Clouds in-situ
During the RACLETS campaign, in-situ measurements of clouds were conducted using two measurement platforms owned by ETH Zurich: HoloBalloon and HoloGondel. HoloBalloon, a tethered balloon system, was launched at Davos Wolfgang at an elevation of 1630 m above sea level (a.s.l.) and ascended up to 800 m above ground. HoloGondel was mount on the upper section of the Gotschnabahn cable car, running between Gotschnaboden (1779 m a.s.l.) and Gotschnagrat (2285 m a.s.l.).
Both platforms were equipped with a holographic imager HOLIMO to measure the cloud microphysics. HOLIMO was used to image cloud particles in a size range between 6 μm and 2 mm in a three-dimensional sample volume. Cloud droplets and ice crystals were discriminated above 25 μm based on the shape of their 2D shadowgraph. The products are phase resolved particle size distributions, concentrations, water contents and spatial distribution of the cloud particles. In addition to HOLIMO, the size distribution between 0.3 and 20 μm was measured by an optical particle counter covering the larger aerosol particles and smallest cloud droplets in addition to meteorological parameters (temperature, relative humidity, atmospheric pressure).
Instruments to measure aerosol concentrations, meteorological parameters, wind profiles/velocities, precipitation and the CloudNet station were close to the location where HoloBalloon and radiosondes were launched.
Images 1 and 2: HoloBalloon at Davos Wolfgang. © Annika Lauber
Images 3 and 4: Hologondel mounted at Gotschnabahn. © Annika Lauber
Additional Info
| Field | Value |
|---|---|
| parent | RACLETS Field Campaign |