Zoom: From Atoms and Galaxies to Blizzards and Bees: How Everything Moves (15 page)

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Authors: Bob Berman

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BOOK: Zoom: From Atoms and Galaxies to Blizzards and Bees: How Everything Moves
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I arranged interviews with Mount Washington’s scientists, who live for eight days at a stretch in the observatory atop the summit. I was seeking specific information, fishing for an exact blown-off-the-mountain wind speed, the kind of juicy stat that conveys a dramatic image. But with the cautiousness of a good meteorologist, Dr. Brian Clark wouldn’t give me one.

“There is no threshold wind velocity that will reliably knock people down. It depends on a person’s height and build,” he explained.

“Well, what wind speed will blow you over?” I asked.

“It depends. It’s much harder to stay standing when it’s very gusty as opposed to a steady wind that you can lean into.”

“How gusty?”

“It depends.”

I wasn’t getting anywhere. I tried a different ploy.

“Listen, your own media relations person, Cara Rudio, already told me that most people are knocked off their feet when gusts hit the high eighties or low nineties. Would you agree with her?”

“She said that?”

“Yes.”

This gave Clark some pause. He then insisted that experienced professionals, who venture out each hour to clean ice off instruments and take readings, often remain on their feet even above one hundred miles per hour. After all, he explained, the entire staff undergoes “slide and glide” training.

“Well,” he finally and grudgingly conceded, “I guess no one could remain upright at one hundred and fifty miles per hour.”

Why is this place so windy? It seems Mount Washington sits at a perfect storm location at the convergence of three major storm tracks, plus its prominence within the surrounding landscape amplifies the winds, plus there’s a funnel effect, like the venturi of a carburetor. In terms of the world’s highest-ever gust observed by people (as opposed to unmanned instruments), Mount Washington still holds the record: 231 miles per hour, recorded in April of 1934.

After Evangelista Torricelli proved that air moves in response to differences in pressure and temperature, there still remained the small matter of what, exactly, air is. This required more than a full additional century of labor. The knowledge arrived via a flurry of discoveries just before the American Revolution.

Turns out air is a simple mixture of around 78 percent nitrogen and 21 percent oxygen. Everything else is an afterthought—less than 1 percent combined. And of that remaining 1 percent, argon—the inert gas inside every lightbulb—constitutes 0.93 percent. Nitrogen, oxygen, and, okay, let’s include argon. The big three. Now you’ve identified 99.93 percent of the atmosphere. (When it’s dry, that is. The presence of water vapor varies so much from place to place that it’s usually omitted in this kind of conversation.)

After argon, you’re down to tiny fractions of eolian ingredients, such as carbon dioxide, a mere twenty-fifth of 1 percent. It’s scarcely present at all, despite its greenhouse notoriety. Yet it was discovered before the other gases.

That’s because CO2 is readily emitted in all sorts of chemical reactions, such as the one that happens if you throw some baking soda into vinegar. It’s easy to produce, hence it was easy to discover. Air’s two major components were a bit trickier yet were isolated almost simultaneously. Nitrogen was identified in 1772, oxygen in 1774. Their main distinction was immediately obvious. One supported life and combustion, the other didn’t.

The big nonoxygen player soon acquired a ghoulish reputation. Nitrogen’s discoverer, Daniel Rutherford, called it noxious air. Other chemists alluded to it as burnt air. The French “father of modern chemistry,” Antoine Lavoisier, called it azote, from the Greek azotos, meaning “lifeless.” Mice placed in it quickly died. But officially designating the bulk of Earth’s atmosphere lifeless would have been kind of creepy. Fully eighteen years after its discovery, the current name was suggested.

As for oxygen, this was the precious, life-sustaining element everyone was then trying to isolate. Because—unlike the “introverted” nitrogen—it eagerly combines with most other elements, it makes up two-thirds of our bodies by weight. By itself it accounts for half the mass of the moon. When coyotes react to the lunar crescent, it is basically a display of oxygen howling at oxygen.

CHAPTER 9: Blown Away

A Fanatical Mariner Takes the World to the Edge of Violence

Will the wind ever remember

The names it has blown in the past…

—JIMI HENDRIX, “THE WIND CRIES MARY” (1967)

In the same year the mostly-made-of-oxygen Joseph Priestley discovered oxygen, Francis Beaufort was born in Ireland. Thus we now finally arrive at the modern study of airy motion to which his name was attached for centuries, thanks to the famous Beaufort scale.

For it is one thing to finally know why the wind blows and what it is. It is quite another to watch houses carried off, as in The Wizard of Oz. Why on earth should moving air ever accelerate from a sixty-mile-an-hour gale that merely rips branches off trees to a two-hundred-mile-an-hour fury that kills dozens at a time?

Classical and Renaissance scientists had obsessed over air and triumphed. But it took until the nineteenth century for a new breed of scientist to emerge, one whose fascinations revolved around violence.

When the year 1971 began, the world had no system for measuring or even speaking about the most savage winds. The Beaufort scale, which we will explore in a moment, had been used for 166 years but only goes up to “hurricane.” Once your roof blew off you were on your own to shout out any further wind-defining expletives you wished to add.

In reality, hurricanes are no more alike than are earthquakes: that single word can mean everything from an unfelt tremor to a violence that literally tosses animals in the air and abruptly kills a half million people. Some hurricanes let intrepid reporters deliver televised accounts safely from the boardwalk; others can blow that same meteorologist to the ground.

So Bob Simpson, director of the National Hurricane Center, teamed up with civil engineer Herbert Saffir, an expert on designing buildings with high wind resistance, to create the Saffir-Simpson scale, which rates the strength of hurricanes. Back in 1971, when minimalism was in fashion, their categories ran from a simple one to five.1

Because tornadoes are different kettles of fish, Ted Fujita, originally a professor in Japan before coming to the University of Chicago in 1953, created a scale just for them—also in 1971. The original Fujita scale had thirteen levels, F0 through F12, the highest levels of which were purely theoretical—imaginary winds raging at the speed of sound.

But he had created too many categories. Fujita saw the light and chopped the number of varieties down to six. These days the scale, which was further tweaked and renamed the Enhanced Fujita Scale, also takes into consideration the degree of expected damage. The weakest tornadoes are thus EF0 and EF1; the strongest is EF5.

Of even greater importance, Ted Fujita, who died in 1998 at the age of seventy-eight, also discovered the microbursts and downbursts that destructively tumble from the bottom of thunderstorms. These may actually be more interesting phenomena than tornadoes, simply because most of us occasionally encounter them firsthand.

Thunderstorms are wind machines. Here is animated air motion made darkly visible. They’re even easy to understand. You don’t have to be a Galileo to figure out what’s happening. You start with a hot summer day, the sun heating the ground, which warms the air just above it. Warm air rises, so up goes a gas bubble like a hot-air balloon. This is called convection. It’s invisible, although planes flying through such rising air get very distinct bumps of turbulence.

As we’ve seen, temperature normally falls rapidly with altitude. So a rising surface-heated air glob is warmer and thus lighter than the surrounding cool air and thus keeps ascending until it cools to achieve equilibrium with its surroundings. But if the day is humid, the rising air package remains much “lighter” than the air around it, so it keeps going up, sometimes to near-stratospheric heights. Eventually it cools to its dew point and can no longer hold its moisture, which suddenly condenses into countless billions of teensy droplets. A cloud is born.2

Wind normally increases with altitude. At the 20,000-foot summit of Mount McKinley, left rear, winds howled at forty-five miles per hour, a common value, blowing snow and creating a standing wave lenticular cloud near the author’s chartered plane, in 2014. (Anjali Bermain)

Hot air from below keeps rising to feed this cloud. It pushes sections of the cloud higher, forming a menacing cauliflower shape that can top forty-five thousand feet, beyond what any airliner can reach. Meanwhile its droplets rub together to create static electricity. At the same time, since you can’t have a vacuum on the ground below, surrounding air is pulled in. The air pageant is now getting more and more animated. When rain starts forming and falling, cooling the air within the cloud, this denser cold air plummets, intertwined with the rain.

Now you have scary-strong winds. Some warm air is still rising into this “mature” thunderstorm while adjacent streams of cool air are plunging down from it. Even in a moderate storm the downdrafts register twenty-two miles per hour to match the speed of the surrounding downpour. If you’re in a small plane you suddenly find yourself pushed earthward like a giant metal raindrop. You aim your nose upward and add all the power you can and hope you can outclimb it.

The downdraft, which can be a half mile wide, now hits the ground and, unlike the liquid rain, spreads radially outward in all directions, bending trees horizontally and inverting umbrellas. The violence contains complex turbulence because nearby updrafts can rise at this same speed. Now your plane, having successfully passed through the downdraft, encounters an adjacent column of fast-rising air. Suddenly you’re sucked up toward the angry black cloud above. You push forward on the yoke, pointing your nose down. In many documented cases, the pilot wasn’t able to dive fast enough to counterbalance the wildly rising air, and the plane was pulled into the roiling cloud as if by a conscious, malevolent monster.

No wonder all aircraft give thunderstorms a wide berth. Once, near Hartford, Connecticut, I experienced a frightening rapid downdraft when flying in clear skies, fifteen miles from where a storm had passed a half hour earlier. The air was still plunging violently.3

Such intensity turns up the juices, but real “fun with wind” lies in everyday life. Sure, it’s cool to have some background, to know that temperature differences give birth to air motion. And that the shape of the terrain—for example, a narrow valley that’s aligned with wind direction—can funnel it to faster speeds. Still, the act of simply observing the wind as it momentarily alters the world can provide immense enjoyment.

Everything depends on speed. Most nature-challenged people think in broad terms of a day as being “not windy” or “windy” or “very windy.” What Beaufort brought to the table was a way of precisely translating wind’s speed to what it does.

Francis Beaufort (1774–1857) had been shipwrecked as a teenager because of a poor navigational chart and consequently developed a lifelong obsession with making the seas safer through better maps and better understanding of the wind.

He started his seagoing career on a merchant ship belonging to the East India Company, then he joined the Royal Navy and worked his way up from the rank of midshipman to the rank of lieutenant during the Napoleonic Wars. He became a commander at the age of twenty-six.

He was badly injured in duty twice, but it never made him gun-shy or ocean-wary. His steadiness earned him growing admiration. He impressed everyone with his dedication, attention to detail, and scrupulous notes about sea conditions. He was the archetypical meticulous British commander, an inspiration for one of the characters in Gilbert and Sullivan’s H.M.S. Pinafore: “I am the very model of a modern Major-General.”

He became a captain in the Royal Navy in 1810 and spent his leisure time measuring shorelines and making improvements to charts. His reputation for intelligence, leadership, scientific integrity, and energetic devotion steadily grew and spread through the naval bureaucracy until even members of the nobility knew his name.

He accepted invitations to join the Royal Society and the Royal Observatory, helped found the Royal Geographical Society, and met all the great scientists of his day. As a top administrator, he helped coordinate the work of Britain’s geographers, astronomers, oceanographers, and mapmakers and arranged funding for scientific expeditions. Beaufort trained Admiral Robert FitzRoy, who was appointed to command the survey ship HMS Beagle for what would become her famous second voyage. He recommended that “a well-educated and scientific gentleman” named Charles Darwin be invited as the captain’s companion. As we all know, Darwin used this voyage’s discoveries to create his theory of evolution, presented in his book On the Origin of Species.

So Beaufort was no mere hobbyist with a home-built anemometer. In 1805 he drew on his own wind observations and those of others, especially Daniel Defoe, who later became famous for his novel Robinson Crusoe, to create the air-motion scale that has borne his name ever since.

(Mark Twain said, “Everyone is a moon, and has a dark side that he never shows to anyone.” It didn’t seem as if Franicis Beaufort had any unseen sides to his celebrated meticulous personality. But after his death in 1857, his private letters were assembled, and many were found to be written in a personal code of his own design. It was a good code for its time, but it was readily deciphered by experts and found to reveal numerous confidences about personal problems, conflicts with colleagues, and secrets of a sexual nature. The moral might be: shred your documents if you don’t want your secrets published posthumously.)

By the late 1830s, the Beaufort scale was made standard for ship’s log entries on Royal Navy vessels. By the 1850s, others had adapted it to correspond with anemometer readings so it could be used on land. Then in 1916, as steam power made sailing ships obsolete, Beaufort’s descriptions were changed so that they described how the ocean, not the sails, behaved. Further additions improved the scale’s validity for land-based observations.

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