“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.”
Rein Haarsma, a climate researcher at the Royal Netherlands Meteorological Institute, cautioned against ascribing the white-capped dunes to changing temperatures because of pollution.
“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.