Evaluation of an entraining droplet activation parameterization using in situ cloud data
MetadataShow full item record
This study investigates the ability of a droplet activation parameterization (which considers the effects of entrainment and mixing) to reproduce observed cloud droplet number concentration (CDNC) in ambient clouds. Predictions of the parameterization are compared against cloud averages of CDNC from ambient cumulus and stratocumulus clouds sampled during CRYSTAL‐FACE (Key West, Florida, July 2002) and CSTRIPE (Monterey, California, July 2003), respectively. The entrainment parameters required by the parameterization are derived from the observed liquid water content profiles. For the cumulus clouds considered in the study, CDNC is overpredicted by 45% with the adiabatic parameterization. When entrainment is accounted for, the predicted CDNC agrees within 3.5%. Cloud‐averaged CDNC for stratocumulus clouds is well captured when entrainment is not considered. In all cases considered, the entraining parameterization compared favorably against a statistical correlation developed from observations to treat entrainment effects on droplet number. These results suggest that including entrainment effects in the calculation of CDNC, as presented here, could address important overprediction biases associated with using adiabatic CDNC to represent cloud‐scale average values.
The article of record as published may be located at http://dx.doi.org/10.1029/2010JD015324
RightsThis publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.
Showing items related by title, author, creator and subject.
Lu, Miao-Ling; Feingold, Graham; Jonsson, Haflidi; Chuang, Patrick Y.; Gates, Harmony; Flagan, Richard C.; Seinfeld, John H. (2008);Aerosol-cloud relationships are derived from 14 warm continental cumuli cases sampled during the 2006 Gulf of Mexico Atmospheric Composition and Climate Study (GoMACCS) by the Center for Interdisciplinary Remotely-Piloted ...
Whisenhant, Michelle K. (Monterey, California. Naval Postgraduate School, 1999-12);This study utilizes aircraft measurements obtained off the California coast to analyze the geometric, thermodynamic, and micro physical characteristics of convective updrafts and down drafts in the stratocumulus- topped ...
Gerber, H.; Frick, G.; Malinowski, Szymon P.; Jonsson, H.; Khelif, D.; Krueger, Steven K. (2013);An aircraft field study (POST; Physics of Stratocumulus Top) was conducted off the central California coast in July and August 2008 to deal with the known difficulty of measuring entrainment rates in the radiatively ...