Atmospheric clouds are complex systems the influence of which is global concerning the formation of precipitation and the energy budget. Via the emission of gases and particulate matter (the products of combustive processes are especially important in this context), human activity alters the formation and characteristics of clouds and exerts an influence on the spatial distribution and intensity of precipitation and on climate in general.
Given their complexity and their irregular appearance in inaccessible locations, atmospheric clouds are difficult to investigate. As a consequence, many of the processes associated with cloud formation and precipitation are still inadequately understood, and are not yet quantifiable with sufficient exactitude. They must, hence, be investigated in appropriate experiments. Key processes in this connection are the formation of condensation droplets on the natural and anthropogenic particulate matter available in the atmosphere, as well as the freezing of cloud droplets.
In order to investigate these key processes under clearly defined and controllable conditions, the "Leipzig Aerosol Cloud Interaction Simulator" (LACIS) was built at the Leibniz Institute for Tropospheric Research in Leipzig. In the form of an 8 m long vertically oriented flow tube, LACIS was configured such that atmospheric conditions for particle and droplet growth in relation to water vapour saturation and to time can be imitated as closely to reality as possible.
For further information on setup, measurement principle, and experiments at LACIS click here.
