Identification

Title

Characterizing the occurrence and spatial heterogeneity of liquid, ice, and mixed phase low-level clouds over the southern ocean using in situ observations acquired during SOCRATES

Abstract

Supercooled liquid water (SLW) and mixed phase clouds containing SLW and ice over the Southern Ocean (SO) are poorly represented in global climate and numerical weather prediction models. Observed SLW exists at lower temperatures than threshold values used to characterize its detrainment from convection in model parameterizations, and processes controlling its formation and removal are poorly understood. High-resolution observations are needed to better characterize SLW over the SO. This study characterizes the frequency and spatial distribution of different cloud phases (liquid, ice, and mixed) using in situ observations acquired during the Southern Ocean Clouds, Radiation, Aerosol Transport Experiment Study. Cloud particle phase is identified using multiple cloud probes. Results show occurrence frequencies of liquid phase samples up to 70% between -20 degrees C and 0 degrees C and of ice phase samples up to 10% between -5 degrees C and 0 degrees C. Cloud phase spatial heterogeneity is determined by relating the total number of 1 s samples from a given cloud to the number of segments whose neighboring samples are the same phase. Mixed phase conditions are the most spatially heterogeneous from -20 degrees C to 0 degrees C, whereas liquid phase conditions from -10 degrees C to 0 degrees C and ice phase conditions from -20 degrees C to -10 degrees C are the least spatially heterogeneous. Greater spatial heterogeneity is associated with broader distributions of vertical velocity. Decreasing droplet concentrations and increasing number-weighted mean liquid diameters occur within mixed phase clouds as the liquid water fraction decreases, possibly suggesting preferential evaporation of smaller drops during the Wegener-Bergeron-Findeisen process.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.org/ark:/85065/d7sj1q19

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2021-06-16T00:00:00Z

Frequency of update

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact