Wild Everest: over the top!

It's the ultimate natural wonder of the world. The rugged mountain peak of rock and ice is the planet's highest point of ground where earth and sky collide. Winds whip at 161 kilometers (100 miles) per hour; windchills plunge to 96 degrees Celsius (140 [degrees] F) below zero. But for thrill-driven mountain climbers, reaching the summit of wild Mount Everest is adventure's grand prize, the ultimate dream.

Almost six miles high, Mount Everest soars 8,848 meters (29,028 ft) above sea level--the tallest mountain on Earth in the world's highest and wildest mountain range, the Himalayas, which form the border between China and Nepal.

Climbers who dare to take on Everest face a rash of dangers: frostbite from severe cold, sunburn from glaring sun, snowblindness from the sun's blaze reflected off ice. Breathing the frigid air can cause such violent coughing that ribs crack like dry sticks. Add to that Everest's constant peril--shifting ice, deep chasms, brutal storms--and the prize seems hardly worth the murderous risk.

Yet since the first recorded European expedition in the early 1920s, nearly 600 mountaineers have made it to the top. Still, for every 30 people who seek to scale Everest, one dies. About 150 climbers have lost their lives on the mountain.

A CLIMBER'S GOAL

This spring, mountain climber Tom Whittaker hopes to join the rank of victors. If his dream comes true, he'll be the first disabled climber to reach Everest's summit.

After a car accident in 1979, doctors amputated, or cut off, Whittaker's right foot. But that didn't shatter his goal to become a world-class mountain climber. Born in Wales, Whittaker, 48, now trains future professional mountain guides in Prescott, Arizona.

With the help of a prosthesis, an artificial device replacing his missing foot, Whittaker continued scaling mountains after his accident. But what would inspire him to tackle the world's most daring climb? "Why does anyone run a marathon or play football? It's pitting yourself against something that is big--and you don't know if you can do it," Whittaker told SW.

In 1989, Whittaker reached 7,300 m (24,000 ft) high up Everest but was forced back to Base Camp after a violent storm blew in. In 1995, he tried again--this time mounting Everest's North Face up to 8,382 m (27,500 ft). But his body caved to the rigors of climbing at dizzying altitudes, and he became too ill to continue. This will be Whittaker's third attempt to wrestle Everest.

BREATHING LESSONS

How does Everest take its terrible toll on the human body? "Very few people can stay indefinitely at altitudes above 5,500 m (18,000 ft), and thrive," says Robert Schoene, a high-altitude physiologist at the University of Washington. The main obstacle: the amount of oxygen available for breathing. Oxygen is the gas nearly all organisms depend on to survive. Living things use oxygen to metabolize, or burn food for fuel and energy.

Whether at sea level, where most people live, or at Everest's peak, Earth's air contains 21 percent oxygen. But at such lofty altitudes as Everest's, less oxygen enters the lungs with every breath.

The amount of oxygen usable for breathing is determined by atmospheric pressure--pressure caused by air's weight. The greater the atmospheric pressure, the more closely oxygen molecules are jammed together. At sea level, where air weighs down heavily, living things inhale oxygen-rich air. But at higher altitudes, atmospheric pressure decreases, and air molecules are more spread out. Result: There's less available oxygen for a climber to inhale.

As a result, a mountaineer can easily suffer from hypoxia--lack of oxygen. To compensate, the body initiates a series of "struggle responses." First, a climber will begin to breathe harder, or hyperventilate, as lungs try to draw in more oxygen. Hyperventilating makes the heart beat faster and pump more blood per beat. (Blood carries oxygen to different parts of the body.) The bone marrow--the body's blood factory--also produces more new blood cells to circulate oxygen in the body.

All these responses protect the body from hypoxia, but only to a point. Sometimes the bone marrow produces so many blood cells that a person's blood becomes as thick as motor oil, Schoene explains. Then blood can't flow properly or deliver the body's oxygen efficiently.

MOUNTAIN SICKNESS 

In about 25 percent of climbers, the oxygen deficit results in acute mountain sickness (AMS). As the body strives to circulate more blood and oxygen to the brain, the extra blood can cause the brain to swell, leading to headaches, nausea, weakness, and shortness of breath. Drinking plenty of water and getting rest can relieve AMS.

But far more serious forms of mountain sickness attack climbers at altitudes above 3,660 m (12,000 ft). High-Altitude Cerebral Edema (HACE) occurs when the brain swells severely. The sufferer has trouble walking or using his hands, and may start to hallucinate. When fluids accumulate in the lungs, High-Altitude Pulmonary Edema (HAPE) can, in effect, drown a person. Both HACE and HAPE may result in death.

Interestingly, Sherpas (pronounced SHUR-puhs), native Himalayans who often guide climbers up Everest, rarely suffer from altitude-caused illness. Some scientists suggest the natives carry a gene--chemical instructions passed from parents to offspring--that lets them use oxygen more efficiently.

What are the best strategies for climbers like Whittaker to avoid altitude sickness? He should climb slowly so his body can adjust to the increasing altitude. Experts also recommend that mountaineers ascend no more than 300 to 400 m (1,000 to 2,000 ft) a day. Bottled oxygen also helps, especially above 7,300 m (24,000 ft).

Most important, says Schoene, the best way to tackle Everest is to practice scaling high mountains for 10 to 15 years. "People who climb 4,300-m (14,000-ft) peaks or hike up the Rockies have no real experience how to survive the brutal weather or high altitudes of the Himalayas."

What does Whittaker think of so many obstacles? "They're not as tough as getting through grade school," he jokes. But he admits this is the last time he'll try to tackle Everest's summit. "Most normal people would have said twice is enough. But somebody told me three is a charm, so I'm going back to try it one more time."

RELATED ARTICLE: Everest Highlights

mid-1800s

A survey of India and the Himalayas identifies the world's tallest mountain and names it after India's former chief surveyor, George Everest.

1953

On May 29 at 11:30 a.m., Edmund Hillary of New Zealand and Sherpa Tenzing Norgay become the first people to reach Everest's summit.

1954

The Indian government sets Everest's official height at 8,848 m (29,028 ft).

1957

Junko Tabei becomes the first woman to reach Everest's summit.

1978

Italian Reinhold Messner successfully scales Everest using no supplementary oxygen.

1996

Fifteen climbers die on Everest--the most deaths in any year. Many blame the increase in commercial expeditions--anyone who can afford the steep fee can climb.

RELATED ARTICLE: Tackling Everest!

What's the easiest way to reach Everest's summit? Most climbers prefer the South Col route, pioneered by Sir Edmund Hillary in 1953. They pitch camps at or near the same sites that have been used for more than 40 years.

BASE CAMP (5,334 m/17,500 ft)

Base Camp, complete with cooking and dining tents, is home base for climbers. It's also the storage center for food and equipment for climbing expeditions. The camp itself is higher than most mountains. Before reaching this point, climbers have already spent about a month at lower altitudes acclimatizing, or getting used to lower air pressure.

Khumbu Icefall

The most dangerous part of the climb, the Khumbu Icefall is actually a glacier--a large, moving mass of ice--filled with deep chasms and gigantic ice blocks.

CAMP I (5,944 m/19,500 ft)

This camp normally serves as a way station for climbing gear. At this altitude and above, humans can't fully acclimatize, no matter how long they stay.

CAMP II (6,553 m/21,500 ft)

Climbers spend a lot of time here to rest. At this altitude the body doesn't absorb much food--muscle cells become smaller and a person's strength decreases. Normally the body burns fat for energy, but at this height the body starts to burn protein as well. Burning protein, an inefficient source of energy, decreases climbers' strength.

CAMP III (7,163 m/23,500 ft)

A rest station for climbers, but only for a short period. After this point, most climbers use bottled oxygen to help them breathe while climbing.

CAMP IV (7,925 m/26,000 ft)

Nicknamed the Death Zone, at this level climbers' mental abilities, especially judgment, often become impaired. Lack of oxygen causes climbers to lose interest in eating or drinking. Falling asleep is difficult and sleep is not restful. The shorter climbers remain at this altitude, the better.

SUMMIT (8,848 m/29,028 ft)

At this extreme height, the body's physical abilities diminish at an alarming rate. Climbers can perform 1/5 the amount of work they do at sea level. And they use 50 percent of their work capacity just to breathe. (At sea level, breathing takes only 8 percent of the body's work capacity.)

RELATED ARTICLE: Everest Q & A

Everything you need to know--in case you ever go for a climb!

Q When and how did Mount Everest form?

A Everest and the Himalayas formed about 50 million years ago when two tectonic plates--large slabs of rocky crust--smashed into each other. The collision itself happened very slowly, but the results were as dramatic as two high-speed trains that crash head-on. When the Indian plate--moving at only about 10 cm (4 in.) a year--rammed into the slower-moving Eurasian plate, it thrust up the Eurasian crust like a snowplow amassing mounds of snow. Result: the highest mountain range on Earth. The Himalayas continue to grow--rising a few millimeters each year as the Indian plate slowly plows into Eurasia.

Q Just how high is the world's tallest mountain?

A The truth? Scientists don't know for sure. Officially, surveyors in 1954 measured Everest to be 8,848 m (29,028 ft) high. But the layers of snow and ice on the mountain's summit make it almost impossible to map the actual rocky peak. Also, at the Himalayas, scientists are having a hard time calculating sea level--the level from which mountain heights are measured. They think the gravitational attraction of the huge mountain range draws water up. Until they can accurately calculate how high the water bulges, scientists won't know Everest's height for sure. But they are positive that Everest stands taller than any other mountain in the world.

Q What's the weather like on Everest?

A No day at the beach. In the summer, heavy rains (and snow at higher altitudes) pound the mountain. At times, gale-force winds, described by climbers as a deafening roar, whip endlessly. In the winter, jet streams--masses of fast-moving air 10 to 14 km (6 to 9 mi) above the Earth's surface--roil over the mountain and even descend on Everest. Then "the winds on the summit can go from 25 to 150 knots (29 to 173 mph) instantly," says meteorologist Bob Rice. Such ferocious winds have literally blown away climbers. To predict weather on Everest accurately, scientists installed a weather station near its peak in 1996.

Q Is it always freezing on Everest?

A Because of its high elevation, temperatures are generally frigid on Everest. But in some places, like the Western Cwm (pronounced koom) at 6,400 m (21,000 ft), snow reflects the sun's light and heat so intensely that climbers feel like they're hiking inside an oven. Even though air temperature may be below freezing, the sun's reflected rays often force mountaineers to take off outer clothing layers to keep cool.

Q Who "takes out the trash" (oxygen bottles, tents, etc.) that climbers lug up with them?

A Unfortunately, the world's highest mountain is also its highest junkyard. Climbers haul tons of food and equipment, plus oxygen bottles, to the top. Most of it becomes litter and debris. Since 1994, climbing expeditions have made a concerted effort to clean up Everest. In addition to picking up after themselves, climbers are hiring Sherpas (Himalayan natives and Everest guides) to bring down used oxygen bottles; they make up the bulk of garbage. Mountaineers then ship the bottles back to their countries of origin for recycling.