By Sameer Kolpekwar
In what appears to be an event straight out of science fiction, parts of Eastern Europe looked like Mars after being covered in orange-tinted snow. Areas such as the Sochi region in Russia and parts of Bulgaria and Romania reported orange snow. The orange snow was first spotted on March 23 and it came to light after tourists shared photos on social media and joked about being able to ski on Mars.
What is orange snow?
When atmospheric temperatures are near freezing and the clouds contain enough moisture conditions are suitable for snowfall. However, if the ground temperature is not cool enough, snowflakes melt and make their surroundings cooler. Normally, snow is white in colour however in some cases while falling on the ground some matter may mix with the snow. If dust and sand present in the air mix with the snowflakes they can get an orange-red tint, which is called orange snow. Cases of orange snow primarily occur in Europe. According to BBC, Europe witnesses a case of orange snow every five years.
According to various meteorologists, sand and dust from Sahara desert were responsible for the orange snow in the Sochi region and nearby areas. Tyler Roys, a meteorologist with Accuweather, stated that the phenomenon started when strong winds and thunderstorms travelled further south than expected into Northern Africa and created conditions that kicked up dust and sand in the Sahara. The dust mixed with the cloud cover somewhere near the Black Sea region and travelled over Europe before finally settling down in the Sochi region. The Athens Observatory reported that it was one of the largest transfers of sand from the Sahara ever.
Identifying the cause
Since Europe experiences orange snow periodically, it was quite easy to determine the cause. The reasons for the latest orange snowfall came to light after NASA’s satellites acquired images over Eastern Europe and Northern Africa. The images were taken by the spectroradiometer module and showed a dust cover over eastern Europe on March 24. More instances of dust blowing across the Mediterranean were seen on 26 March.
According to Tyler Roys south and south-west winds created a low-pressure region that led to the flow of dust in Europe. While Eastern Europe reported orange snow, parts of Greece experienced a large amount of sand in the air with dust causing reduced visibility and people reporting they could taste sand in the air. The flow of dust was consistent with the fact that large dust storms occur this time of year in the Sahara, however, this particular dust storm was quite stronger than expected.
Similar instances have occurred in the past. In 2007, Siberia experienced orange snow falling in early February. While the recent orange snow over Sochi and other parts was harmless, the Siberian orange snow was reportedly smelly, oily to touch and contained almost four times the normal amount of iron. However, the causes for the Siberian orange snow were industrial pollution and missile testing whereas the recent orange snow was completely due to natural causes.
According to Mr Bowles of the UK Met Office, the flow of dust and sand from the Sahara to Europe is a periodic occurrence. There are days when sand and dust creates a light cover over vehicles in England. Last year, Hurricane Ophelia picked up sand and dust which led to a light tint to the skies of Europe. While the orange snow was in full force over the weekend of March 24, meteorologists do not expect it to stay strong.