Europe struck by desert dust
Hot, dry deserts can feel a million miles away, especially in the typically damp European springtime. But that doesn’t mean we can live without being affected by these vast arid regions. This week, skies across Europe are turning orange as plumes of dust from the Sahara Desert are transported over the Mediterranean Sea. And unfortunately, desert dust leaves its mark in other ways too, from reducing solar energy generation to leaving cars and clothes covered in a layer of dirt.
In dry areas where dirt particles are loosely bound to Earth’s surface, dust can be blown up into the air. There, the particles may be suspended for a week or more, during which time they can be swept thousands of kilometres by the wind. These dust particles have the possibility to significantly impact weather, climate, visibility, energy production and human and plant health.
To help scientists study its impacts, and to assist environmental agencies and energy companies in analysing the potential for disruption, the Copernicus Atmosphere Monitoring Service (CAMS), which is implemented by the European Centre for Medium-Range Weather Forecasts on behalf of the European Union, provides global forecasts of the amount of dust in the atmosphere. These take into account the emission, transport and deposition of dust. Produced twice a day, the forecasts are created by combining satellite observations with a computer model to predict how the distribution of dust plumes will change over the next five days.
While dust suspended in the atmosphere directly affects various business sectors and individuals, the settling of this dust has its own implications, which is why CAMS is now investigating how to accurately forecast this separately. This is complicated, because it not only relies on a good forecast of dust emission and transport, but is affected by factors such as rainfall. CAMS is currently working with various potential users of such a forecast to explore whether the service could provide it sufficiently accurately, and if so, what would be the best way of doing so.
One sector that already benefits from CAMS forecasts of airborne dust is the solar energy industry, which is interested in knowing when dust will block sunlight, as this impacts energy production. Dust also reduces energy output when it settles on solar panels, so deposition forecasts would help solar plant managers anticipate and organise the cleaning of solar panels, as well as assisting them with finding the optimal location for a solar plant.
The settling of dust can affect other economic sectors, such as agriculture; when dust lands on leaves, it can limit photosynthesis. And when dust lands on railway tracks and large overhead lines, train operations are affected. Both the agriculture and transport sectors would benefit from CAMS forecasts of dust deposition.
“In the future, we hope to attract experts who can process the information we provide to make it useful for a whole range of industries that are affected by the deposition of desert dust,” explains CAMS Principal Scientist, Johannes Flemming.
Knowledge of dust deposition could also be used by entities that monitor air quality and enforce mitigation measures. For example, it can be useful to pour water on roads before dust falls to the ground, so that cars don’t disturb the settled dust and affect the quality of the air we breathe. But to use this as an effective mitigation measure, entities need to be able to predict very precisely when and where dust will land.
Individuals could also benefit from dust deposition forecasts. When heavy settlement is predicted, cars could be placed under cover, and clothes could be dried inside. Possibly most importantly, individuals susceptible to respiratory and cardiovascular issues could more easily avoid inhaling irritating dust particles.
“The visible nature of dust demonstrates that sand particles can travel a long way, and makes the point that air pollution is not local,” explains Richard Engelen, Deputy Head of CAMS. “But aside from this, dust can be quite devastating for African and Mediterranean countries. It gets into houses, into lungs, can close airports and roads, and with climate change potentially causing deserts to grow, desert dust in the atmosphere will only increase. That’s why its vital to have good forecasts.”