Change search
ReferencesLink to record
Permanent link

Direct link
Meteorological and aerosol effects on marine cloud microphysical properties
Show others and affiliations
Number of Authors: 23
2016 (English)In: Journal of Geophysical Research - Atmospheres, ISSN 2169-897X, E-ISSN 2169-8996, Vol. 121, no 8, 4142-4161 p.Article in journal (Refereed) Published
Abstract [en]

Meteorology and microphysics affect cloud formation, cloud droplet distributions, and shortwave reflectance. The Eastern Pacific Emitted Aerosol Cloud Experiment and the Stratocumulus Observations of Los-Angeles Emissions Derived Aerosol-Droplets studies provided measurements in six case studies of cloud thermodynamic properties, initial particle number distribution and composition, and cloud drop distribution. In this study, we use simulations from a chemical and microphysical aerosol-cloud parcel (ACP) model with explicit kinetic drop activation to reproduce observed cloud droplet distributions of the case studies. Four cases had subadiabatic lapse rates, resulting in fewer activated droplets, lower liquid water content, and higher cloud base height than an adiabatic lapse rate. A weighted ensemble of simulations that reflect measured variation in updraft velocity and cloud base height was used to reproduce observed droplet distributions. Simulations show that organic hygroscopicity in internally mixed cases causes small effects on cloud reflectivity (CR) (<0.01), except for cargo ship and smoke plumes, which increased CR by 0.02 and 0.07, respectively, owing to their high organic mass fraction. Organic hygroscopicity had larger effects on droplet concentrations for cases with higher aerosol concentrations near the critical diameter (namely, polluted cases with a modal peak near 0.1 mu m). Differences in simulated droplet spectral widths (k) caused larger differences in CR than organic hygroscopicity in cases with organic mass fractions of 60% or less for the cases shown. Finally, simulations from a numerical parameterization of cloud droplet activation suitable for general circulation models compared well with the ACP model, except under high organic mass fraction.

Place, publisher, year, edition, pages
2016. Vol. 121, no 8, 4142-4161 p.
National Category
Earth and Related Environmental Sciences
Identifiers
URN: urn:nbn:se:su:diva-132521DOI: 10.1002/2015JD024595ISI: 000378318100025OAI: oai:DiVA.org:su-132521DiVA: diva2:952749
Available from: 2016-08-15 Created: 2016-08-15 Last updated: 2016-08-15Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Noone, Kevin J.
By organisation
Department of Environmental Science and Analytical Chemistry
In the same journal
Journal of Geophysical Research - Atmospheres
Earth and Related Environmental Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 1 hits
ReferencesLink to record
Permanent link

Direct link