Low to moderate air pollution levels expected as Saharan dust sweeps UK

The southerly air flow from Sahara, Africa brought a thin band of dust over parts of UK on December 16, 2015, Met Office reports. Numerous monitoring stations have detected the dust just above the surface since. The conditions are expected to last only a couple of days as the new cold front sets in.

The air particles from the Sahara dust are expected to bring low to moderate air pollution levels across the UK until December 20.  A cold front forecast to move over the UK on December 17 will sweep the region with the southwesterly flow of cleaner air and lower the pollution levels by December 18. On the following day, southerly winds might spread additional dust bands across portions of England and Wales, while lower pollution levels will settle in again on December 20. Expected rainfall could leave dust deposits on the grounds of affected areas.

Saharan dust gets lifted from its place of origin by strong winds and can reach very high altitudes. Winds, mixing air masses can carry it across thousands of kilometers of distance. Dust particles can easily get caught in rain droplets, and when the rainfall water evaporates, layers of dust can be found on ground surfaces. Their presence in the atmosphere can also provide spectacular sunset views.

Although the phenomenon of the so-called, blood rain has, on rare occasions been reported across the globe, it requires high concentration of red dust particles in the atmosphere, and seems very unlikely to happen on this occasion.

Featured image: Sahara dust reaching UK – March 2014. Credit: UK MetOffice