First results from the field campaign on freezing nuclei in mixed-phase clouds

Clouds in the atmosphere are composed of water droplets and ice crystals. At a temperature of above 0 °C, warm clouds are composed only of water droplets and below 0 °C, where the preferential aggregation state of water is the solid state, ice, the prevailing clouds are the so-called cold clouds. While clouds made of pure ice occur at temperatures below -38 °C, clouds in mixed phase are found at temperatures between -38 °C and 0 °C, where ice crystals and water droplets water can coexist due to the supercooling ability of water. In mixed-phase clouds, the freezing process of water droplets is facilitated by aerosol particles that will lead to the nucleation of the first ice crystals.

During the field campaign in Norway, master student Alex Vlad, learn from Norwegian and Romanian seniors how to perform investigations on the formation of the freezing nuclei in mixed-phase clouds. Some of the results were analyzed and included in his Dissertation thesis. Alex defended his dissertation on May 26, 2023 at the Faculty of Physics of the University of Bucharest.