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  • An Evaluation of Phase, Aerosol-Cloud Interactions and Microphysical Properties of Single- and Multi-Layer Clouds Over the Southern Ocean Using in Situ Observations From SOCRATES
Title: An Evaluation of Phase, Aerosol-Cloud Interactions and Microphysical Properties of Single- and Multi-Layer Clouds Over the Southern Ocean Using in Situ Observations From SOCRATES
Single- and multi-layer clouds are commonly observed over the Southern Ocean in varying synoptic settings, yet few studies have characterized and contrasted their properties. This study provides a statistical analysis of the microphysical properties of single- and multi-layer clouds using in-situ observations acquired during the Southern Ocean Cloud-Radiation Aerosol Transport Experimental Study. The relative frequencies of ice-containing samples (i.e., mixed and ice phase) for multi-layer clouds are 0.05–0.25 greater than for single-layer clouds, depending on cloud layer height. In multi-layer clouds, the lowest cloud layers have the highest ice-containing sample frequencies, which decrease with increasing cloud layer height up to the third highest cloud layer. This suggests a prominent seeder-feeder mechanism over the region. Ice nucleating particle (cloud condensation nuclei) concentrations are positively (negatively) correlated with ice-containing sample frequencies in select cases. Differences in microphysical properties are observed for single- and multi-layer clouds. Drop concentrations (size distributions) are greater (narrower) for single-layer clouds compared with the lowest multi-layer clouds. When differentiating cloud layers by top (single- and highest multi-layer clouds) and non-top layers (underlying multi-layer clouds), total particle size distributions (including liquid and ice) are similarly broader for non-top cloud layers. Additionally, drop concentrations in coupled environments are approximately double those in decoupled environments.  more » « less
Award ID(s):
1744965
PAR ID:
10542147
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley Publishing - AGU journals
Date Published:
Journal Name:
Journal of Geophysical Research: Atmospheres
Volume:
128
Issue:
15
ISSN:
2169-8996
Page Range / eLocation ID:
e2023JD038610
Subject(s) / Keyword(s):
Southern Ocean cloud microphysics aerosol-cloud interactions
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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