Weather Higher concentrations of Saharan dust are expected on Friday
Saharan dust clouds the air and turns it yellowish at high concentrations: view from Pizol on March 29, 2024.
Image: Keystone
On snow and glaciers, Saharan dust (here on the Simplon Pass) reduces radiation and thus accelerates melting.
Image: Keystone
Saharan dust clouds the air and turns it yellowish at high concentrations: view from Pizol on March 29, 2024.
Image: Keystone
On snow and glaciers, Saharan dust (here on the Simplon Pass) reduces radiation and thus accelerates melting.
Image: Keystone
A strong southerly current is currently blowing Saharan dust towards Switzerland. After crossing Spain and France, the concentration in Switzerland is expected to reach a peak on Friday. This means that the first denser Saharan dust of this year is on its way.
20.03.2025, 11:56
SDA
The southerly flow has formed between an extensive high over Eastern Europe and an Atlantic low, as the weather service Meteonews reported on Thursday. The current reached as far as North Africa and took the Sahara dust with it.
Harbingers of the dust were already expected on Thursday evening. As the Atlantic depression approaches, south to south-westerly winds will intensify. MeteoSwiss is therefore expecting larger dust loads over the course of Friday until the Saharan dust concentration reaches a maximum in the evening.
Saharan dust occurs several times a year in Switzerland. The air becomes cloudy and turns yellowish in high concentrations. According to Meteonews, 60 percent of Saharan dust consists of quartz. According to studies, it is less harmful to health than traffic-related particulate matter, for example.
When precipitation falls, so-called blood rain occurs. On snow, the yellowish-brownish dust reduces reflection, causing the snow to melt faster. The same happens on glaciers.
Saharan dust also has positive effects: According to Meteonews, the mixture of quartz sand, clay, goethite, gypsum and fossilized algae is a fertilizer. In early summer, trade winds carry Saharan dust across the Atlantic to the Amazon region. Without Saharan dust, the rainforest there would not exist.
The dust also acts as a solar filter, inhibiting the warming of the sea surface, which in turn deprives hurricanes of their energy.
