A Dust Storm On European Ski Slopes?

Dust from the Sahara desert at a ski resort in 
Switzerland last week. 

 A huge blast of dust from the Sahara Desert swept through large parts of Europe this week, turning the sky and the snow on ski slopes orange.  

Dust from the Sahara does find its into Europe pretty frequently if there's a good surge of southerly winds from Africa. 

This one, though, carried much more dust than usual.  

According to the Washington Post's Capital Weather Gang:

"But it's rare for such episodes to be so widespread or intense. In addition to the dusky skies, sand may accompany rainfall in some locales, making for a shower of gritty mud."

At Spanish ski slopes, it looked like the skiers were making turn on reddish brown sand. Only when the skiers made their turns did the white snow underneath the sand make an appearance. 

Saharan dust and sand is more mobile than most desert soils, so it gets around. Wapo/Capital Weather Gang likens it to the texture of makeup, really lightweight and powdery. It really can go anywhere. 

Strong trade winds in the summer bring dust from the Sahara all the way to the Americas, creating yellow, hazy sunsets to places like Miami, New Orleans, Houston, Caracas and Rio De Janeiro. 

When the dust lands in South America, that's a good thing. It's loaded with dead microorganisms that contain lots of phosphorus.  It turns out the dust is a critical fertilizer for the Amazon rain forest.

The annual dump of 22,000 tons of phosphorus a year on the Amazon from Sarah dust is about equal the amount lost annually to rain and flooding, so it's a nice balance.

The Saharan dust that winds up on the mountain summits and ski areas of Europe isn't such a great thing, at least in the era of climate change.  And it's not great for the lungs of Europeans trying to breathe the air.

As the Associated Press reports, air pollution alerts were issued in Spain, Portugal and parts of France. Rain in Paris and London left blobs of muddy Saharan dirt on cars. 

In the mountains, the reddish grit obviously makes the snow a darker color than the gleaming white you'd expect.

With the increasing sun angle in the Northern Hemisphere this time of year, the discolored snow will absorb more of the sun's rays that white powder, which reflects the sun's heat back out to space.

This situation could lead to an earlier melt season, getting rid of the season's snowpack earlier in the summer. If it's a hot European summer, the dust could eventually accelerate the erosion of long-standing but melting glaciers in places like the high Alps. 

The dust will be a very small player in the climate change game, but even tiny setbacks don't help.