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This report presents VOC measurements carried out during 2016 at EMEP monitoring sites. In total, 19 sites reported VOC data from EMEP VOC sites this year. Some of the data sets are considered preliminary and are not included in the report.
The monitoring of NMHC (non-methane hydrocarbons) has become more diverse with time in terms of instrumentation. Starting in the early 1990s with standardized methods based on manual sampling in steel canisters with subsequent analyses at the lab, the methods now consist of a variety of instruments and measurement principles, including automated continuous monitors and manual flask samples. For oxygenated VOCs (OVOCs), sampling in DNPH-tubes with subsequent lab-analyses is still the only method in use at EMEP sites.
Within the EU infrastructure project ACTRIS-2, data quality issues related to measurements of VOC have been an important topic. Many of the institutions providing VOC data to EMEP have participated in the ACTRIS-2 project, either as formal partners or on a voluntary basis. Participation in ACTRIS-2 has meant an extensive effort with data checking including detailed discussions between the ACTRIS community and individual participants. There is no doubt that this extensive effort has benefited the EMEP program and has led to improved data quality in general.
Comparison between median levels in 2016 compared to the medians of the previous 10-years period, revealed a similar north-to-south pattern for several species.
Changes in instrumentation, procedures, station network etc. during the last two decades make it difficult to provide a rigorous and pan-European assessment of long-term trends of the observed VOCs. In this report we have estimated the long-term trends in NMHC over the 2000-2016 period at six selected sites by two independent statistical methods. These estimates indicate marked differences in the trends for the individual species. Small or non-significant trends were found for ethane over this period followed by propane which also showed fairly small reductions. On the other hand, components linked to road traffic (ethene, ethyne and toluene) showed the strongest drop in mean concentrations, up to 60-80% at some stations. The trend in n-butane was between these two groups of species with an estimated drop in the annual mean concentration of 20-40% over the 2000-2016 period
NILU
2018
This report presents VOC measurements carried out during 2017 at EMEP monitoring sites. In total, 20 sites reported VOC data from EMEP VOC sites this year. Some of the data sets are considered preliminary and are not included in the report. The monitoring of NMHC (non-methane hydrocarbons) has become more diverse with time in terms of instrumentation. Starting in the early 1990s with standardized methods based on manual sampling in steel canisters with subsequent analyses at the lab, the methods now consist of a variety of instruments and measurement principles, including automated continuous monitors and manual flask samples. For oxygenated VOCs (OVOCs), sampling in DNPH-tubes with subsequent labanalyses is still the only method in use at EMEP sites. Within the EU infrastructure project ACTRIS-2, data quality issues related to measurements of VOC have been an important topic. Many of the institutions providing VOC data to EMEP have participated in the ACTRIS-2 project, either as formal partners or on a voluntary basis. Participation in ACTRIS-2 has meant an extensive effort with data checking including detailed discussions between the ACTRIS community and individual participants. There is no doubt that this extensive effort has benefited the EMEP program and has led to improved data quality in general. Comparison between median levels in 2017 compared to the medians of the previous 10-years period, revealed a similar north-to-south pattern for several species. Changes in instrumentation, procedures, station network etc. during the last two decades make it difficult to provide a rigorous and pan-European assessment of long-term trends of the observed VOCs. In this report we have estimated the longterm trends in NMHC over the 2000-2017 period at six selected sites by two independent statistical methods. These estimates indicate marked differences in the trends for the individual species. Small or non-significant trends were found for ethane over this period followed by propane which also showed fairly small reductions. On the other hand, components linked to road traffic (ethene, ethyne and toluene) showed the strongest drop in mean concentrations, up to 60-80% at some stations. The trend in n-butane was between these two groups of species with an estimated drop in the annual mean concentration of 20-50% over the 2000-2017 period.
NILU
2019
This report presents VOC (volatile organic compound) measurements carried out during 2018 at EMEP monitoring sites. In total, 20 sites reported VOC-data from EMEP VOC sites this year. Some of the data-sets are considered preliminary and are not included in the report.
The monitoring of NMHC (non-methane hydrocarbons) has become more diverse with time in terms of instrumentation. Starting in the early 1990s with standardized methods based on manual sampling in steel canisters with subsequent analyses at the lab, the methods now consist of a variety of instruments and measurement principles, including automated continuous monitors and manual flask samples. For oxygenated VOCs (OVOCs), sampling in DNPH-tubes with subsequent lab-analyses is still the only method in use at EMEP sites.
Within the EU infrastructure project ACTRIS-2, data quality issues related to measurements of VOC have been an important topic. Many of the institutions providing VOC-data to EMEP have participated in the ACTRIS-2 project, either as formal partners or on a voluntary basis. Participation in ACTRIS-2 has meant an extensive effort with data-checking including detailed discussions between the ACTRIS community and individual participants. There is no doubt that this extensive effort has benefited the EMEP-program and has led to improved data quality in general.
Comparison between median levels in 2018 and the medians of the previous 10-years period, revealed a similar north-to-south pattern for several species.
Changes in instrumentation, procedures, station network etc. during the last two decades make it difficult to provide a rigorous and pan-European assessment of long-term trends of the observed VOCs. In this report, we have estimated the long-term trends in NMHC over the 2000-2018 period at six sites by two independent statistical methods. These estimates indicate marked differences in the trends for the individual species. Small or non-significant trends were found for ethane over this period followed by propane which also showed fairly small reductions. On the other hand, components linked to road traffic (ethene, ethyne and benzene) showed the strongest drop in mean concentrations, up to 60-80% at some stations.
The persistent heatwave in summer 2018 in northern and central Europe lead to higher isoprene-levels than normal. The data indicate a clear relationship between isoprene and afternoon temperature at the sites. An exponential fit is seen to be well suited for the relationship between isoprene and temperature.
NILU
2020
This report presents VOC (volatile organic compound) measurements carried out during 2019 at EMEP monitoring sites. In total, 19 sites reported VOC-data from EMEP VOC sites this year. Some of the data-sets are considered preliminary and are not included in the report.
The monitoring of VOC has become more diverse with time in terms of instrumentation. Starting in the early 1990s with standardized methods based on manual sampling in steel canisters and adsorption tubes with subsequent analyses at the lab, the methods now consist of a variety of instruments and measurement principles, including automated continuous monitors and manual flask samples.
Within the EU infrastructure project ACTRIS, data quality issues related to measurements of VOC are an important topic. Many of the institutions providing VOC-data to EMEP are participating in the ACTRIS infrastructure project, either as formal partners or on a voluntary basis. Participation in ACTRIS means an extensive effort with data-checking including detailed discussions between the ACTRIS community and individual participants. There is no doubt that this extensive effort has benefited the EMEP-program substantially and has led to improved data quality in general.
Comparison between median levels in 2019 and the medians of the previous 10-years period, revealed similar geographical patterns as in the previous years. Changes in instrumentation, procedures and station network with time make it difficult though to provide a rigorous and pan-European assessment of long-term trends of the observed VOCs. In this report, we have estimated the trends in NMHC over the 2000-2019 period at five sites by three independent statistical methods. All three methods gave comparable estimates of the trends, although the Mann-Kendall method based on annual data (compared to daily data for the other two methods) found fewer significant trends.
These estimates indicate marked differences in the long-term trends for the individual species. Small or non-significant trends were found for ethane during 2000-2019. Propane also showed fairly small reductions. On the other hand, components linked to road traffic (ethene, ethyne and benzene) showed the strongest drop in mean concentrations, up to 60-80% at some stations.
NILU
2021
This report documents the EMEP VOC monitoring carried out in 2022. The levels of the measured in 2022 are presented as well as the 2022-status and history of the VOC programme. The geographical pattern of the species in Europe is discussed as well as the long-term trend during the last 20 years.
NILU
2024
VOC measurements by PTR-ToF-MS at the Birkenes Observatory. A summary report. NILU OR
Et høy-oppløselig «proton-transfer-reaction time-of-flight» massespektrometer (PTR-ToF-MS) ble brukt til online, sanntids målinger av flyktige organiske forbindelser (VOC) på Birkenes-observatoriet i Sør-Norge. Målingene ble utført i løpet av våren og sommeren 2012, og i januar og begynnelsen av februar 2013. Her presenterer vi standard dataprodukter fra PTR-MS-målingene, slik som volumblandingsforhold av metanol, acetonitril, acetaldehyd, aceton, dimetylsulfid, isopren, metacrolein + metylvinylketon, metyletylketon, benzen, toluen, C8-alkylbenzener, C9-alkylbenzener og summen av monoterpen-isomerer. Forsøksvise data for maursyre, eddiksyre, pinonaldehyd og tre uidentifiserte signaler (m/z 87.080, m/z 89.060 og m/z 101.098) er også rapportert. PT-ToF-MS- massespektrene ble dominert av oksygenerte VOCer både om sommeren og vinteren. De rene hydrokarbonene besto for det meste av aromatiske hydrokarboner (benzen, toluen, C8-alkylbenzener) om vinteren og biogene hydrokarboner (monoterpener og isopren) om sommeren. Sommerdataene bekrefter at Birkenes-observatoriet er et interessant område i den boreo-nemorale vegetasjonssonen hvor det er mulig å observere både utslipp av monoterpener og isopren og deres fotokjemiske omvandling i atmosfæren.
2014