 |
| Titel |
Supersaturation calculation in large eddy simulation models for prediction of the droplet number concentration |
| VerfasserIn |
O. Thouron, J.-L. Brenguier, F. Burnet |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1991-959X
|
| Digitales Dokument |
URL |
| Erschienen |
In: Geoscientific Model Development ; 5, no. 3 ; Nr. 5, no. 3 (2012-05-23), S.761-772 |
| Datensatznummer |
250002615
|
| Publikation (Nr.) |
 copernicus.org/gmd-5-761-2012.pdf |
|
|
|
|
|
| Zusammenfassung |
| A new parameterization scheme is described for calculation of
supersaturation in LES models that specifically aims at the simulation of
cloud condensation nuclei (CCN) activation and prediction of the droplet
number concentration. The scheme is tested against current parameterizations
in the framework of the Meso-NH LES model. It is shown that the saturation
adjustment scheme, based on parameterizations of CCN activation in a
convective updraft, overestimates the droplet concentration in the cloud
core, while it cannot simulate cloud top supersaturation production due to
mixing between cloudy and clear air. A supersaturation diagnostic scheme
mitigates these artefacts by accounting for the presence of already
condensed water in the cloud core, but it is too sensitive to supersaturation
fluctuations at cloud top and produces spurious CCN activation during cloud
top mixing. The proposed pseudo-prognostic scheme shows performance similar
to the diagnostic one in the cloud core but significantly mitigates CCN
activation at cloud top. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|