Snow in the Sahara Desert
Up to 16
inches of snow has fallen on a town in the Sahara desert after a freak winter
storm hit the area. This is the third time in 37 years that the town of Ain
Sefra in Algeria has seen snow cover the red sand dunes of the desert. Ain
Sefra is 1078 m above sea level, surrounded by the Atlas mountains. The highest
temperatures can reach more than 500C. Despite its altitude, it is
extremely rare to see snow in the town, and it is normally six to 12 degrees
Celsius in January.
The first
time snow was seen in Ain Sefra was on February 18, 1979 but the snow storm
lasted just half an hour. The second was on December 19, 2017 and the third was
on January 7, 2018. The flurry lasted for half an hour and the snow stayed on the
ground for a day, piled up to 40 cm (16 inches). By 5:00 PM, the snow has
melted. Children made snowmen and even sledged on the sand dunes.
The
weather pattern came from North America and Eastern Canada, sweeping up over
Canada, going across the Atlantic and Europe, and creating the conditions in
the Sahara. Cold air was pulled down south in to North Africa over the weekend
as a result of high pressure over Europe. The high pressure meant the cold
weather extended further south than normal.
The Sahara
Desert covers most of Northern Africa and it has gone through shifts in
temperature and moisture over the past few hundred thousand years. Another
cause for this occurrence, a source mentioned, is the climate change – the global
warming – although there are still some controversy of this possibility.
The global
warming has caused the Arctic to melt. The warmer the ocean surface, the more energy
that is available to intensify these storms and the more moisture there is in
the atmosphere – moisture that is available to form precipitation. As the winds
wrap around in a counter-clockwise manner, they bring all of that moisture northwest,
where it is chilled and ultimately falls not as rain but snow, lots of snow.
But, a
statement made by Rein Haarsma,
a climate researcher at the Royal Netherlands Meteorological Institute,
cautioned against ascribing the white-capped dunes to changing temperatures
because of pollution.
The Sahara
is as large as the United States, and there are very few weather stations,” he
added. “So it’s ridiculous to say that this is the first, second, third time it
snowed, as nobody would know how many times it has snowed in the past unless
they were there.”
“It’s rare, but it’s not that rare,”
said Mr. Haarsma said in an interview. “There is exceptional weather at all
places, and this did not happen because of climate change.” The snow fell in the Sahara at
altitudes of more than 3,000 feet, where temperatures are low anyway. But Mr.
Haarsma said cold air blowing in from the North Atlantic was responsible.
