Climate change is changing the dust in the Sahara – and Europe is down

In recent years, citizens of Spain, France and the UK have looked up to see a strange sight: an orange sun and skies thick with yellow fog. These cloudy skies often produce “blood rain”, rust-laden rain that leaves a fine smear on cars and windows.

These events are caused by dust from the Sahara desert that travels thousands of kilometers across the Mediterranean. As climate change transforms the world’s largest desert, Europe finds itself reeling from an ever-changing environmental crisis.

The Sahara is responsible for more than half of the world’s dust. Under hot, dry and windy conditions, the particles are lifted several kilometers into the atmosphere and transported across the continents.

Although many go west to America, others move north to Europe, mainly between February and June. Modern plums – such as the powerful “Calima” that sometimes covers Spain – have reached as far as the North Sea and Scandinavia.

The relationship between a warming planet and dust is complex.

On the other hand, rising temperatures dry out the soil and accelerate desertification, making it much easier for the air to remove fine particles. Under conditions of extreme warming, the amount of Saharan dust raised in the atmosphere could increase by 40% to 60% by the end of this century.

However, the “dust” of the future is also dependent on spiritual processes. Some sand and dust storms in the Sahara are actually very rare and have decreased significantly over the past two decades. On the other hand, this is due to the increase in vegetation in the Sahel region on the southern border of the Sahara. But it’s also down to a reduction in surface winds in general, and changes in certain types of extreme weather.

Health risks and economic consequences

For Europe, the impact is not just beauty. Saharan dust can seriously damage air quality, pushing particulate matter levels above health standards. These fine particles, known as PM10, can enter the lungs, causing asthma and heart problems. In Spain and Italy, case studies show that Saharan dust can account for 44% of deaths related to PM10 pollution.

Dust also carries additional costs. When it settles on the snow in the Alps it darkens the surface and makes it unable to reflect sunlight, accelerating melting. It can reduce the efficiency of solar panels and disrupt aircraft and road traffic by reducing visibility.

What to do with dust

Responding to this growing cross-border problem means working at the source and in the affected areas.

In the Sahara and its surroundings, it is important to prevent disturbance of unstable soil. Overgrazing, river silting and land dumping can all increase dust production. To stabilize the soil, measures include replanting, maintaining the flow of rivers and protecting the biodegradable “biocrust” of bacteria, moss and other organisms that bind the top few millimeters of desert soil and make a natural shield against wind erosion.

In Europe, the focus is on preparedness. Early warning systems provide forecasts up to 15 days in advance, allowing health authorities to issue warnings for vulnerable people to stay indoors. Simple measures, from improved building ventilation to creating more green urban spaces, can also reduce exposure.

For decades to come, the “dust belt” of the Sahara will remain a visible sign of life on our planet. But technology and prediction alone will not be enough to solve the problem.

Dust does not respect borders, so controlling it will require strong international cooperation – and binding agreements – on everything from managing river basins to preventing lake beds from drying up, to public health responses across Europe. Whether orange skies remain a curiosity or become a normal feature of European life, governments across Europe and Africa must take this shared risk seriously.