Aerosol and Cloud Physics

Upper Troposphere / Lower Stratosphere (UTLS)

  • Airborne measurements, in particular at up to Stratospheric altitudes (~20 km) concerning aerosol number concentration and size distribution, chemical composition and morphology.
  • Sources, new particle formation and transport processes of aerosol.
  • Aerosol interaction with atmospheric water vapor and trace gases.
  • Aerosol spatial distribution.
  • Cloud particle microphysical properties, such as cloud particles size distributions and concentration, shape and phase in mixed phase clouds, ice clouds, subvisible cirrus, polar stratospheric clouds, volcanic plumes, clouds in the outflow of Mesoscale Convective Systems.


  • Airborne and ground-based (mountain-top) holographic measurements of cloud particles yielding a three-dimensional position, size and shadowgraph of each ice particle and cloud droplet in a local ~10 cm3 sample volume.
  • Holographic measurements of cloud particles in the vertical wind tunnel to observe cloud particle collision and coalescence.
  • Measurements of the structure (spatial distribution) of cloud droplets and filaments of dry air at cloud top using a simulated stratus cloud in the laboratory.
  • Development of holographic instruments and particle-hologram analysis technique.

Atmospheric Hydrometeors

  • Ice nucleation
  • Growth of ice particles by riming
  • Shape, oscillation, collision and internal circulation of raindrops
  • Uptake and retention of trace gases by raindrops and ice particles