Saharan Dust Makes Orange Snow
In late March 2018, the people of Eastern Europe and Russia found their snow cover had a distinctly orange tint.
The color came from vast quantities of Saharan dust that was picked up by strong winds, lofted over the Mediterranean Sea, and deposited on Bulgaria, Romania, Moldova, Ukraine, and Russia. Skiers in the Caucasus Mountains snapped photos that looked like they could have come from the Red Planet.
The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite acquired a natural-color image of the dusty snow in Eastern Europe on March 24, 2018. The MODIS instrument on the Terra satellite acquired the second image, a natural-color view of dust from North Africa blowing across the Mediterranean Sea on March 26, 2018. Dust storms were still raging on March 27, as shown by another Terra image of the Black Sea region.
In Greece, Crete, and Cyprus, the airborne particles significantly reduced visibility for days, and people described tasting dust as they walked outside, news media reported. Authorities cautioned children, the elderly, and people with respiratory diseases to stay indoors as much as possible. According to several news accounts, the Athens Observatory called this event one of the largest dust deposits on record in Greece.
South and southwest winds associated with a low-pressure weather system appeared to fuel the flow of dust into Europe. Those dust plumes were visibly mingled with cloud cover over the Black Sea in a March 23 image from the Suomi NPP satellite. Some of the airborne dust mixed into the snow and rain that fell on the region on March 23-24. The Ozone Mapping & Profiler Suite (OMPS) on Suomi NPP detected high levels of airborne aerosols over the region from March 20-25.
Dust storms are common in the Sahara in the springtime, as the weather changes with the seasons. Large dust events tend to occur about every five years, though multiple observers described this one as particularly intense.
