Largest cloud simulator put into service
The world's largest cloud simulator has created its first artificial cloud at the Leibniz Institute for Tropospheric Research in Leipzig. The scientists are promising Leipzig Aerosol Cloud I nteraction Ssimulator (LACIS) new insights into how clouds form and how they affect climate.
The simulator consists of a 16 meter high tower, in the heart of which - a long vertical double-walled flow tube - controllable clouds are created by combining water droplets with dust particles. The cloud is generated in the inner tube, which is only three millimeters thick, while in the outer tube, selectable but highly stable climate conditions can be set in sections. At the top of the tube, condensation nuclei of known size, number and composition (e.g. mineral dust particles, soot or common s alt crystals) are blown in together with moist air.
The flowing mixture is cooled down until the water vapor condenses on the cores and drops form. Depending on the further temperature and humidity conditions on the journey through the flow tube, the droplets continue to grow, dry off again or freeze. Along the way, the size and shape of the cloud elements are optically measured in order to then be able to describe their growth behavior mathematically.
In this way, scientists can examine practically in a test tube how clouds form and how they change, above all, as a result of air pollution. Since not all cloud processes can be simulated in the laboratory, LACIS is supplemented by a miniaturized cloud laboratory that is immersed in atmospheric clouds hanging from the helicopter.
LACIS could, among other things, improve weather forecasting, as emphasized by the Federal Ministry of Research. The federal government financed half of the three million euro project, the rest came from the state of Saxony.