The measurements in 2017 at the Jungfraujoch station aimed to confirm the existence of these vertical fluxes from the surface and their contribution to the measured number concentration of ice particles. For this goal, the well-adapted and previously used system of a rotation wing that points instruments into the mean wind field was reused in 2017. The list of instruments involved a 3 View-Cloud Particle Imager (3V-CPI). A combined probe of a two-dimensional stereoscopic (2DS) shadow imaging probe and a cloud particle imager (CPI). Furthermore, a cloud droplet probe (CDP) on the wing measured size distributions of liquid droplets, providing a combined particle range of 3 to 1250 μm.
Ice crystal fluxes were calculated using eddy covariance calculated from the wind direction and speed near the inlet of the 3V-CPI. This provides data for the first particle flux calculations for particles over the range of 3 to 1250 μm. The first results show the presence of increased upward but also downward fluxes of both liquid supercooled droplets and larger ice particles which were often composed of pristine plate crystals.
Keywords Schledewitz, Lloyd, Choularton, Gallagher, Eddy-Covariance, Fluxes, Number Concentrations, Cloud Microphysics, Orographic Clouds, Meteorology
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