Within the international project SALTRACE scientists of the DLR Institute of Atmospheric Physics perform airborne measurements with the DLR research aircraft Falcon on the Cape Verdes and the Caribbean. The effect of dust from deserts on clouds and weather is a great uncertainty in climate prediction. The scientists aim at better understanding the climate effects of such small particles.
Satellite images show that mineral dust from deserts is transported over large distances. The dust consists of very small liquid and solid particles with a size between 1/100 and 1/1000 if the thickness of a human hair. They are called aerosol particles. Mineral dust plays an important role in the climate system because it directly influences the incident solar radiation on Earth. Moreover, mineral dust can alter the properties of clouds what also influences the radiation budget of our climate.
According to estimates an annual amount of five billion tons of aerosol particles enters the atmosphere by natural and anthropogenic processes. Dust from deserts contributes with about 2.5 billion tons, thereof 1.5 billion tons from the Sahara. With an area of nine million square kilometers – 4/5 of the area of Europe – the Sahara is the most important source of desert dust and contributes 60 percent of the global dust emission. Dust from the Sahara is periodically transported from Africa towards the west over the Atlantic Ocean to the Caribbean. In the context of global warming it is important to gain an accurate knowledge about the properties of aerosol particles from deserts in the atmosphere.
DLR press release (in German)
SALTRACE web site
Prof. B. Weinzierl