Saltation Gives You That Epic Feeling: Will Dust Storms Return?

I’ll never forget my first haboob. I was playing alone in the shade on my front porch when the blazing, still, summer afternoon suddenly changed. I noticed the difference in air pressure first, but it was strange. The feeling resembled the tingle and gathering tension before a thunderstorm, but the sky was perfectly clear as far as I could see – and on a clear day, I could see for twenty miles north and east from the front porch of my little house in the foothills. Of course, half my view was blocked by the house itself, so I crossed the porch to look west–

Then it hit me. Before I even saw the towering wall of dust rushing toward my home from the valley below, a gust of wind picked me up and threw me almost twenty feet away. I landed flat on my back and just lay there in a breathless daze as the first prickling trails of hot dust swirled over me like the antithesis of snow. Then I rolled over and crawled up the porch steps to my front door because I couldn’t get back on my feet; at the time, I wondered if I would be buried alive.

I watched the rest of the dust storm from my northwest-facing bedroom window, and haboobs have been my favorite type of weather event ever since.

It’s been years since I left the desert, and years longer since I’ve been swept off my feet or stranded in a car on the roadside by a miles-wide swath of sand and topsoil churning across the sky. It’s the sort of event that myths and legends are made of. You can imagine my pleasure at discovering how well-documented the big haboob was in Arizona on July 5th. There was footage from so many different angles that I built a YouTube dust storm playlist so I could enjoy that epic feeling anytime I want.

Nowadays, the internet (among other infrastructure privileges) allows us to enjoy events of mythological proportions from a safe distance, but just a lifetime ago, in the 1930s, a plague of dust storms blew away as much as 75% of the usable topsoil in many areas of the American Great Plains. History calls that period the Dust Bowl, and it made the Great Depression even worse. Bad agricultural practices and bad timing combined to create such potent misfortune that about 2.5 million people abandoned the Great Plains states altogether.

And it could happen again. Just as the current economic situation is hauntingly familiar, so do the agricultural practices of the twenty-first century still closely resemble the erosion-enabling farming of the past. Add to those factors the history-repeating drought the southern United States already have their fill of, and we’re going the right way for a perfect haboob. Maybe even another plague of dust storms.

Speaking of plagues, it’s worth noting that these gorgeous, devastating weather events lift a lot more than just grit into the air. The grit is bad enough on its own – it can blind you, and inhaling it can cause Silicosis and even death – but along with the dust, these storms toss all sorts of microbes high into the atmosphere. Given an epic boost like that, even tiny germs can travel the world.

All of which is very interesting, and scary, but doesn’t really explain the storm. For years after my first haboob, I wondered what caused the dust to rise so high and how it stayed aloft so long. To my fascinated mind, the ‘I dunno’ chorus from family and teachers became a vast, weather-less landscape of ennui. I eventually dredged an answer from a dusty tome in some neglected library, but thanks to the internet, you can have it today.

It sounds like a greeting, but the process by which pebbles creep, sand leaps, and ordinary dirt can fly for miles is called saltation. The recipe is simple: Given sudden high wind and loose dry soil, aerodynamics will combine with a little static electricity, and voila! You get saltation. On a large enough scale, simple saltation can turn a clear day pitch black in a matter of minutes, and turn boom towns into ghost towns practically overnight. Is it any wonder the process still sweeps me off my feet?

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