Ice nucleation properties of volcanic ash from Eyjafjallajökull
The ice nucleation ability of volcanic ash particles collected close to the Icelandic volcano Eyjafjallajökull during its eruptions in April and May 2010 is investigated experimentally, in the immersion and deposition modes, and applied to atmospheric conditions by comparison with airborne measureme...
Published in: | Atmospheric Chemistry and Physics |
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Online Access: | https://doi.org/10.5194/acp-11-9911-2011 https://www.atmos-chem-phys.net/11/9911/2011/ |
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ftcopernicus:oai:publications.copernicus.org:acp11480 2023-05-15T16:09:31+02:00 Ice nucleation properties of volcanic ash from Eyjafjallajökull Hoyle, C. R. Pinti, V. Welti, A. Zobrist, B. Marcolli, C. Luo, B. Höskuldsson, Á. Mattsson, H. B. Stetzer, O. Thorsteinsson, T. Larsen, G. Peter, T. 2018-01-15 info:eu-repo/semantics/application/pdf https://doi.org/10.5194/acp-11-9911-2011 https://www.atmos-chem-phys.net/11/9911/2011/ eng eng info:eu-repo/grantAgreement/EC/FP7/226365 doi:10.5194/acp-11-9911-2011 https://www.atmos-chem-phys.net/11/9911/2011/ info:eu-repo/semantics/openAccess eISSN: 1680-7324 info:eu-repo/semantics/Text 2018 ftcopernicus https://doi.org/10.5194/acp-11-9911-2011 2019-12-24T09:56:38Z The ice nucleation ability of volcanic ash particles collected close to the Icelandic volcano Eyjafjallajökull during its eruptions in April and May 2010 is investigated experimentally, in the immersion and deposition modes, and applied to atmospheric conditions by comparison with airborne measurements and microphysical model calculations. The number of ash particles which are active as ice nuclei (IN) is strongly temperature dependent, with a very small minority being active in the immersion mode at temperatures of 250–263 K. Average ash particles show only a moderate effect on ice nucleation, by inducing freezing at temperatures between 236 K and 240 K (i.e. approximately 3–4 K higher than temperatures required for homogeneous ice nucleation, measured with the same instrument). By scaling the results to aircraft and lidar measurements of the conditions in the ash plume days down wind of the eruption, and by applying a simple microphysical model, it was found that the IN active in the immersion mode in the range 250–263 K generally occurred in atmospheric number densities at the lower end of those required to have an impact on ice cloud formation. However, 3–4 K above the homogeneous freezing point, immersion mode IN number densities a few days down wind of the eruption were sufficiently high to have a moderate influence on ice cloud formation. The efficiency of IN in the deposition mode was found to be poor except at very cold conditions (<238 K), when they reach an efficiency similar to that of mineral dust with the onset of freezing at 10 % supersaturation with respect to ice, and with the frozen fraction nearing its maximum value at a supersaturation 20 %. In summary, these investigations suggest volcanic ash particles to have only moderate effects on atmospheric ice formation. Other/Unknown Material Eyjafjallajökull Copernicus Publications: E-Journals Atmospheric Chemistry and Physics 11 18 9911 9926 |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
The ice nucleation ability of volcanic ash particles collected close to the Icelandic volcano Eyjafjallajökull during its eruptions in April and May 2010 is investigated experimentally, in the immersion and deposition modes, and applied to atmospheric conditions by comparison with airborne measurements and microphysical model calculations. The number of ash particles which are active as ice nuclei (IN) is strongly temperature dependent, with a very small minority being active in the immersion mode at temperatures of 250–263 K. Average ash particles show only a moderate effect on ice nucleation, by inducing freezing at temperatures between 236 K and 240 K (i.e. approximately 3–4 K higher than temperatures required for homogeneous ice nucleation, measured with the same instrument). By scaling the results to aircraft and lidar measurements of the conditions in the ash plume days down wind of the eruption, and by applying a simple microphysical model, it was found that the IN active in the immersion mode in the range 250–263 K generally occurred in atmospheric number densities at the lower end of those required to have an impact on ice cloud formation. However, 3–4 K above the homogeneous freezing point, immersion mode IN number densities a few days down wind of the eruption were sufficiently high to have a moderate influence on ice cloud formation. The efficiency of IN in the deposition mode was found to be poor except at very cold conditions (<238 K), when they reach an efficiency similar to that of mineral dust with the onset of freezing at 10 % supersaturation with respect to ice, and with the frozen fraction nearing its maximum value at a supersaturation 20 %. In summary, these investigations suggest volcanic ash particles to have only moderate effects on atmospheric ice formation. |
format |
Other/Unknown Material |
author |
Hoyle, C. R. Pinti, V. Welti, A. Zobrist, B. Marcolli, C. Luo, B. Höskuldsson, Á. Mattsson, H. B. Stetzer, O. Thorsteinsson, T. Larsen, G. Peter, T. |
spellingShingle |
Hoyle, C. R. Pinti, V. Welti, A. Zobrist, B. Marcolli, C. Luo, B. Höskuldsson, Á. Mattsson, H. B. Stetzer, O. Thorsteinsson, T. Larsen, G. Peter, T. Ice nucleation properties of volcanic ash from Eyjafjallajökull |
author_facet |
Hoyle, C. R. Pinti, V. Welti, A. Zobrist, B. Marcolli, C. Luo, B. Höskuldsson, Á. Mattsson, H. B. Stetzer, O. Thorsteinsson, T. Larsen, G. Peter, T. |
author_sort |
Hoyle, C. R. |
title |
Ice nucleation properties of volcanic ash from Eyjafjallajökull |
title_short |
Ice nucleation properties of volcanic ash from Eyjafjallajökull |
title_full |
Ice nucleation properties of volcanic ash from Eyjafjallajökull |
title_fullStr |
Ice nucleation properties of volcanic ash from Eyjafjallajökull |
title_full_unstemmed |
Ice nucleation properties of volcanic ash from Eyjafjallajökull |
title_sort |
ice nucleation properties of volcanic ash from eyjafjallajökull |
publishDate |
2018 |
url |
https://doi.org/10.5194/acp-11-9911-2011 https://www.atmos-chem-phys.net/11/9911/2011/ |
genre |
Eyjafjallajökull |
genre_facet |
Eyjafjallajökull |
op_source |
eISSN: 1680-7324 |
op_relation |
info:eu-repo/grantAgreement/EC/FP7/226365 doi:10.5194/acp-11-9911-2011 https://www.atmos-chem-phys.net/11/9911/2011/ |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/acp-11-9911-2011 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
11 |
container_issue |
18 |
container_start_page |
9911 |
op_container_end_page |
9926 |
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1766405385735897088 |