Tiny grains of sand in the Middle East can produce trouble for both man and machine in the area: sandstorms.
The swirling winds that often rake the area can produce some of the most severe sandstorms on Earth, storms that are fairly easy to predict but ones that can bring any kind of activity to an immediate halt, says Texas’ chief weatherman.
“This time of year can be a rough time in Iraq because the winds tend to pick up and when they do, the result is a sandstorm that can make conditions unbearable and stop almost any kind of movement,” said John Nielsen-Gammon, professor of atmospheric sciences at Texas A&M and Texas State Climatologist.
Sandstorms are caused by strong winds that occur in desert or semi-arid regions, and they carry thick clouds of dust and sand, often reducing visibility to near zero.
Winds ranging from 20 to 50 mph are not uncommon in the region, and the resulting sandstorms can last from several hours to a full day, Nielsen-Gammon said.
“Most of the time, sandstorms affect only the SANDSTORM air from about 1 to 3 miles high, so airplanes flying above that range are okay,” he said. “But on the ground, the visibility can be just a few feet to near zero. Sand moving at near 50 miles can be a real nightmare.”
Sandstorms and their accompanying dust can clog up anything mechanical, from a soldier’s M-16 rifle to an F-16 fighter jet. Once the sandstorm has passed, a thorough cleaning of just about anything is required.
Nielsen-Gammon says there are two types of sandstorms. One is the result of severe thunderstorms that create strong winds. This type is called a “haboob,” an Arabic word meaning “blowing dust.”
The second type is the one many Americans are familiar with. It is caused by a curving of the jet stream, which brings strong winds to the Earth’s surface.
“It causes the kind of sandstorms you see in West Texas,” Nielsen-Gammon said. “Sandstorms tend to be worse during the daytime because the ground is heated up by the sun and the dust can be carried greater distances.”
Masks are a necessity when facing a sandstorm, Nielson-Gammon said.
Though the Middle East has its share of sandstorms, Nielsen-Gammon says the worst cases occur in China and Mongolia, where a “yellow rain” effect can be seen.
“There’s so much sand in the air that it changes the color of raindrops, and there appears to be yellow rain falling from the sky,” he said.