| 1. |
- Klingberg, Jenny, 1978, et al.
(author)
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Observed annual surface ozone maxima and minima in northern and central Europe from 1990–2015 — latitude dependence and temporal trends
- 2019
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In: Boreal environment research. - 1239-6095. ; 24, s. 201-214
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Journal article (peer-reviewed)abstract
- Ground-level ozone is an air pollutant that, despite reductions in precursor emission in Europe, still represents a risk to vegetation and human health. This study is based on observations of ozone concentrations ([O3]) from 25 European monitoring stations, north of the Alps within the EMEP network, during the 26-year period from 1990–2015. We analyzed the maximum and minimum hourly [O3] as well as the seasonal cycle in relation to latitude. In addition, temporal trends were studied. The maximum [O3] increased towards the south of the study area, while the yearly minimum of daytime mean increased towards the north. There was a strong correlation between the day of year when the maximum [O3] occurred and latitude: the maximum [O3] occurred earlier in the north. The maximum daytime [O3] decreased at all stations while the minimum daytime [O3] increased at most stations during the studied time period.
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| 2. |
- Mills, Gina, 1959, et al.
(author)
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New stomatal flux-based critical levels for ozone effects on vegetation
- 2011
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In: Atmospheric Environment. - : Elsevier BV. - 1873-2844 .- 1352-2310. ; 45:28, s. 5064-5068
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Journal article (peer-reviewed)abstract
- The critical levels for ozone effects on vegetation have been reviewed and revised by the LRTAP Convention. Eight new or revised critical levels based on the accumulated stomatal flux of ozone (POD gamma, the Phytotoxic Ozone Dose above a threshold flux of Y nmol m(-2) PLA s(-1), where PLA is the projected leaf area) have been agreed. For each receptor, data were combined from experiments conducted under naturally fluctuating environmental conditions in 2-4 countries, resulting in linear dose response relationships with response variables specific to each receptor (r(2) = 0.49-0.87, p
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| 3. |
- Pihl Karlsson, G, et al.
(author)
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Marknära ozon i bakgrundsmiljö i södra Sverige - Ozonmätnätet i södra Sverige 2020
- 2021
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Reports (other academic/artistic)abstract
- Huvudsyftet med mätningarna inom ”Ozonmätnätet i södra Sverige” är att ge en regional uppskattning av eventuella överskridanden av de ozonindex som beskriver inverkan av marknära ozon på äxtligheten (AOT40). ”Ozonmätnätet i södra Sverige” bidrar även till den nationella övervakningen av ozonhalterna, då programmet ger mer detaljerad information av ozonvariationen i södra Sverige. Ozonindex beräknas utifrån resultaten från enkla och kostnadseffektiva mätningar av ozonhalter med diffusions-provtagare på månadsbasis, i kombination med timvisa mätningar av lufttemperaturer. Temperaturmätningarna används som ett mått på variationen i luftens stabilitet under dygnet, vilket i sin tur ger ett mått på variationen i ozonkoncentration under dygnet. Utifrån resultaten från mätningarna görs skattningar av AOT40. Förekomsten av marknära ozon beror på utsläpp av ozonbildande ämnen lokalt, regionalt, nationellt och globalt. Ozonhalterna i ett område varierar bland annat beroende på områdets topografi (höglänt eller låglänt) samt dess avstånd från havet. Tillsammans påverkar dessa regionala omständigheter den lokala ozonförekomsten. Detta ligger till grund för den geografiska uppdelning i fem olika zoner i Sverige som görs inom detta mätprogram. Uppdelningen baseras främst på geografisk position i nord-sydlig och öst-västlig riktning. Ozonhalterna vid olika närliggande platser kan skilja sig åt relativt mycket, därför har varje zon även delats in i tre lokaltyper (höglänta, kustnära eller låglänta).
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| 4. |
- Piikki, Kristin, et al.
(author)
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Estimates of AOT ozone indices from time-integrated ozone data and hourly air temperature measurements in southwest Sweden
- 2009
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In: Environmental Pollution. - : Elsevier. - 0269-7491 .- 1873-6424. ; 157:11, s. 3051-3058
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Journal article (peer-reviewed)abstract
- Surface ozone concentration and surface air temperature was measured hourly at three coastal sites, four low elevation inland sites and two high elevation inland sites in southwestern Sweden. Diurnal ozone concentration range (DOR) and diurnal temperature range (DTR) were strongly correlated, both spatially and temporally, most likely because both depended on atmospheric stability. Accumulated ozone exposure above a threshold concentration of x nmol mol(-1) (AOTx) was estimated from time-integrated ozone concentration (as from diffusive sampling) and measures of ozone concentration variability. Two methods both estimated 24-h AOTx with high accuracy (modelling efficiencies >90% for x <= 40 nmol mol(-1)). Daytime (08:00-20:00) AOTx could not be equally well estimated. Estimates were better for lower AOT thresholds. Diffusive ozone concentration sampling, combined with hourly temperature monitoring, could be a valuable complement to ozone concentration monitoring with continuous instruments. (C) 2009 Elsevier Ltd. All rights reserved.
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