. In Swedish with captions also in English1994Report (Other academic)
  • 26.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Magnusson, Mikael
    SMHI, Core Services.
    Kvaliteten i uppmätta nederbördsmängder inom svenska nederbördskemiska stationsnät2003Report (Other academic)
    Abstract [en]

    High quality measurements of precipitation amounts in precipitation chemistry networks are of large importance in order to obtain correct information concerning concentrations in precipitation as well as wet deposition of air pollutants. In this study the quality of measured precipitation amounts at each of three different Swedish precipitation chemistry networks has been investigated. For shorter periods during 1998-2001 quality deficiencies were found at two Swedish EMEP stations. The reason to that seems to be technical problems with the lid samplers used at that network. For the Swedish air and precipitation chemistry network (PMK) and the regional network (REG) deficiencies in precipitation measurements were found for the winter seasons. Very large scatter in precipitation amounts was obtained when comparisons were made with objective interpolated precipitation fields based on all SMHI observations. The reason to this disagreement is assumed to be the use of “snowsacks” on the samplers during the winter half-year regardless of weather condition. These “snow-sacks” are assumed to influence the aerodynamic conditions around the samplers and thus also influence the efficiency in sampling raindrops and snowflakes.

  • 27.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Omstedt, Gunnar
    SMHI, Research Department, Air quality.
    En modell för beräkning av luftföroreningars spridning och deposition på mesoskala1980Report (Other academic)
    Abstract [sv]

    Mängden föroreningar, som förs till atmosfären, har under de senaste trettio åren kraftigt ökats. Deposition av dessa till marken leder till en rad biologiska effekter. Risker för skador på olika ekosystem genom deposition av tex tungmetaller och syra har därför alltmer börjat diskuteras som viktiga lokaliseringskriterier för fossileldade kraftverk och vissa större industrier. Depositionen av bly i omedelbar närhet av livligt trafikerade motorleder är ett annat exempel där negativa miljöeffekter befaras.

    Uppställandet av effektrelaterade utsläppskriterier medför ett behov av redskap för att kunna göra kvantitativa uppskattningar av förväntade depositioner i omgivningen av en källa. För kraftverk kan behovet av information om depositionsfördelningen, som underlag för lokaliseringsbeslut, röra ett område med flera hundra kilometers utsträckning.

    Vid studier av den lokala spridningen runt en punktkälla har under lång tid den gaussiska plymmodellen varit allmänt använd. Den utgör ett enkelt och i många fall mycket bra hjälpmedel, men har avsevärda begränsningar i de fall då depositionsprocesser och kemiska omvandlingar måste inkluderas i beräkningarna. I modeller baserade på diffusionsekvationen, där vissa antaganden om den turbulenta diffusiviteten görs (sk K-teori), finns möjlighet att på ett väsentligt mer realistiskt sätt inkludera processer som rör deposition och kemiska omvandlingar. Nackdelen är dock att den matematiska behandlingen blir mer komplicerad.

    Numeriska lösningar av diffusionsekvationen har använts av tex Bo in & Persson (1975) och Omstedt & Rodhe (1977). I båda fallen gällde tillämpningarna föroreningsspridning på storregional skala. Maul (1977) har presenterat en analytisk lösning, som tillämpats på föroreningsspridning på mesoskala. Svårigheterna vid tillämpningen av K-teorin är framförallt att bestämma riktiga värden på de ingångsparametrar som fordras. För analytiska lösningar finns dessutom matematiska hinder för godtyckliga vind- och diffusivitetsprofiler. Detta har resulterat i att beräkningar med K-modeller hittills huvudsakligen utförts för några enkla medelprofiler.

    Avsikten med föreliggande projekt har varit att utveckla en för praktiskt brukanvändbar spridningsmodell för studier av torr- och våtdepositionen av föroreningar på lokal- och mesoskala, där godtyckliga vind- och diffusivitetsprofiler kan användas. Dessa genereras med hjälp av en gränsskiktsmodell för olika vädersituationer.

  • 28.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Ressner, Elisabet
    SMHI.
    Klein, Thomas
    SMHI, Core Services.
    Nationell miljöövervakning – MATCH-Sverige modellen: Metod- och resultatsammanställning för åren 1999-2002 samt diskussionav osäkerheter, trender och miljömål2004Report (Other academic)
    Abstract [en]

    National air pollution assessments based on the MATCH-Sweden model – Results for the period 1999-2002 The MATCH-Sweden model system is used as a tool for mapping of air pollution deposition and concentration over Sweden and for air pollution assessment studies.The system includes a simplified type of data assimilation of backgroundatmospheric chemistry observations in Sweden and Norway. Over the entire period 1999-2002 the annual sulphur and nitrogen deposition consistently shows a maximum over Southwest Götaland and decreases northwards. An annual air pollution budget for Sweden is determined. During the period of study the Swedish emissions account for 5-7% of the total annual deposition of sulphur in Sweden and for 11-13% of the corresponding NOx-deposition. The Swedish contribution to the total deposition of NHx-nitrogen is, according to the present calculations, about 16%. However, the uncertainty in this value is larger than for sulphur and NOx-nitrogen.Comparisons between results for the year 2000 obtained with MATCH-Sweden and the new “Unified EMEP Eulerian model” (EMEP, 2003) respectively, show good agreement for most parameters. The agreement is much better than observed in earlier comparisons with the old EMEP model. Large differences are found only for long-range transport contribution to the NHx-deposition over Northern Sweden, where MATCH-Sweden calculations indicate larger depositions than EMEP. However, the MATCH-Sweden system – including simplified data assimilation - suffers from a lack of representative air and precipitation NHx-measurements in that area. A tentative estimate of deposition trends over Sweden indicates a 50-55% decrease for sulphur between 1991 and 2002. For NOx- and NHx-nitrogen the corresponding decrease in deposition is only about 15%each.

  • 29.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Robertson, Lennart
    SMHI, Research Department, Air quality.
    Spridnings- och depositionsberäkningar för en sopförbränningsanläggning i Skövde1986Report (Other academic)
  • 30.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Robertson, Lennart
    SMHI, Research Department, Air quality.
    Spridningsberäkningar rörande gasutsläpp vid ScanDust i Landskrona - bestämning av cyanväte1987Report (Other academic)
  • 31.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Robertson, Lennart
    SMHI, Research Department, Air quality.
    Grennfelt, P.
    IVL.
    Kindbom, K.
    IVL.
    Lövblad, Gun
    IVL Swedish Environmental Research Institute.
    Svanberg, P-A
    IVL.
    Luftföroreningsepisoden över södra Sverige 2–4 februari 19871987Report (Other academic)
  • 32.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Robertson, Lennart
    SMHI, Research Department, Air quality.
    Häggkvist, Kenneth
    SMHI, Professional Services.
    Spridningsberäkningar, SSAB - Luleå-verken1986Report (Other academic)
    Abstract [sv]

    Spridningsberäkningar har utförts för ett par större utsläpp, av haveri­karaktär, från en större masugnsklocka. Utsläppen avser relativt stora gasflöden (20 000 m3 respektive 50 000 m3 ) under kort tid (5 respektive 15 min) och studien har syftat till att bestämma halter av CO och H2S i omgivningen samt områden där risk för explosion kan förekomma. Nedan ges en sammanfattande redovisning av resultaten. Av tabell 1 ( sid 2) framgår hur utsläppen specificerats, och de i tabellen angivna beteckning­arna för respektive fall utnyttjas i sammanfattningen nedan.

  • 33.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Robertson, Lennart
    SMHI, Research Department, Air quality.
    Thaning, Lennart
    FOA.
    Model for Simulation of Air and Ground Contamination Associated with Nuclear Weapons. An Emergency Preparedness Model2000Report (Other academic)
  • 34.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Rodhe, H.
    MISU.
    De Geer, L-E
    FOA.
    The Chernobyl accident – A meteorological analysis of how radionucleides reached Sweden1986Report (Other academic)
  • 35.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    RODHE, H
    DE GEER, LE
    THE CHERNOBYL ACCIDENT - A METEOROLOGICAL ANALYSIS OF HOW RADIONUCLIDES REACHED AND WERE DEPOSITED IN SWEDEN1987In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 16, no 1, p. 20-31Article in journal (Refereed)
  • 36.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Rodhe, H.
    MISU.
    De Geer, L-E.
    FOA.
    Tjernobylolyckan - En meteorologisk analys av hur radioaktivitet spreds till Sverige1986Report (Other academic)
  • 37.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Ullerstig, Anders
    SMHI, Research Department, Climate research - Rossby Centre.
    Model calculations of dispersion of lindane over Europe: Pilot study with comparisons to easurements around the Baltic Sea and the Kattegat1996Report (Other academic)
  • 38.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Ullerstig, Anders
    SMHI, Research Department, Climate research - Rossby Centre.
    Regional luftmiljöanalys för Västmanlands län baserad på MATCH modell-beräkningar och mätdata: Analys av 1994 års data1997Report (Other academic)
  • 39.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Ullerstig, Anders
    SMHI, Research Department, Climate research - Rossby Centre.
    Robertson, Lennart
    SMHI, Research Department, Air quality.
    Kindbom, Karin
    IVL Swedish Environmental Research Institute.
    Sjöberg, Karin
    IVL Swedish Environmental Research Institute.
    The Swedish Precipitation Chemistry Network: Studies in network design usting the MATCH modelling system and statistical methods1996Report (Other academic)
  • 40.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Wern, Lennart
    SMHI, Core Services.
    Beräkningar av svaveldepositionen i Stockholmsområdet1986Report (Other academic)
  • 41.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Wern, Lennart
    SMHI, Core Services.
    Luftvårdsstudie avseende industrikombinatet i Nynäshamn - depositionsberäkningar av koldamm1985Report (Other academic)
  • 42.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Wern, Lennart
    SMHI, Core Services.
    Spridnings- och depositionsberäkningar för avfalls- förbränningsanläggningar i Sofielund och Högdalen1985Report (Other academic)
  • 43.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Wern, Lennart
    SMHI, Core Services.
    Spridnings- och depositionsberäkningar för avfallsförbränningsanläggning i Högdalen1985Report (Other academic)
  • 44.
    Persson, Christer
    et al.
    SMHI, Research Department, Air quality.
    Wern, Lennart
    SMHI, Core Services.
    Spridnings- och depositionsberäkningar för avfallsförbränningsanläggning i Sofielund1985Report (Other academic)
  • 45. Potempski, S.
    et al.
    Galmarini, S.
    Addis, R.
    Astrup, P.
    Bader, S.
    Bellasio, R.
    Bianconi, R.
    Bonnardot, F.
    Buckley, R.
    D'Amours, R.
    van Dijk, A.
    Geertsema, G.
    Jones, A.
    Kaufmann, P.
    Pechinger, U.
    Persson, Christer
    SMHI, Research Department, Air quality.
    Polreich, E.
    Prodanova, M.
    Robertson, Lennart
    SMHI, Research Department, Air quality.
    Sorensen, J.
    Syrakov, D.
    Multi-model ensemble analysis of the ETEX-2 experiment2008In: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 42, no 31, p. 7250-7265Article in journal (Refereed)
    Abstract [en]

    In this paper we investigate the results of multi-model simulations performed on the ETEX-2 experiment by the ENSEMBLE modelling community. New sets of results were created by taking different percentiles of the distribution of the models' predicted values. Both single models and the new constructed sets of results have been compared with the observed data. While a similar comparison for the ETEX-1 case indicated the median model was superior to any single model, for the ETEX-2 case, the situation is more difficult due to complex meteorological conditions, and no absolute and clear conclusions can be obtained. However, for emergency response purposes the median model still can be considered the most viable option also for complicated meteorological situation such is the ETEX-2 experiment. (c) 2008 Elsevier Ltd. All rights reserved.

  • 46.
    Robertson, Lennart
    et al.
    SMHI, Research Department, Air quality.
    Persson, Christer
    SMHI, Research Department, Air quality.
    ATTEMPTS TO APPLY 4-DIMENSIONAL DATA ASSIMILATION OF RADIOLOGICAL DATA USING THE ADJOINT TECHNIQUE1993In: Radiation Protection Dosimetry, ISSN 0144-8420, E-ISSN 1742-3406, Vol. 50, no 2-4, p. 333-337Article in journal (Refereed)
    Abstract [en]

    A data assimilation procedure is presented. By feeding measurements into a dispersion model. using the adjoint technique, it is shown that the proper transport level as well as the source intensity can he found. The technique is tested on a fictitious accidental release. and thus fictitious measurements are used.

  • 47.
    Thomas, Manu
    et al.
    SMHI, Research Department, Air quality.
    Brannstrom, Niklas
    Persson, Christer
    SMHI, Professional Services.
    Grahn, Hakan
    von Schoenberg, Pontus
    Robertson, Lennart
    SMHI, Research Department, Air quality.
    Surface air quality implications of volcanic injection heights2017In: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 166, p. 510-518Article in journal (Refereed)
1 - 47 of 47
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
v. 2.35.8
|