 |
| Titel |
Microphysical process rates and global aerosol–cloud interactions |
| VerfasserIn |
A. Gettelman, H. Morrison, C. R. Terai, R. Wood |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 13, no. 19 ; Nr. 13, no. 19 (2013-10-07), S.9855-9867 |
| Datensatznummer |
250085735
|
| Publikation (Nr.) |
 copernicus.org/acp-13-9855-2013.pdf |
|
|
|
|
|
| Zusammenfassung |
| Cloud microphysical process rates control the amount of condensed water in
clouds and impact the susceptibility of precipitation to cloud-drop number
and aerosols. The relative importance of different microphysical processes in
a climate model is analyzed, and the autoconversion and accretion processes
are found to be critical to the condensate budget in most regions. A simple
steady-state model of warm rain formation is used to illustrate that the
diagnostic rain formulations typical of climate models may result in
excessive contributions from autoconversion, compared to observations and
large eddy simulation models with explicit bin-resolved microphysics and rain
formation processes. The behavior does not appear to be caused by the bulk
process rate formulations themselves, because the steady-state model with the
same bulk accretion and autoconversion has reduced contributions from
autoconversion. Sensitivity tests are conducted to analyze how perturbations
to the precipitation microphysics for stratiform clouds impact process rates,
precipitation susceptibility and aerosol–cloud interactions (ACI). With
similar liquid water path, corrections for the diagnostic rain assumptions in
the GCM based on the steady-state model to boost accretion indicate that the
radiative effects of ACI may decrease by 20% in the GCM. Links between
process rates, susceptibility and ACI are not always clear in the GCM. Better
representation of the precipitation process, for example by prognosticating
precipitation mass and number, may help better constrain these effects in
global models with bulk microphysics schemes. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|