The High Altitude Research Station Jungfraujoch
- Continuous aerosol measurements are done with a heated inlet (25°C) designed to evaporate cloud droplets and small ice crystals at an early stage of sampling (i.e. sampling both cloud residual and interstitial particles).
- During campaigns, an interstitial inlet is operated. Here, a PM2-cyclone is used to sample only the non-activated aerosol (i.e. no cloud droplets or ice crystals).
- Currently an ice selective inlet is developed. It will also allow the extraction of small ice particles in mixed-phase clouds for the physico-chemical characterization of tropospheric ice nuclei.
Throughout the year, the station is within clouds about 40% of the time. This offers the unique possibility to investigate the climate relevant properties of clouds and their formation processes, particularly those of mixed-phase clouds where supercooled cloud droplets and ice crystals coexist. The aerosol monitoring and research activities at Jungfraujoch are performed within the Global Atmosphere Watch (GAW) program of the World Meteorological Organization. The research activities and have been and are embedded in numerous EC projects, such as EUSAAR, EUCAARI, GEOMON, and most recently ACTRIS.