Observations and modeling of melting-layer microphysical processes in MC3E

 
Poster PDF

Authors

Aaron Bansemer — National Center for Atmospheric Research (NCAR)
Wojciech Grabowski — National Center for Atmospheric Research (NCAR)
Andrew Heymsfield — National Center for Atmospheric Research (NCAR)
Hugh Clifton Morrison — University Corporation for Atmospheric Research

Category

Field Campaigns

Description

Microphysical factors controlling cold pool evolution are uncertain and lead to considerable uncertainty in simulations of aerosol effects on organized deep convection. In particular, microphysical processes in stratiform rain regions of mesoscale convective systems are not well understood, especially within and above the melting layer. In an effort to reduce these uncertainties we have analyzed in situ observations of cloud particle size distributions and particle shape during the Midlatitude Continental Convective Clouds Experiment (MC3E), with particular focus on aircraft spiral ascent/descents through the melting layer during stratiform and convective trailing stratiform events over the ARM Southern Great Plains (SGP) site. Through newly developed particle shape analysis we can detect details of the melting process, showing the evolution of melting from small particle sizes to large ones. In addition, improved estimates of particle fall velocity, number concentration, and mass flux through the melting layer have been developed. These observations are compared with results from quasi-idealized cloud system-resolving model simulations, focusing on the May 20, 2011, squall line case.