 |
| Titel |
A technique for quantifying heterogeneous ice nucleation in microlitre supercooled water droplets |
| VerfasserIn |
T. F. Whale, B. J. Murray, D. O'Sullivan, T. W. Wilson, N. S. Umo, K. J. Baustian, J. D. Atkinson, D. A. Workneh, G. J. Morris |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1867-1381
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Measurement Techniques ; 8, no. 6 ; Nr. 8, no. 6 (2015-06-15), S.2437-2447 |
| Datensatznummer |
250116431
|
| Publikation (Nr.) |
 copernicus.org/amt-8-2437-2015.pdf |
|
|
|
|
|
| Zusammenfassung |
| In many clouds, the formation of ice requires the presence of particles
capable of nucleating ice. Ice-nucleating particles (INPs) are rare in
comparison to cloud condensation nuclei. However, the fact that only a small
fraction of aerosol particles can nucleate ice means that detection and
quantification of INPs is challenging. This is particularly true at
temperatures above about −20 °C since the population of particles
capable of serving as INPs decreases dramatically with increasing
temperature. In this paper, we describe an experimental technique in which
droplets of microlitre volume containing ice-nucleating material are cooled
down at a controlled rate and their freezing temperatures recorded. The
advantage of using large droplet volumes is that the surface area per
droplet is vastly larger than in experiments focused on single aerosol
particles or cloud-sized droplets. This increases the probability of
observing the effect of less common, but important, high-temperature INPs
and therefore allows the quantification of their ice nucleation efficiency.
The potential artefacts which could influence data from this experiment, and
other similar experiments, are mitigated and discussed. Experimentally
determined heterogeneous ice nucleation efficiencies for K-feldspar
(microcline), kaolinite, chlorite, NX-illite, Snomax® and
silver iodide are presented. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|