Nadav Ben Yehuda's right hand can't grasp a pencil. No longer can he sit on the side of a mountain scrawling poetry in his climbing notebook. The nerve damage causes him to drop things without warning.

But Ben Yehuda still has his life, which wasn't a certainty as he lay on his back on the Nepal side of Mount Everest a year ago, cursing and looking for hope in a sliver of sky between the rocks and clouds.

In 2012, the 24-year-old set out to become the youngest Israeli to summit Mount Everest, with five years of ice climbing and three years of Israel Defense Forces training under his belt.

Yet none of his training prepared him for the crowds he encountered at Everest base camp 18,000 feet above sea level. Ben Yehuda often climbed alone and welcomed run-ins with other adventurous souls, but there he found hundreds of people at the base of the world's highest peak.

"It was like looking at the Woodstock festival," he said. "I saw all of those tents and I thought, 'Is it possible that all of the ice climbers in the world are here?'"

Nadav Ben Yehuda. Nadav Ben Yehuda

With 10 deaths last year, the third-deadliest Everest climbing season on record, questions are being raised about the safety of granting government permits to so many climbers, many not versed in the perils of living miles above sea level.

Until the late 1970s, only a handful of climbers reached the top each year. The number topped 100 for the first time in 1993. By 2004, it was more than 300. Last year? More than 500.

The deadliest year was 1996, when 15 people died. Eight of them succumbed during a blizzard so violent that journalist Jon Krakaeur chronicled the tragedies in his bestseller " Into Thin Air ." Another 12 climbers were killed in 2006. This year there have been media reports of eight deaths, as of May 23.

The mountain represents both choice and risk: Are you ready to push life to the edge to reach the top of the world? Or does life matter more?

Hoping for the summit

At base camp in April 2012, Ben Yehuda watched climbers learning to don shiny new crampons -- metal traction aids strapped to boots soles. Some put them on backwards. Others were familiarizing themselves with the horizontal ladders used to cross dangerous ice crevasses

Ben Yehuda was immediately worried.

Meanwhile, American geographer Jon Kedrowski , 33, was looking for his elite expedition team, which included Canadian Sandra LeDuc , 34, who was climbing for charity. Team leader Arnold Coster told him their tent was by the helicopter pad. Kedrowski counted at least 40 tents and 30 teams.

Nepali-Canadian Shriya Shah Klorfine , 33, was bolstering her experience by climbing peaks near base camp. Ascending Everest was her dream, one that worried her husband, Bruce. He didn't think she had enough experience. A Sherpa watching her climb concurred.

Shriya during a practice climb, before attempting Everest. Courtesy Bruce Klorfine

The climbers arrive in April to acclimate to the altitude before heading toward the summit. Between May 15 and 30 is usually the best window. There are typically 11 days in spring when people can stand on the summit, according to meteorologist Chris Tomer , Kedrowski's best friend.

This wasn't the case in 2012, with bad weather cutting the window to four days. A monsoon would move in afterward. The dry year in the Himalayas brought added dangers of shedding glaciers and unstable rock.

Forecasts pegged the first window at May 19. Teams assembled their gear at base camp. Groups, including International Mountain Guides, went team to team asking when climbers were leaving for the first succession camp. It was estimated 150 to 250 people would be climbing simultaneously.

Because steep vertical ice walls and tricky passages require a single-file ascension, IMG and others warned against so many people climbing at once. Few listened.

Back in Denver, Tomer was worried. He warned Kedrowski that winds might pick up earlier than anticipated, slamming the summit window shut and stranding climbers.

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Everest pierces the jet stream, the flow of air that carries airplanes, and the sustained 100-mph winds make summiting outside of May nearly impossible. In May, the winds coming off the Indian Ocean lighten, lifting the jet stream above the summit by 10 to 15 feet, enough to stand on top of the world, Tomer explained.

Kedrowski and LeDuc decided to wait a day so the crowd could move ahead. They might still be able to summit May 20, they thought. Klorfine and Ben Yehuda, however, began their separate ascents.

Disaster in the death zone

Before the summit at 29,028 feet, climbers must traverse the aptly named "death zone" at 26,000 feet. There are more than 200 bodies in the area, although it's presumed you can't see them beneath the ice.

Climbers need bottled oxygen to breathe. Frostbite and extreme altitude sickness are real dangers. Unrelenting winds can make a 1-mile trek hours long.

Above this lies the Hillary Step, named for Sir Edmund Hillary, the first man to conquer Everest, along with Tenzing Norgay. It's a nearly vertical rock face stretching 40 feet to the summit. Because climbers can't pass each other, a logjam extended from Hillary Step to the death zone.

As nearly 300 people vied for the summit on May 18 and 19, the worst imaginable scenario came true.

People with varying degrees of experience labored up the face as the weather shifted. Exhausted from so little rest in the four succession camps, they were also short on oxygen and losing weight because the thin air makes it tough to metabolize food.

They waited for hours in the death zone, their chances for survival shorter by the minute. Some had to summit as evening fell, something no seasoned climber would attempt, Kedrowski said.

Then the storm arrived.

Visibility dropped. The climbers crept. They ran out of oxygen, their estimates shot after waiting so long in the death zone. Sixty-mph winds leeched their body heat. Down-filled suits, thick boots, layered gloves, hats and goggles couldn't beat back a wind chill of 70 below, Tomer said.

For some teams, survival trumped summit as the ultimate goal. Others had altitude sickness, but after flying to Nepal and paying thousands of dollars, they felt had to reach the top. Hypoxia, the deprivation of oxygen, made their own decision-making an obstacle.

Klorfine eventually reached the summit, but her journey home would end in the death zone, along with three other climbers from Germany, South Korea and China.

Love and determination

Klorfine was bright and intense, a passionate idealist. The same qualities that compelled her to summit Everest also spoke to Bruce Klorfine's heart in July 2001, when the two met though their work on a cruise line between Boston and Bermuda, he said.

Shriya and Bruce Klorfine. Courtesy Bruce Klorfine

Bruce was the piano player in a lounge, Shriya the lounge hostess. From the beginning, their relationship was fun and romantic, paradise its backdrop.

"She made me rise to a certain level of intensity because I felt she had that, and I rode the wave," Bruce said. "It was easy to imagine starting a life with her."

Bruce bought a ring in 2002, while they were docked in the Caribbean. He proposed on the ship. In April, they were married in Mumbai, where she lived, before moving to Bruce's home in Toronto. She wanted to be an entrepreneur. She encouraged Bruce to turn his IT hobby into a career.

Originally from Nepal, Shriya often discussed Everest before revealing in 2011 that it was her dream to climb the legendary peak. It made Bruce nervous, but Shriya was serious, as she was with all her goals.

"To be honest, I'm still really struggling to understand why her, and why that endeavor," he said.

She was an independent soul, like him, and after realizing she wouldn't be swayed, he supported his wife's ambition.

They'd talk sporadically when Shriya reached base camp, mostly about everyday things, He didn't want to trouble her with his worries.

Her last call came while he was at work. He had no privacy so he couldn't tell Shriya he loved her. Instead, he told her to stay safe. Shriya said she wouldn't push herself too hard.

Like many of the climbers on May 18 and 19, she saw an opportunity and took it, but she climbed too slowly and used too much oxygen. Everest forgives neither.

Shriya on the Everest summit, holding the Canadian flag. Courtesy Bruce Klorfine

Bruce learned of her death the same way he learned of her summit, through a phone call. He flew to Nepal and paid to airlift her body down from the mountain. He'd learn of the persistence that killed her, how she wouldn't turn back and descended on her own with a single bottle of oxygen someone gave her.

"It was a flawed plan, but I really feel it highlights what was best about her in a way -- the determination to accomplish something that she set her heart on," he said. "I could never underestimate her. ... I feel like I understand it, even if people say it's foolhardy or thoughtless or stubborn. In a way, it's her finest moment, really."

A daring death zone rescue

Ben Yehuda had had a bad feeling the night before, and as he attempted to reach the summit, he was unable to pass the crowds. An experienced climber, he should've made it from Camp 3 to Camp 4, in the death zone, in six hours. It took almost 13.

Once there, Ben Yehuda opted to remain at Camp 4 to let the crowds pass. He sipped on his oxygen to conserve it, but his brief pit stop stretched into 24 hours.

When he resumed his climb, Ben Yehuda came across a body. He expected to see them in the death zone, but not in 2012 expedition gear.

It was Klorfine. He'd met her at base camp. Two hours later, he saw the body of Song Wondin. He touched each one to see if they were alive. Neither was wearing an oxygen mask. They were still attached to ropes. Every climber had to pass them.

"They were hugging themselves like a baby in a mother's belly, folded into themselves," Ben Yehuda said.

Ben Yehuda encountered another body in an ice crack 984 feet below the summit. The man had only one crampon on -- no gloves, no mask. His ice-white face was swollen with frostbite. He was wearing a familiar hat.

It was Aydin Irmak, a 46-year-old Turk Nadav knew from base camp. They had played cards. Nadav had warned Irmak in Camp 4 not to join the crowd cluttering Everest's face.

Again, Ben Yehuda touched the body. The man groaned. He was disoriented and unconscious, but alive -- a miracle considering his exposure in the death zone.

Ben Yehuda decided to forego his summit attempt. This man was not going to die. Ben Yehuda was going to get them down, and he knew it meant they both might die.

Ben Yehuda connected Irmak, a man roughly his own weight, to his rappelling harness and began to maneuver them down. Soon, Ben Yehuda's oxygen mask froze.

"It's like someone is taking a belt and putting it around your neck and pulling as hard as they can," Nadav said. "I thought we would become part of the mountain for sure."

An hour into the descent, Ben Yehuda removed the mitten covering two gloves on his right hand so he could hold Irmak and the rope more securely. Minutes later, his right hand froze in position, clenching the rope.

He cursed, over and over, suspecting he would lose his fingers.

They passed a Malaysian man, attached to the ropes by his harness, his chest rattling with the sound of a lung edema. He couldn't talk, couldn't move. He, too, was dying. Ben Yehuda asked a passing British climbing team to help him, to give the man oxygen. He learned later they did, and the Malaysian climber was able to rescue himself.

Ben Yehuda soon lost the ability to rappel. He needed the rope loose, but too many people were on it, making it tight. Irmak slipped from Ben Yehuda's grip. Both men slid down the ice.

Irmak fell into an ice crack, dragging Ben Yehuda with him. The rope tangled around Ben Yehuda's legs, threatening to bury him in the ice crack as well. He used ice axes to dig them out, but it took precious time.

Eight hours after finding Irmak, the two men reached Camp 4. Ben Yehuda was dragging Irmak by then, barely able to stand.

But it wasn't over. Rescue helicopters can't reach above Camp 2 because the air is too thin.

After resting for a few hours and examining his frozen right hand, now swollen to the size of a baseball glove, Ben Yehuda took another 20 hours to get Irmak to Camp 2.

Approximately 328 feet from the camp, Ben Yehuda fainted in the snow. Other climbers found him, fully hypothermic, and put him in a tent. Without food or a stove, he lived off ice for more than 28 hours.

The next morning, Ben Yehuda awoke to someone shaking his tent. It was Irmak, who couldn't speak from his frostbitten face, but he looked at Ben Yehuda and his deformed hand.

"It was a moment of happiness, of anger, of many things together," Ben Yehuda said.

The two men required extensive treatment once they were airlifted out of Camp 2. Back in Israel, Ben Yehuda was treated for brain damage, lung problems and his frostbitten face and legs. Some operations were canceled or delayed because he'd lost so much weight. It would take him months to regain the 42 pounds he lost on Everest.

Doctors wanted to remove every finger but the thumb on his right hand, but Ben Yehuda wouldn't allow it. He received orthopedic and plastic surgeries instead.

He's kept in touch with Irmak, who suffered a brain edema and doesn't remember much of the rescue. Ben Yehuda has shown him photos that spurred his memory. Klorfine's body can be seen in one of them.

The summit and the storm

Like Ben Yehuda, Jon Kedrowski and Sandra LeDuc waited for the crowd to thin out. They had prepared for years, and LeDuc wanted to tick Everest off her list of the "seven summits" -- the highest peak on each continent. Everest was No. 5.

Jon Kedrowski Courtesy Jon Kedrowski

Kedrowski had designs on a fast and light climb with a low flow of oxygen. Back in Denver, Tomer, the meteorologist, was blogging based on Kedrowski's texts, e-mails and satellite phone calls . LeDuc's brother was sending out tweets to her 60 followers.

One night, in Camp 2, they heard a boom emanating from Camp 3. An avalanche had descended on part of Camp 3, shredding the tents they had placed in advance. If Kedrowski and LeDuc had been in Camp 3, as planned, both would've been killed.

More trouble ensued when LeDuc's Sherpa was injured in a rock fall. He had to be airlifted off the mountain.

The next day, they saw people near the south summit. Kedrowski assumed they were summiting, that the weather window was holding. A day of climbing passed before he realized the climbers were beginning their descent.

At Camp 4, Kedrowski and LeDuc's team realized something was wrong. People were being carried into camp unconscious, their faces iced over. It was hard to tell who was alive.

"Is that normal?" they asked one another.

A storm moved in. The winds lashed the camp. Five or six lightning strikes flashed in the sky as visibility neared nil. Kedrowski and LeDuc couldn't see 3 feet in front of them. They began encountering dead and dying climbers, one of them Klorfine.

At one point, a 100-mph gust blew Kedrowski off his feet.

"My face felt like it was being sandblasted," he said.

They had no choice but to turn around, but LeDuc's regulator froze, cutting off her oxygen. Sherpas had to revive her.

Kedrowski soon encountered Song Wondin, the climber Ben Yehuda would find dead. His mitten was off. Kedroswki tried to hand it back to him. Wondin looked at him with frozen eyes -- icicles hanging from his beard -- swatted the mitten away and passed out.

Kedrowski tried to pick him up, but he was unwieldy, almost dead. He waited for other members of his team to descend, but it was too late.

Almost everyone on the team sustained an injury. One had a broken rib, another a frozen cornea. They were exhausted, traumatized. They sat in tents at Camp 2, reeling, shell-shocked, before returning to base camp.

Kedrowski and LeDuc were beat, but not beaten. They recovered in time for the season's last weather window, May 26, which was forecast to bring calm winds.

Climbing harder and faster than they'd ever climbed, they skipped camps 1 and 3, making the four-day trek in two. They stood atop Everest on the last possible day.

Kedrowski shed a few tears, and Sandra, who often found it difficult to relish her accomplishments, found a moment she could relive forever.

The summit itself is quick -- snap photos, pose with your flag, take in the panorama and descend -- but the memory endures forever. Still, their journey was only half over.

Sandra LeDuc on the summit, holding the Canadian flag. Sandra LeDuc

They had to find the energy to get back down after being awake for 38 hours. It wasn't until they reached base camp that relief set in. Kedrowski hugged LeDuc and said, "Now I know we're going to live."

"It was this amazing, surreal feeling, this energy coming from elsewhere," LeDuc said. "I like to think there were a lot of people home who were thinking of me and that support carried me."

A year later

A year has passed since their expeditions. Kedrowski and LeDuc still love climbing, but the experience has changed them.

LeDuc's 60 Twitter followers ballooned to thousands who wanted to follow her journey. Media reached out, asking her to elaborate on something she tweeted via her brother: "Lots of dead or dying bodies. Thought I was in a morgue."

People falsely assumed she ignored climbers in need.

"The first thing I saw was a team bringing down this woman with her face frozen solid, eyes shut and she was groaning this awful sound. Then we came across the people who had perished," she said. "That was what my tweet was about,"

Asked if she blamed overcrowding for the 2012 deaths, LeDuc was torn.

"I can't fault the crowds for being there because I wanted to be there," she said. "You can't prevent people from having these kinds of dreams. It's addictive and beautiful at the same time."

Today, LeDuc -- still eager to tick the last two summits off her list -- is on a two-year assignment in the West Bank for the Canadian International Development Agency. Kedroswki, whose blog became a way for people to follow the deadly 2012 Everest season, is writing a book about his experience.

He's also outlining potential policy that could regulate Everest like other peaks, including Mount Rainier and Mount McKinley in the United States, have in place.

Forever changed

Ben Yehuda hasn't let his damaged right hand hold him back. He's led an expedition in Georgia and solo climbed the Pyrenees. Still with the army, he's working toward degrees in law and political science.

Nadav Ben Yehuda (center) and Aydin Irmak (rightt) with Israeli ambassador to Nepal, Hanan Goder-Goldberger -- all holding their respective flags. Thomas Kelly

Large parts of the hand are still numb and he has to type school papers, but the threat of amputation has passed. Ice climbing can be painful, so he uses special equipment to support more body weight, relieving his hand of the burden.

Things will never be the same, but he's adapted. There's a joy in his voice, despite what transpired in 2012. He doesn't see his aborted attempt as a failure. After all, rescuing Irmak was a success.

The ghosts of Everest still haunt him, and the climbing notebook that accompanied him remains unopened, though he takes it with him when he goes abroad. It contains his notes and poems from that journey, but it's missing the last three days, when the rescue happened.

"One day I will have the time and peace to open and read it," he said. "I don't know what's waiting for me in there. That's the scary part. But it's with me, all the time."

Ben Yehuda echoes the words of other climbers: Everest is a choice. You can stay at the base or you can climb, but the consequences of the latter become clearer the higher you go.

"The closer you get to the summit, you suffer more and more because you have that choice, and you hate the fact that you have that choice," he said. "You always have a choice of your actions -- there is always a choice."