Physico-Chemical Behaviour of Atmospheric Pollutants, 1990
... When compared to its half-life with respect to the reaction with DMS, which varied from 1 to ... more ... When compared to its half-life with respect to the reaction with DMS, which varied from 1 to 7 min, this factor can usually be neglected. ... o ; SO2=x 4 ...-+ 4. -t ~0 a..,.W..o~O.,..o__ , - u .'~ '~e --- ~0" - o /J '~'A.,,.A....AI ' '" ' ' I .... I .... I /"*" o 50 lOO 15o i , , , ii 300 400 sou sou 700 sou ...
DESCRIPTION This report constitutes work carried out at the Centre for Research Into Ecological a... more DESCRIPTION This report constitutes work carried out at the Centre for Research Into Ecological and Environmental Modelling (CREEM) at the University of St. Andrews, performed under contract for Marine Scotland; SB9 (CR/2012/05)
Terpenes react quite rapidly with ambient ozone and lead via ozonides to highly oxidizing radical... more Terpenes react quite rapidly with ambient ozone and lead via ozonides to highly oxidizing radicals and consecutive products forming aerosols. In the presence of SO2 sulphur containing compounds, mainly as sulphate, are formed. By means of gas chromatography/mass spectrometry and by comparison with known spectra the main products of the reaction of ß‐pinene (as a model compound) with ozone and
This review is based on the results obtained from the Danish AMAP programme for the Arctic atmosp... more This review is based on the results obtained from the Danish AMAP programme for the Arctic atmosphere during the 1990s. The purpose of the programme is to quantify the pollution, apportion source contributions, follow the trends, and identify midlatitude source areas and transport pathways. The project has been carried out in North Greenland as integrated monitoring, which is an interacting combination of field measurements and model calculations of atmospheric transport and transformation in the Northern Hemisphere. At the monitoring site at Station Nord the large and seasonally recurrent variations in the pollutant concentrations are testimony to the influence in this region of the phenomenon of Arctic Haze. These results can only be understood in terms of long range transport from distant pollution sources. The measurements also comprise a large number of particle-born elements. These results are used to build receptor models, which show that the ambient concentrations and their variations to a high degree can be explained by the influence of only four source types of both natural and anthropogenic nature. The challenging phenomena of atmospheric ozone and mercury depletion around Polar sunrise have been studied at Station Nord over several years. The results show that these two phenomena are closely connected, presumably through photochemical reactions with atmospheric halogens released from sea ice. A large-scale Eulerian model system for the Northern Hemisphere has been developed in this AMAP project. The validity of the model is illustrated by comparisons between measured and calculated air concentrations. The model has been used to calculate both the vertical distribution and the atmospheric depositions for several pollutants at various locations in Greenland and split into quantified contributions from different and geographically distant source areas. Mercury deposition estimates for the Northern Hemisphere are also presented. They show that the mercury depletion events are accompanied by very intense depositions to land and sea of reactive mercury that may seriously affect the Arctic ecosystems. Finally, measurement and model data are combined to demonstrate, despite considerable meteorological noise, that ambient air concentrations in North-eastern Greenland have decreased during the last decade. Quantified trends, attributable to emission reductions in distant source areas, are presented for several pollutants.
Physico-Chemical Behaviour of Atmospheric Pollutants, 1990
... When compared to its half-life with respect to the reaction with DMS, which varied from 1 to ... more ... When compared to its half-life with respect to the reaction with DMS, which varied from 1 to 7 min, this factor can usually be neglected. ... o ; SO2=x 4 ...-+ 4. -t ~0 a..,.W..o~O.,..o__ , - u .'~ '~e --- ~0" - o /J '~'A.,,.A....AI ' '" ' ' I .... I .... I /"*" o 50 lOO 15o i , , , ii 300 400 sou sou 700 sou ...
DESCRIPTION This report constitutes work carried out at the Centre for Research Into Ecological a... more DESCRIPTION This report constitutes work carried out at the Centre for Research Into Ecological and Environmental Modelling (CREEM) at the University of St. Andrews, performed under contract for Marine Scotland; SB9 (CR/2012/05)
Terpenes react quite rapidly with ambient ozone and lead via ozonides to highly oxidizing radical... more Terpenes react quite rapidly with ambient ozone and lead via ozonides to highly oxidizing radicals and consecutive products forming aerosols. In the presence of SO2 sulphur containing compounds, mainly as sulphate, are formed. By means of gas chromatography/mass spectrometry and by comparison with known spectra the main products of the reaction of ß‐pinene (as a model compound) with ozone and
This review is based on the results obtained from the Danish AMAP programme for the Arctic atmosp... more This review is based on the results obtained from the Danish AMAP programme for the Arctic atmosphere during the 1990s. The purpose of the programme is to quantify the pollution, apportion source contributions, follow the trends, and identify midlatitude source areas and transport pathways. The project has been carried out in North Greenland as integrated monitoring, which is an interacting combination of field measurements and model calculations of atmospheric transport and transformation in the Northern Hemisphere. At the monitoring site at Station Nord the large and seasonally recurrent variations in the pollutant concentrations are testimony to the influence in this region of the phenomenon of Arctic Haze. These results can only be understood in terms of long range transport from distant pollution sources. The measurements also comprise a large number of particle-born elements. These results are used to build receptor models, which show that the ambient concentrations and their variations to a high degree can be explained by the influence of only four source types of both natural and anthropogenic nature. The challenging phenomena of atmospheric ozone and mercury depletion around Polar sunrise have been studied at Station Nord over several years. The results show that these two phenomena are closely connected, presumably through photochemical reactions with atmospheric halogens released from sea ice. A large-scale Eulerian model system for the Northern Hemisphere has been developed in this AMAP project. The validity of the model is illustrated by comparisons between measured and calculated air concentrations. The model has been used to calculate both the vertical distribution and the atmospheric depositions for several pollutants at various locations in Greenland and split into quantified contributions from different and geographically distant source areas. Mercury deposition estimates for the Northern Hemisphere are also presented. They show that the mercury depletion events are accompanied by very intense depositions to land and sea of reactive mercury that may seriously affect the Arctic ecosystems. Finally, measurement and model data are combined to demonstrate, despite considerable meteorological noise, that ambient air concentrations in North-eastern Greenland have decreased during the last decade. Quantified trends, attributable to emission reductions in distant source areas, are presented for several pollutants.
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