Desert aerosol is constantly transported from the surface of the earth into the atmosphere, and from there over long distances. What influence this dust has on the earth’s radiation balance is virtually unknown. In view of global climate change and local desertification processes, it is accordingly important to obtain precise knowledge about the characteristics of desert aerosol particles in the atmosphere.
The Sahara is a huge reservoir for the introduction of dust into the atmosphere, which can be carried as far as the Americas in air currents. In the SAMUM (Saharan Mineral Dust Experiment) project, the optical effects of mineral dust will be investigated in detail. A team of eight national institutes will take in-situ aerial as well as remote sensing measurements and combine them with models to derive information on the spatial distribution and transport of these dust layers as well as their physical and chemical composition.
The IMF Atmospheric Processors department is providing radiative transfer simulations for the SAMUM project as well as databases on the optical characteristics of mineral dust particles. The department is also involved in taking infrared ground-based measurements off the west coast of Africa on the Cape Verde Islands to characterize spectral radiation densities beneath the dust cloud.