Modeling of Aircraft Measurements of Ice Crystal Concentration in the Arctic and a Parameterization for Mixed-Phase Cloud

Journal Article · 15 November 2017 · Journal of the Atmospheric Sciences

DOI: https://doi.org/10.1175/jas-d-17-0037.1 · OSTI ID:1408935

Fan, Songmiao ^[1]; Knopf, Daniel A. ^[2]; Heymsfield, Andrew J. ^[3]; Donner, Leo J. ^[1]

---

1. National Oceanic and Atmospheric Administration (NOAA), Boulder, CO (United States); Princeton Univ., NJ (United States). Geophysical Fluid Dynamics Lab.
2. Stony Brook Univ., NY (United States). Inst. for Terrestrial and Planetary Atmospheres, School of Marine and Atmospheric Sciences
3. National Center for Atmospheric Research, Boulder, CO (United States)

In this study, two parameterizations of ice nucleation rate on dust particles are used in a parcel model to simulate aircraft measurements of ice crystal number concentration Ni in the Arctic. The parcel model has detailed microphysics for droplet and ice nucleation, growth, and evaporation with prescribed vertical air velocities. Three dynamic regimes are considered, including large-scale ascent, cloud-top generating cells, and their combination. With observed meteorological conditions and aerosol concentrations, the parcel model predicts the number concentrations of size-resolved ice crystals, which may be compared to aircraft measurements. Model results show rapid changes with height/time in relative humidity, Ni, and thermodynamic phase partitioning, which is not resolved in current climate and weather forecasting models. Parameterizations for ice number and nucleation rate in mixed-phase stratus clouds are thus developed based on the parcel model results to represent the time-integrated effect of some microphysical processes in large-scale models.

• Research Organization: State Univ. of New York (SUNY), Albany, NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Biological and Environmental Research (BER)
• Grant/Contract Number: SC0016370
• OSTI ID: 1408935
• Alternate ID(s): OSTI ID: 1541819
• Journal Information: Journal of the Atmospheric Sciences, Vol. 74, Issue 11; ISSN 0022-4928
• Publisher: American Meteorological SocietyCopyright Statement
• Country of Publication: United States
• Language: English