Subarctic atmospheric aerosol composition: 3. Measured and modeled properties of cloud condensation nuclei
Aerosol particles can modify cloud properties by acting as cloud condensation nuclei (CCN). Predicting CCN properties is still a challenge and not properly incorporated in current climate models. Atmospheric particle number size distributions, hygroscopic growth factors, and polydisperse CCN number...
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ftempa:oai:dora:empa_25765 2023-05-15T15:11:34+02:00 Subarctic atmospheric aerosol composition: 3. Measured and modeled properties of cloud condensation nuclei Kammermann, Lukas Gysel, Martin Weingartner, Ernest Herich, Hanna Cziczo, Daniel J. Holst, Thomas Svenningsson, Birgitta Arneth, Almut Baltensperger, Urs 2010 https://doi.org/10.1029/2009JD012447 eng eng Wiley Journal of Geophysical Research D: Atmospheres--J. Geophys. Res. D--journals:1630--2169-897X--2169-8996 empa:25765 doi:10.1029/2009JD012447 scopus: 2-s2.0-77649145861 journal id: journals:1630 issn: 2169-897X e-issn: 2169-8996 ut: 000274789500002 Journal Article Text 2010 ftempa https://doi.org/10.1029/2009JD012447 2023-03-13T00:45:42Z Aerosol particles can modify cloud properties by acting as cloud condensation nuclei (CCN). Predicting CCN properties is still a challenge and not properly incorporated in current climate models. Atmospheric particle number size distributions, hygroscopic growth factors, and polydisperse CCN number concentrations were measured at the remote subarctic Stordalen mire, 200 km north of the Arctic Circle in northern Sweden. The CCN number concentration was highly variable, largely driven by variations in the total number of sufficiently large particles, though the variability of chemical composition was increasingly important for decreasing supersaturation. The hygroscopicity of particles measured by a hygroscopicity tandem differential mobility analyzer (HTDMA) was in agreement with large critical diameters observed for CCN activation ( κ ≈ 0.07-0.21 for D = 50-200 nm). Size distribution and time- and size-resolved HTDMA data were used to predict CCN number concentrations. Agreement of predictions with measured CCN within ± 11% was achieved using parameterized Khler theory and assuming a surface tension of pure water. The sensitivity of CCN predictions to various simplifying assumptions was further explored: We found that (1) ignoring particle mixing state did not affect CCN predictions, (2) averaging the HTDMA data in time with retaining the size dependence did not introduce a substantial bias, while individual predictions became more uncertain, and (3) predictions involving the hygroscopicity parameter recommended in literature for continental sites ( κ ≈ 0.3 0.1) resulted in a significant prediction bias. Future modeling studies should therefore at least aim at using averaged, size-resolved, site-specific hygroscopicity or chemical composition data for predictions of CCN number concentrations. Article in Journal/Newspaper Arctic Northern Sweden Subarctic DORA Empa Arctic Stordalen ENVELOPE(7.337,7.337,62.510,62.510) Journal of Geophysical Research 115 D4 |
institution |
Open Polar |
collection |
DORA Empa |
op_collection_id |
ftempa |
language |
English |
description |
Aerosol particles can modify cloud properties by acting as cloud condensation nuclei (CCN). Predicting CCN properties is still a challenge and not properly incorporated in current climate models. Atmospheric particle number size distributions, hygroscopic growth factors, and polydisperse CCN number concentrations were measured at the remote subarctic Stordalen mire, 200 km north of the Arctic Circle in northern Sweden. The CCN number concentration was highly variable, largely driven by variations in the total number of sufficiently large particles, though the variability of chemical composition was increasingly important for decreasing supersaturation. The hygroscopicity of particles measured by a hygroscopicity tandem differential mobility analyzer (HTDMA) was in agreement with large critical diameters observed for CCN activation ( κ ≈ 0.07-0.21 for D = 50-200 nm). Size distribution and time- and size-resolved HTDMA data were used to predict CCN number concentrations. Agreement of predictions with measured CCN within ± 11% was achieved using parameterized Khler theory and assuming a surface tension of pure water. The sensitivity of CCN predictions to various simplifying assumptions was further explored: We found that (1) ignoring particle mixing state did not affect CCN predictions, (2) averaging the HTDMA data in time with retaining the size dependence did not introduce a substantial bias, while individual predictions became more uncertain, and (3) predictions involving the hygroscopicity parameter recommended in literature for continental sites ( κ ≈ 0.3 0.1) resulted in a significant prediction bias. Future modeling studies should therefore at least aim at using averaged, size-resolved, site-specific hygroscopicity or chemical composition data for predictions of CCN number concentrations. |
format |
Article in Journal/Newspaper |
author |
Kammermann, Lukas Gysel, Martin Weingartner, Ernest Herich, Hanna Cziczo, Daniel J. Holst, Thomas Svenningsson, Birgitta Arneth, Almut Baltensperger, Urs |
spellingShingle |
Kammermann, Lukas Gysel, Martin Weingartner, Ernest Herich, Hanna Cziczo, Daniel J. Holst, Thomas Svenningsson, Birgitta Arneth, Almut Baltensperger, Urs Subarctic atmospheric aerosol composition: 3. Measured and modeled properties of cloud condensation nuclei |
author_facet |
Kammermann, Lukas Gysel, Martin Weingartner, Ernest Herich, Hanna Cziczo, Daniel J. Holst, Thomas Svenningsson, Birgitta Arneth, Almut Baltensperger, Urs |
author_sort |
Kammermann, Lukas |
title |
Subarctic atmospheric aerosol composition: 3. Measured and modeled properties of cloud condensation nuclei |
title_short |
Subarctic atmospheric aerosol composition: 3. Measured and modeled properties of cloud condensation nuclei |
title_full |
Subarctic atmospheric aerosol composition: 3. Measured and modeled properties of cloud condensation nuclei |
title_fullStr |
Subarctic atmospheric aerosol composition: 3. Measured and modeled properties of cloud condensation nuclei |
title_full_unstemmed |
Subarctic atmospheric aerosol composition: 3. Measured and modeled properties of cloud condensation nuclei |
title_sort |
subarctic atmospheric aerosol composition: 3. measured and modeled properties of cloud condensation nuclei |
publisher |
Wiley |
publishDate |
2010 |
url |
https://doi.org/10.1029/2009JD012447 |
long_lat |
ENVELOPE(7.337,7.337,62.510,62.510) |
geographic |
Arctic Stordalen |
geographic_facet |
Arctic Stordalen |
genre |
Arctic Northern Sweden Subarctic |
genre_facet |
Arctic Northern Sweden Subarctic |
op_relation |
Journal of Geophysical Research D: Atmospheres--J. Geophys. Res. D--journals:1630--2169-897X--2169-8996 empa:25765 doi:10.1029/2009JD012447 scopus: 2-s2.0-77649145861 journal id: journals:1630 issn: 2169-897X e-issn: 2169-8996 ut: 000274789500002 |
op_doi |
https://doi.org/10.1029/2009JD012447 |
container_title |
Journal of Geophysical Research |
container_volume |
115 |
container_issue |
D4 |
_version_ |
1766342411773018112 |