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Title: Cumulus Cloud and Drizzle Microphysics Relationships With Complete CCN Spectra
Abstract Comparisons of high‐resolution extended range CCN spectra measured at 100 m altitude with cloud and drizzle microphysics in the Rain in Cumulus over the Ocean (RICO) aircraft field project are presented. CCN concentrations,NCCN, active at supersaturations,S, >0.1% showed positive relationships with cloud droplet concentrations,Nc, measured at intermediate (606–976 m) and very high altitudes (1,763–3,699 m). These correlation coefficients,R, progressively increased withSwhile the two‐tailed probabilities, P2, progressively decreased with S to < 10−6at 1.6%S. More important were the positive relationships betweenNCCNactive atS < 0.1% and drizzle drop concentrations,Nd, at high (977–1,662 m), very high and high‐very high altitudes combined (977–3,699 m). All of these relationships were consistent for eight different cloud liquid water content,Lc, thresholds (forNc) andLcbins (forNd) ranging from 0.0002 to 0.3 g/m3. Negative relationships between CCN modality and low altitude (76–475 m) cloudiness coupled with no relationship ofNCCNactive at any S withNcof these low clouds indicated a cloud effect on ambient aerosol. This is a demonstration of clouds causing bimodal aerosol.  more » « less
Award ID(s):
1940645
PAR ID:
10446473
Author(s) / Creator(s):
 ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Journal of Geophysical Research: Atmospheres
Volume:
126
Issue:
15
ISSN:
2169-897X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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