Monday, April 4, 2016

Dust devils, dust storms, and haboobs, oh my

By Camille St. Onge, communications

Eastern Washington’s nutrient-rich soil is perfect for agriculture, but it’s also a perfect starting place for dust storms, ranging from simple dust devils up to massive haboobs.

Much of Eastern Washington is blanketed with a fine-grained soil called “loess.” It’s mainly found in the Columbia Plateau and Palouse region of Southeastern Washington. Loess is rich in organic nutrients and vital for agriculture such as wheat farming. It also sets up conditions nicely for dust storms in the region. 

Is it comparable to Dust Bowl of the 1930s — a terrible natural disasters in U.S. history? Not really. But, with more droughts and extreme weather projected because of our changing climate we’re likely to see more of these gnarly dust storms in the future here in Washington. 

Let's break it down

If you live in Western Washington you may be asking yourself, what dust storms?

On the west side, the warm winds kick up an occasional dust devil - strong, well-formed whirlwinds. A dust devil can range from 30 feet to as much as a 3,300 feet tall, but few in the west part of the
Dust devil
state last long enough to cause real problems.

East of the Cascades, blowing dust is a much different story because the geological makeup of the region is very different.

Eastern Washington’s soil is a legacy of the flooding and erosion caused by retreating glaciers at the end of the last ice age about 10,000 years ago. These massive floods left behind the characteristic “channeled scablands” of dramatic buttes and mesas.

As the Earth’s climate became warmer, these channeled scablands dried and soil began to blow away. Over time, the soil has been constantly blown and redeposited, producing the landscape we see in Eastern Washington today.

Today, a strong gust of wind can easily sweep up the soil and can carry it for miles.

And then there’s the dreaded haboob.

According to Clint Bowman, atmospheric scientist with the Department of Ecology, haboobs are like a dust storm on steroids.  

Haboobs occur when a thunderstorm creates a strong downdraft of cold air, which slams into the ground and spreads out like a pail full of water hitting a concrete walk. The effect produces strong winds right at ground level, where they scour the soil and can build into a devastating wall of dust and dirt.

In 2014 and 2015, haboobs in Eastern Washington brought visibility to zero, knocked out power, caused several car accidents, and forced officials to close highways as it moved through multiple Washington counties before dissipating over the Idaho Panhandle.

Dust Storms - Haboobs

Dust can be gross

Dust can be made up of pollen, bacteria, smoke, ash, salt crystals from the ocean, and small bits of dirt, rock, or sand. It may also contain tiny fragments of human and animal skin cells, agricultural chemicals, and hair. Take a moment and think about breathing that in.

One of Ecology’s roles is to warn about air pollution issues that could affect people’s health.

Infants, small children, asthmatics and people with other respiratory and cardiovascular diseases are affected more than the general public, and prolonged exposure to blowing dust can lead to serious respiratory problems for these groups.

The National Weather Service looks for potential visibility issues that could create hazardous driving conditions. The limited visibility during major dust storms sometimes leads to severe car accidents.

Because of our mutual interest in warning communities of these hazards, the National Weather Service and Ecology work together to get the word out through “blowing dust advisories.”

Local television and radio stations share the warnings, and both agencies use social media to spread the word. 

Dust bowl no more!

Did you know that the Soil Conservation Service was formed during the Great Depression to address the soil erosion that caused the Dust Bowl? This agency was the forerunner to the USDA's Natural Resource Conservation Service. The NRCS and local conservation districts assist growers to implement soil erosion conservation measures today.

Fortunately, the Washington agriculture industry actively uses erosion control practices and works in partnership with Washington State University’s College of Agriculture to employ best practices to minimize erosion. WSU has developed farming practices that allow growers to control wind erosion and dust emissions, and to assist them with adopting these practices on their farms.

Ecology does its part by monitoring dust storms and working closely with the U.S. Environmental Protection Agency to ensure it is aware when dust storms cause air pollution levels to exceed federal air quality standards. 

Melbourne, Australia

Dust storms in Washington and around the world

While dust storms in Washington can cause health and driving risks, our state does not face the extreme dust issues facing other dry and arid states and countries do. The 1983 Australian dust storm that covered the city of Melbourne was a famous example of the power of these storms: The deserts of Australia were experiencing drought, so sand and soil were loose. The dry conditions set up about 50,000 tons of material to erode as dust. A strong cold front brought winds that swept up that dust and, over the course of a single afternoon, choked Melbourne under an estimated 1,000 tons of dust. It took years of work and millions of dollars to repair the damage caused by the storm.

Check out dust devils, dust storms, and haboobs from around Washington and the world by exploring the links below. For more information about blowing dust in Washington visit our outdoor dust page

Dust devils, dust storms, and haboobs:

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