An “exceptional” episode of Sahara dust degrades air quality in Western Europe

Photo: Valery Hache Agence France-Presse Air quality has been affected in the south of France, in Nice, by dust winds coming from the Sahara.

France Media Agency in Paris

April 8, 2024

• Europe

An “exceptional” quantity of dust from the Sahara has been rising over Western Europe since Saturday, a phenomenon whose frequency has been increasing in recent years, with harmful consequences on air quality, the European observatory warned on Monday Copernicus.

This episode, the third in two weeks, of “large-scale transport of Saharan dust across Europe” has lasted since April 6 and has notably resulted in “high concentrations of PM10” (particles of diameter less than 10 micrometers) “in the Iberian Peninsula as well as in parts of France and Germany”, sometimes exceeding the European daily normal, according to the Copernicus Air Quality Monitoring Service (CAMS).

“Daily maximum CAMS forecast values ​​for PM10 showed significant concentrations at surface level, exceeding the EU 24-hour average exposure threshold of 50 micrograms per cubic meter (µg/m3) in some of the affected regions,” Copernicus said in a statement.

These concentrations will continue to increase in the coming days thanks to atmospheric circulations which prolong this transport, warns CAMS.

The dust plume has already crossed most of the Iberian Peninsula to reach southeastern France and Germany, as far as Scandinavia, notes Copernicus.

“This latest episode of Saharan dust is the third of its kind in the last two weeks and is linked to weather conditions which have led to warmer weather across Western Europe in recent days,” said Mark Parrington, a senior scientist. from CAMS.

“Although it is not uncommon for Saharan dust plumes to reach Europe, the intensity and frequency of such episodes has increased in recent years, which could potentially be attributed to changes in atmospheric circulation patterns,” he adds.

In France on Sunday, the regional air quality observatory Atmo Occitanie warned of degraded air quality, with five departments – Haute-Garonne, Gers, Ariège, Pyrénées- Orientales, Hautes-Pyrénées — at level 4 (bad), on a scale from 1 (good) to 6 (extremely bad).

Exposure to high levels of PM10 can have various effects on health, including triggering asthma attacks or allergies and aggravating certain respiratory or cardiovascular pathologies, particularly in vulnerable people (pregnant women, children, the elderly or immunocompromised).

The Sahara is the largest source of mineral dust, releasing between 60 and 200 million tonnes per year. If the larger particles fall quickly to the ground, the smaller ones can be transported thousands of kilometers and reach all of Europe.