The High Altitude Research Station Jungfraujoch

The High Altitude Research Station Jungfraujoch is located in the Swiss Alps in the center of Europe and is the property of the Foundation HFSJG. It comprises several laboratories, a mechanical workshop, a library, a dining and recreation room, a kitchen, ten bedrooms, and the custodians’ apartments. The Jungfraujoch is the highest research station in Europe that is accessible all year round by rail and it is the only accessible observation point in Europe with adequate infrastructure that is within the free troposphere most of the year. The special geographical situation offers the opportunity to monitor European background concentrations but also to investigate the transport of anthropogenic pollutants from the boundary layer to the free troposphere. The site is therefore of utmost importance for ground-based observations of the lower free troposphere. The research on aerosols as well as on trace gases (i.e. greenhouse gases, reactive air pollutants) are among the most comprehensive ones worldwide.

Our group conducts aerosol measurements in the Sphinx Laboratory which is located on an exposed mountain col at an altitude of 3580 meters. Ambient air is sampled from different inlet systems:

• 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.

Comparing the response downstream of the different inlets provides insight in the fractionation of aerosol particles between the cloud phases (liquid, ice) and the interstitial phase.

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.

As part of the transnational access (TNA) activity, ACTRIS offers opportunities to researchers or research teams to access the Jungfraujoch research facilities with an excellent combination of advanced instruments and expertise, using state-of-the-art equipment for measurement campaigns and instrument testing. ACTRIS supports training of new scientists in order to conduct high-quality research and contributes the scientific community to exchange knowledge and experience and to work towards future common projects and objectives. More information on TNA is found here.

Click here for information on the continuous aerosol measurement programme.

Click here for information on the intensive measurement campaigns.

Please direct questions and/or comments about PSI’s activities at Jungfraujoch to Martin Gysel Beer or Urs Baltensperger.