Freezing fog microphysics and visibility based on CFACT Feb 19 case

Durmus, O., Gultepe, I., Sen, O., Pu, Z., Pardyjak, E. R., et al. (2025). Freezing fog microphysics and visibility based on CFACT Feb 19 case. Remote Sensing, doi:https://doi.org/10.3390/rs17152728

Title Freezing fog microphysics and visibility based on CFACT Feb 19 case
Genre Article
Author(s) O. Durmus, I. Gultepe, O. Sen, Z. Pu, E. R. Pardyjak, Sebastian Hoch, A. Perelet, A. G. Hallar, G. Carrillo-Cardenas, S. Durmus
Abstract The objective of this study is to analyze microphysical parameters affecting visibility parameterizations of a freezing fog case that occurred on 19 February 2022, during the Cold Fog Amongst Complex Terrain (CFACT) project conducted in a high-elevation alpine valley in Utah, USA. Observations are collected using visibility, droplet spectra, ice crystal spectra, and aerosol spectral instruments, as well as in-situ meteorological instruments. Particle phase is determined from relative humidity with respect to water (RHw) as well as ground cloud imaging probe (GCIP), ceilometer (CL61) depolarization ratio, and icing accumulation on the platforms. Results showed that freezing droplet density can affect visibility (Vis) up to 100 m during Vis less than 1 km. In addition, increasing volume can lead to up to a 2 μm increase in droplet radius due to a change in the chemical composition of aerosols from Sodium Chloride (NaCl) to Ammonium Nitrate (NH4NO3). Overall, comparisons suggested that Vis parameterizations are highly variable, and freezing fog conditions resulted in lower Vis values compared to warm fog microphysical parameterizations. Furthermore, riming of freezing fog conditions can lead to more than 50% uncertainty in Vis. It is concluded that changing aerosol composition and freezing fog droplet density and riming can play a major role in Vis simulations.
Publication Title Remote Sensing
Publication Date Aug 7, 2025
Publisher's Version of Record https://doi.org/10.3390/rs17152728
OpenSky Citable URL https://n2t.net/ark:/85065/d7zs3215
OpenSky Listing View on OpenSky
EOL Affiliations ISF

< Back