Skies across southwestern Europe turned orange this week as an exceptional Saharan dust episode blanketed the region and the dust moved northwards to reach as far as the UK, Denmark and Russia.
Concentrations of particulate matter were exceptionally high. As the large plume travelled across the Iberian peninsula, a sharp rise was recorded in inhalable particles of up to 10 microns in diameter (PM10), in excess of the 50 micrograms per cubic metre that is considered safe by the World Health Organization.
The information from the Copernicus Atmosphere Monitoring Service showed degraded air quality across large parts of Spain, Portugal and France related to the Saharan dust transport. The Balearic government’s Atmosphere Service also advised the public to limit physical activities outdoors on Tuesday and Wednesday because of the high dust concentration.
Saharan dust episodes are common in the Mediterranean and the Atlantic, particularly in spring.
In 2021, an early dust event gave the snow-capped mountains of the Alps an orange tinge.
In January this year, the year’s first “Calimas” — dust storms in the Canary Islands region originating in the Sahara desert — spread northwards as far as Iceland.
Another ongoing event started earlier this month, with dust travelling across Cape Verde and over the Atlantic to the Caribbean and South America.
Saharan dust provides an estimated 22,000 tons of phosphorus, an essential nutrient, to the Amazon rainforest each year.
Some studies predict that climate change will result in even more intense Saharan dust storms in the future, which could affect public health because of reduced air quality.
Where climate change meets business, markets and politics. Explore the FT’s coverage here.
Are you curious about the FT’s environmental sustainability commitments? Find out more about our science-based targets here