AS1.27Observing and modeling processes in moderately supercooled clouds
|Convener: Vaughan Phillips | Co-Conveners: Constantin Andronache , Franz Conen , Trude Storelvmo|
While ice-only clouds consist entirely of ice crystals, and water clouds are composed entirely of liquid water drops, an important class of mixed-phase clouds is wide spread in the atmosphere. Mixed-phase clouds contain both liquid and ice water in the same cloudy volume that interact via microphysical processes. They present a variety of distinct phenomena, as well as observational and modeling challenges. Particularly, the atmospheric radiation balance and hydrological cycle are sensitive to the partitioning of cloud phase. In moderately supercooled clouds biological particles are likely responsible for much of the phase change from liquid to ice.
We invite presentations on mixed-phase clouds – specifically clouds containing both water drops and ice crystals - with focus on the following topics:
a) ground based, aircraft and satellite observations of mixed clouds using a range of instruments (radar, lidar, MWR, radiosonde, Doppler radar spectra); characterization of cloud microphysics, retrieval algorithms, validations, intercomparisons, datasets;
b) modeling of mixed phase clouds in regional and global models;
c) precipitation dependence on abundance of biological particles, air pollution and mixed-phase microphysical schemes, case studies, and sensitivity studies;
d) interactions between atmospheric constituents (aerosols and gases and mixed clouds) and mixed-phase cloud properties, such as aerosol processing, aerosol scavenging (activation as cloud-particles, accretion onto precipitation), and cloud chemistry;
e) cloud-radiation feedbacks in the climate system involving mixed-phase clouds and change of cloud phase.
We encourage studies and discussions on current unresolved issues and future research on mixed-phase clouds.