Wednesday, January 30, 2013

Haboob--A dust storm by another name

Dust Storms have always occurred and still occur, although not as frequently or as destructively as occurred during the Dust Bowl. 

These storms are now called haboobs, perhaps because the term ‘dust storm’ has become so closely associated with the Dust Bowl, a time people would like to forget.

Haboob is an Arabic word. The storms of blowing sand and dirt occur in the Sahara and the Arabian Peninsula, central Australia, and the southwestern United States. Most people don't know that Phoenix has three haboobs a year, on average. Above is a photo of a haboob rolling over Phoenix.

Most often haboobs are triggered by the downburst of wind ahead of a thunderstorm. Sixty miles per hour winds lift the sand up to 10,000 feet high. Haboobs last two to three hours and may be followed by rain. If the droplets pass through the dust, they land as wind-driven mud balls. 

Look at this incredible time lapse photography by photographer Mike Olbinski of a massive haboob that struck Phoenix, Arizona on July 5, 2011.  http://www.youtube.com/watch?v=vYnuzoH5oBA

Haboobs are also triggered by cold fronts blowing across dry land. With the widespread drought in Texas and surrounding states in the last few years, the number of haboobs is increasing.  Could it be another Dust Bowl in the making?

Why were the dust storms so much worst during the 1930s?

A couple of factors contributed to the increased frequency and severity of dust storms during the 1930s. Some were man's doing and some were nature doing what she always does--blow.

Droughts have always occurred across the Great Plains. For eons, the prairie grasses, with their roots often five feet deep, held the thin soil in place through even the driest periods. In fact, in the 1800's the region was known as the Great American Desert until the railroads convinced mapmakers and others to change the name to the Great Plains. Hard to sell land in the desert.

In the 1920's, farmers on the southern prairie used their new gas-powered tractors to plow up land the size of Ohio and plant shallow-rooted crops like corn and wheat. The ranchers of the time tried to warn the farmers that they were turning the soil 'wrong side up.'  But believing in progress, the farmers did not listen.

In the 1930s, drought hit, crops withered, and the open, disturbed ground was left exposed to the constant prairie wind. Weather fronts lifted soil from Montana to Texas. As more farmers abandoned their farms, more soil was left exposed, and more dust blew, until the storms reached New York City and beyond.

By the late 1930s, the Roosevelt administration was working closing with farming communities to improve soil management practices. Then the rains began to fall again, and the tractors and plows returned.

Until the 1950s when it all began again.  More for another post.

If you have ever experienced a haboob or dust storm, please tell us about it in the Comments section below.


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