Microphysical Properties of Generating Cells over the Southern Ocean: Results from SOCRATES

The Southern Ocean Clouds Radiation Transport Aerosol Transport Experimental Study (SOCRATES) was conducted between 3 January to 26 February 2018 over the Southern Ocean (SO, south of Hobart, Tasmania, in the region between 134°E to 163 °E, and -43°S to -62°S). The temperature, presence and amount of supercooled liquid water, and the size, shape and phase distributions of cloud and precipitation-sized particles were measured by probes installed on the National Science Foundation (NSF)/National Center for Atmospheric Research (NCAR) Gulfstream V (GV) aircraft including a Cloud Droplet Probe, a Fast Two-Dimensional Cloud probe, a Two-Dimensional Stereo probe, and a Rosemount Icing Detector. Measurements of equivalent radar reflectivity factor and the vertical component of radial velocity from the High-Performance Instrumented Airborne Platform for Environmental Research (HIAPER) aircraft Cloud Radar (HCR) provide the context for the in-situ measurements through identification of cloud-top generating cell (GC) cores. Cases were selected when the plane was flying near cloud top, with radar pointed down to identify the GC cores but also the microphysical measurements were available at the same time. Using these collocated observations, various microphysical properties of the nearly ubiquitous GCs are contrasted with those in adjacent clouds outside the GCs. Furthermore, the characteristics of the GCs measured during SOCRATES are contrasted with those measured in mid-latitude winter storms during the Profiling of Winter Storms (PLOWS) project. Thus, several cases on 29 Jan, 4 Feb, and 20 Feb 2018 and the statistical analyses of cloud particle size, shape and phase distributions will be shown to illustrate the unique properties and possible processes of GCs in the SO compared to the continental clouds. This characterization of the properties of the GCs over the Southern Oceans will expand knowledge of the physical processes, and mechanisms acting in GCs over a wider range of conditions than available before.