Efficiency of the deposition mode ice nucleation on mineral dust particles
The deposition mode ice nucleation efficiency of various dust aerosols was investigated at cirrus cloud temperatures between 196 and 223 K using the aerosol and cloud chamber facility AIDA (Aerosol Interaction and Dynamics in the Atmosphere). Arizona test dust (ATD) as a reference material and two d...
Main Authors: | , , , , , , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Copernicus Publications
2006-01-01
|
Series: | Atmospheric Chemistry and Physics |
Online Access: | http://www.atmos-chem-phys.net/6/3007/2006/acp-6-3007-2006.pdf |
_version_ | 1818669447917862912 |
---|---|
author | O. Möhler P. R. Field P. R. Field P. Connolly S. Benz H. Saathoff M. Schnaiter R. Wagner R. Cotton M. Krämer A. Mangold A. Mangold A. J. Heymsfield |
author_facet | O. Möhler P. R. Field P. R. Field P. Connolly S. Benz H. Saathoff M. Schnaiter R. Wagner R. Cotton M. Krämer A. Mangold A. Mangold A. J. Heymsfield |
author_sort | O. Möhler |
collection | DOAJ |
description | The deposition mode ice nucleation efficiency of various dust aerosols was investigated at cirrus cloud temperatures between 196 and 223 K using the aerosol and cloud chamber facility AIDA (Aerosol Interaction and Dynamics in the Atmosphere). Arizona test dust (ATD) as a reference material and two dust samples from the Takla Makan desert in Asia (AD1) and the Sahara (SD2) were used for the experiments at simulated cloud conditions. The dust particle sizes were almost lognormally distributed with mode diameters between 0.3 and 0.5 μm and geometric standard deviations between 1.6 and 1.9. Deposition ice nucleation was most efficient on ATD particles with ice-active particle fractions of about 0.6 and 0.8 at an ice saturation ratio <i>S<sub>i</sub></i><1.15 and temperatures of 223 and 209 K, respectively. No significant change of the ice nucleation efficiency was found in up to three subsequent cycles of ice activation and evaporation with the same ATD aerosol. This indicates that the phenomenon of preactivation does not apply to ATD particles. The desert dust samples SD2 and AD1 showed a significantly lower fraction of active deposition nuclei, about 0.25 at 223 K and <i>S<sub>i</sub></i><1.35. For all samples the ice activated aerosol fraction could be approximated by an exponential equation as function of <i>S<sub>i</sub></i>. This indicates that deposition ice nucleation on mineral particles may not be treated in the same stochastic sense as homogeneous freezing. The suggested formulation of ice activation spectra may be used to calculate the formation rate of ice crystals in models, if the number concentration of dust particles is known. More experimental work is needed to quantify the variability of the ice activation spectra as function of the temperature and dust particle properties. |
first_indexed | 2024-12-17T06:52:22Z |
format | Article |
id | doaj.art-1dea9ecc82cb4a7cb5fd8d24ad879c33 |
institution | Directory Open Access Journal |
issn | 1680-7316 1680-7324 |
language | English |
last_indexed | 2024-12-17T06:52:22Z |
publishDate | 2006-01-01 |
publisher | Copernicus Publications |
record_format | Article |
series | Atmospheric Chemistry and Physics |
spelling | doaj.art-1dea9ecc82cb4a7cb5fd8d24ad879c332022-12-21T21:59:34ZengCopernicus PublicationsAtmospheric Chemistry and Physics1680-73161680-73242006-01-0161030073021Efficiency of the deposition mode ice nucleation on mineral dust particlesO. MöhlerP. R. FieldP. R. FieldP. ConnollyS. BenzH. SaathoffM. SchnaiterR. WagnerR. CottonM. KrämerA. MangoldA. MangoldA. J. HeymsfieldThe deposition mode ice nucleation efficiency of various dust aerosols was investigated at cirrus cloud temperatures between 196 and 223 K using the aerosol and cloud chamber facility AIDA (Aerosol Interaction and Dynamics in the Atmosphere). Arizona test dust (ATD) as a reference material and two dust samples from the Takla Makan desert in Asia (AD1) and the Sahara (SD2) were used for the experiments at simulated cloud conditions. The dust particle sizes were almost lognormally distributed with mode diameters between 0.3 and 0.5 μm and geometric standard deviations between 1.6 and 1.9. Deposition ice nucleation was most efficient on ATD particles with ice-active particle fractions of about 0.6 and 0.8 at an ice saturation ratio <i>S<sub>i</sub></i><1.15 and temperatures of 223 and 209 K, respectively. No significant change of the ice nucleation efficiency was found in up to three subsequent cycles of ice activation and evaporation with the same ATD aerosol. This indicates that the phenomenon of preactivation does not apply to ATD particles. The desert dust samples SD2 and AD1 showed a significantly lower fraction of active deposition nuclei, about 0.25 at 223 K and <i>S<sub>i</sub></i><1.35. For all samples the ice activated aerosol fraction could be approximated by an exponential equation as function of <i>S<sub>i</sub></i>. This indicates that deposition ice nucleation on mineral particles may not be treated in the same stochastic sense as homogeneous freezing. The suggested formulation of ice activation spectra may be used to calculate the formation rate of ice crystals in models, if the number concentration of dust particles is known. More experimental work is needed to quantify the variability of the ice activation spectra as function of the temperature and dust particle properties.http://www.atmos-chem-phys.net/6/3007/2006/acp-6-3007-2006.pdf |
spellingShingle | O. Möhler P. R. Field P. R. Field P. Connolly S. Benz H. Saathoff M. Schnaiter R. Wagner R. Cotton M. Krämer A. Mangold A. Mangold A. J. Heymsfield Efficiency of the deposition mode ice nucleation on mineral dust particles Atmospheric Chemistry and Physics |
title | Efficiency of the deposition mode ice nucleation on mineral dust particles |
title_full | Efficiency of the deposition mode ice nucleation on mineral dust particles |
title_fullStr | Efficiency of the deposition mode ice nucleation on mineral dust particles |
title_full_unstemmed | Efficiency of the deposition mode ice nucleation on mineral dust particles |
title_short | Efficiency of the deposition mode ice nucleation on mineral dust particles |
title_sort | efficiency of the deposition mode ice nucleation on mineral dust particles |
url | http://www.atmos-chem-phys.net/6/3007/2006/acp-6-3007-2006.pdf |
work_keys_str_mv | AT omohler efficiencyofthedepositionmodeicenucleationonmineraldustparticles AT prfield efficiencyofthedepositionmodeicenucleationonmineraldustparticles AT prfield efficiencyofthedepositionmodeicenucleationonmineraldustparticles AT pconnolly efficiencyofthedepositionmodeicenucleationonmineraldustparticles AT sbenz efficiencyofthedepositionmodeicenucleationonmineraldustparticles AT hsaathoff efficiencyofthedepositionmodeicenucleationonmineraldustparticles AT mschnaiter efficiencyofthedepositionmodeicenucleationonmineraldustparticles AT rwagner efficiencyofthedepositionmodeicenucleationonmineraldustparticles AT rcotton efficiencyofthedepositionmodeicenucleationonmineraldustparticles AT mkramer efficiencyofthedepositionmodeicenucleationonmineraldustparticles AT amangold efficiencyofthedepositionmodeicenucleationonmineraldustparticles AT amangold efficiencyofthedepositionmodeicenucleationonmineraldustparticles AT ajheymsfield efficiencyofthedepositionmodeicenucleationonmineraldustparticles |