TROPOS participates in cloud missions, which should be carried out with the new German research aircraft HALO (High Altitude and Long Range Research Aircraft, HALO). HALO offers novel opportunities due to its longe range of more than 10 000 km, its operating altitude of 15 km, and its flight duration of more than 10 hours. Besides cloud research, HALO is used for other atmospheric research like investigations of meteorology, climate change, atmospheric chemistry and dynamics, but also missions for earth observations and geophysics are planned.

  • Design of the HALO-CVI, source: enviscope GmbH

  • Manufactured prototype of the HALO-CVI, source: enviscope GmbH

  • Reseach aircraft HALO with the mounted CVI, source: Andreas Minikin/DLR

With regard to cloud research with HALO a dedicated CVI inlet (CVI technology) is developed at TROPOS (HALO-CVI) and structurally engineered by the company enviscope GmbH (enviscope GmbH), which can sample cloud drops and ice crystals when flying through atmospheric clouds. Their residual particles will then be chemically and microphysical characterized in collaboration with other research groups. The first missions where TROPOS takes part with the CVI inlet are ML-CIRRUS (cirrus clouds) and ACRIDICON (deep convective clouds). The following scientific objectives should be investigated:


(Mid-Latitude Cirrus)

  • What is the influence of emissions from civil air traffic on the formation of cirrus clouds?
  • Are there cloud-microphysical differences between cirrus clouds in clean and polluted air masses? Which role play soot and metal-containing particles?
  • How does the cloud microphysics of cirrus clouds alter during their lifetime?
  • How big is the importance of heterogeneous and homogeneous ice formation for aviation influenced and natural cirrus?


(Aerosol, Cloud, Precipitation, and Radiation Interactions and Dynamics of Convective Cloud System)

  • Do aerosol particles that serve as cloud condensation and ice nuclei have an influence on the vertical development of a young deep convective cloud?
  • Are there differences between deep convective clouds in polluted and pristine air masses with respect to freezing level and strength, type and begin of precipitation?
  • How does the vertical transport and the chemical cloud processing of aerosol particles (especially black carbon) proceed in deep convective cloud systems?

The described research with HALO is funded by the German research foundation DFG (priority program 1294; grant HE 939/25-1 and ME 3534/1-2)