COLUMBUS, Ohio — One day in 1991, high in the thin, crystalline air of the Peruvian Andes, Lonnie G. Thompson saw that the world’s largest tropical ice cap was starting to melt. It was the moment he realized that his life’s work had suddenly become a race.
俄亥俄州哥伦布——1991年的一天，秘鲁安第斯山区的高处，稀薄澄净的空气之中，朗尼·G·汤普森(Lonnie G. Thompson)目睹世界上最大的热带冰冠开始融化。正是在那一刻，他猛然意识到，这辈子的工作已经变成了一场速度竞赛。
The discovery meant other ice caps were likely to melt, too, and the tales of past climate that they contained could disappear before scientists had a chance to learn from them.
Driven by a new sense of urgency over the ensuing 20 years, he pulled off a string of achievements with few parallels in modern science. He led teams to some of the highest, most remote reaches of the earth to retrieve samples of the endangered ice.
Then last October, the race against the clock became much more personal.
Dr. Thompson woke up in a Columbus hospital room, a strange dream rattling in his brain. He looked down. “Wires were coming out of my chest,” he said. Machinery had been implanted to keep him alive. Longer term, doctors told him, only a heart transplant would restore him to full health.
Dr. Thompson, 64, is one of the most prominent of the generation of scientists who, in the latter decades of the 20th century, essentially discovered the problem of global warming. Now those scientists are beginning to age out of the field. Many of them say they grapple with the question of how hard to keep pushing themselves. Could one more finding or one more expedition help turn the tide of public awareness?
Some have continued working into their 70s and 80s. One of the most vocal about the need for action, Stephen H. Schneider of Stanford University, fought off a rare form of cancer several years ago, only to die of a blood clot in 2010 after speaking in Europe about climate change. He was 65.
有些科学家一直工作到了七八十岁的时候。说到行动的必要性，声音最大的科学家之一就是斯坦福大学的斯蒂芬·施奈德(Stephen H. Schneider)。他在几年前战胜了一种罕见的癌症，最后却在2010年死于血凝，年仅65岁。去世之前，他还在欧洲发表了关于气候变化的演讲。
Of this pioneering group, few were hardier than Dr. Thompson, who has taught earth sciences at Ohio State University since the 1970s. Though he routinely spent up to two months a year camped in dangerous conditions atop mountains, he despised derring-do. His enterprise was driven by a lust for hard data.
Hauling six tons of equipment to South America, Africa, Asia and Europe, he and his small team raced to recover long cylinders of ice from glaciers that had built up over thousands of years. The layers in those cylinders contained dust, volcanic ash, subtle variations in water chemistry, even the occasional frozen insect — a record of climatic and geologic changes that could be retrieved, preserved and interpreted like a series of tree rings.
Dr. Thompson became one of the first scientists to witness and record a broad global melting of land ice. And his ice cores proved that this sudden, coordinated melting had no parallel, at least not in the last several thousand years.
To some climate scientists, the Thompson ice core record became the most convincing piece of evidence that the rapid planetary warming now going on was a result of a rise in greenhouse gases caused by human activity.
“The reason Lonnie’s stuff is so powerful is that it’s so simple,” said Daniel P. Schrag, a geochemist at Harvard and director of its Center for the Environment.
哈佛大学地球化学家、环境中心主任丹尼尔·P·施拉格(Daniel P. Schrag)说：“朗尼的材料无比有力，原因就是它无比简明。”
“His evidence dismisses the idea that this is some sort of 300-year or 500-year cycle, which is what the skeptics and the deniers want to say. You say: ‘No, because Lonnie’s ice didn’t melt then. It’s melting now, but it didn’t melt then.’ ”
Colleagues say Dr. Thompson neglected his own health in pursuit of his science. Now, largely confined to his office and home in Columbus, he said he has begun to appreciate the clarity afforded him by his circumstance.
“I wouldn’t wish it on anyone, but it’s not all bad,” he said. “It really forces you to sit down and think about what it is you’re doing and why you’re doing it, and how you are using your time.”
Drawn to the Tropics
Raised on a farm near Gassaway, W.Va., Lonnie Gene Thompson arrived at Ohio State with the idea of becoming a coal geologist, but ice soon seduced him.
朗尼·吉恩·汤普森(Lonnie Gene Thompson)生长在靠近西弗吉尼亚加萨韦的一个农场里，来俄亥俄州的目的是成为一名煤炭地质学家。但是，没过多久，他就变成了冰的俘虏。
As a graduate student pursuing a doctorate in geology, he was put to work analyzing dust in ice cores retrieved from Antarctica, and he learned how minute chemical and physical features could be used to deduce past climate. Thompson was drawn to tropical ice.
The very idea of ice in the warmest part of the world seems to defy common sense. But it is cold atop high mountains everywhere, and major ice caps exist on towering mountain plateaus far from the earth’s poles. Even in the mid-20th century, some of them had never been explored.
The Ohio State team decided to focus on the mighty Quelccaya ice cap in the Andes of Peru, the largest tropical ice cap on the planet, suspecting it might yield a climate record. But the idea of drilling there met a chilly reception from some of the most eminent climate scientists of the day. The prevailing notion in the 1970s was that the tropics were climatologically boring and that most of the big oscillations in the earth’s climate had happened nearer the poles.
Besides, in the tropics, “nobody thought there would be ice that would be very old,” recalled Wallace S. Broecker of Columbia University, then and now the leading American paleoclimatologist (At 80, Dr. Broecker is among the climate scientists still working long past retirement age).
除此之外，“谁都没想到热带地区还会有极其寒冷的冰层。”哥伦比亚大学的华莱士·S·布洛克(Wallace S. Broecker)回忆道。不管是当时还是现在，布洛克都是美国古气候研究领域的权威专家（布洛克今年80岁，是那些远远超过退休年龄却仍然坚持工作的气候学家当中的一员）。
In 1974, with $7,000 from the National Science Foundation, Dr. Mercer and Dr. Thompson led a scouting party to Quelccaya, on a volcanic plain 18,000 feet above sea level. They confirmed that annual layering caused partly by seasonal dust could be seen in the ice.
1974年，带着美国国家科学基金会(National Science Foundation)赞助的7000美元，默塞尔(Dr. Mercer)和汤普森领着勘测队去了奎尔卡亚，奎尔卡亚位于一个海拔18000英尺的火山平原之上。他们证实，那里的冰确实带有部分由季节性灰尘造成的年纹层。
After a series of frustrated attempts to drill through the ice, including one involving a helicopter, Dr. Thompson resorted to mules, horses and donkeys to mount a 1983 expedition that drilled through 537 feet of ice with a solar-powered drill.
At the time, he could not find a way to get the ice home frozen, so the layers were teased apart on the mountain and melted into thousands of plastic bottles that were hauled back to Columbus for chemical analysis.
The results were startling. The ice record stretched back 1,500 years, and it recorded huge oscillations in the climate of the region — intense dry spells alternating with wet spells. Vast lakes had come and gone in the valleys, the dust from their dried-up beds leaving chemical imprints in the ice. The record also showed changes in water chemistry similar to those seen at the poles, leading Dr. Thompson to infer major temperature swings in the tropics.
In the next few years, Dr. Thompson drilled at other sites in South America, recovering ice as old as 25,000 years and confirming the patterns seen at Quelccaya. His results, along with records other scientists were gathering from the sea floor, roiled the field of paleoclimatology.
A realization began to dawn that the tropics were important to global climates of the past. It had been clear since the 1970s that the ice ages were caused by wobbles in Earth’s orbit around the Sun, but the ice sheets mainly grew in the Northern Hemisphere, which has most of the world’s land. Scientists had evidence that the ice sheets influenced climate all over the planet, but they had had trouble figuring out how.
Dr. Thompson’s results became part of a growing body of science suggesting that signals were being transmitted from the North Pole to the South Pole via the tropics, through huge shifts in winds, rain patterns and other variables.
The work had implications in other fields, too. Some archaeologists had begun to think climate swings were responsible for the rise and fall of cultures in the Andes and along the Peruvian coastal plain. And Dr. Thompson’s ice cores gave them evidence that climate had indeed changed drastically enough to send entire civilizations into collapse.
A Series of Challenges
By the late 1980s, concern about global warming was rising, and some scientists believed the ice caps and glaciers of the tropics would be among the first to show the effects.
On a return trip to Quelccaya in 1991, Dr. Thompson noticed substantial melting at the edges of the ice cap, and some on top. Laboratory tests confirmed that the annual climate signals recorded in the chemistry of the ice were being blurred.
He picked up the pace with his team, who were among the first Western scientists allowed onto the ice caps of highland China, retrieving ice that may be as old as 750,000 years. He drilled several other times on the Tibetan plateau, in the Russian Arctic, in Alaska, atop Mount Kilimanjaro in Tanzania, in New Guinea, in the Alps.
In his book about Dr. Thompson, “Thin Ice,” published in 2005, Mark Bowen described an incident on a peak called Huascarán in Peru. Dr. Thompson’s tent collapsed and started blowing off the mountain with him inside; he managed to stop it only by driving an ice ax through the floor, and then waited out the night. In his travels, he forded flooding rivers on horseback and coped with altitude sickness, coughing fits and blinding headaches. His West Virginia farm upbringing came in handy as he challenged Mongol porters to contests shooting wild game. Other times, he went hungry. Once, in China, dinner was a bowl of stewed camel paws.
2005年，马克·鲍恩(Mark Bowen)出版了一本有关汤普森的书，书名是《如履薄冰》(Thin Ice)。书中描述了一件发生在秘鲁瓦斯兰峰(Huascarán)的事情，风把汤普森的帐篷吹塌了，又把帐篷吹向山下，捎带着帐篷里面的汤普森；他把冰斧扎进地面，这才勉强停了下来，之后就眼巴巴地等到了天亮。旅程之中，他曾经骑在马背上涉过洪水泛滥的河流，还经历过高原病、阵发性咳嗽和苦不堪言的剧烈头疼。当他叫板蒙古搬运工、跟他们比试狩猎的时候，他在西弗吉尼亚农场的成长经历就派上了用场。还有些时候，他只能忍饥挨饿。有一次在中国，他的晚餐是一碗炖骆驼蹄子。
Somehow he and his team got the ice they were after and found ways to haul tons of the frozen cylinders back to Columbus, where roughly four miles of ice cores are kept at 30 degrees below zero and protected by backup generators.
Dr. Thompson’s career has not been entirely free of controversy.
During an expedition to Tibet in 1997, a graduate student working with him, Shawn Wight, was forced off the mountain by altitude sickness, got an infection while hospitalized and died. A judge found Ohio State not liable, but the case led universities across the country to re-examine their policies on field expeditions.
Some scientists have challenged Dr. Thompson’s analysis of the signals in his ice cores, saying that the chemical changes he interprets as temperature swings probably reflect a more complicated mix of changes in temperature, precipitation and atmospheric circulation patterns. Mathias Vuille, an atmospheric scientist at the State University at Albany, who admires Dr. Thompson’s achievements, said that his analysis on this point “is hard to reconcile with other evidence.”
And an especially intense controversy has erupted about Dr. Thompson’s interpretation of ice he recovered atop Mount Kilimanjaro. Though Dr. Thompson sees the rapid disappearance of ice there as a reflection of climate change, his critics cite more regional than global factors, like precipitation.
While Dr. Thompson has defended his interpretations on these points, he does have some regrets. One is that those years of frenzied drilling led him to fall behind in publishing his data, so some of the evidence he has gathered is not yet available to the broader scientific community.
Still, it is clear that Dr. Thompson managed to retrieve ice cores from a half-dozen places in the world where they can no longer be found in pristine form today. Some of the ice he drilled on Kilimanjaro, for instance, has since disappeared entirely.
Ellen Mosley-Thompson does most of her fieldwork in Antarctica, but she has played a major role in interpreting the ice her husband recovered. Both are convinced that their own analysis is merely a start, and they have put money they have won from scientific prizes into an endowment to preserve the ice cores for future generations.
‘It’s Not Your Time’
As a young man, Dr. Thompson stayed in shape by training for and running marathons. He now realizes his health began a slow decline sometime in his 40s.
Dr. Bowen, a physicist and mountain climber, accompanied Dr. Thompson on several expeditions to write the definitive book about him. He said that atop Mount Kilimanjaro, “my heart went out to Lonnie as I lay in my tent at 20,000 feet and listened to him just hack away, coughing his lungs out. It happened almost every night for four weeks, yet we were all amazed when he got up during the day and was still as productive as four normal people.”
Fifteen years ago, Dr. Thompson was treated for asthma, but he now suspects that the diagnosis was incomplete. He learned in 2009 that he had congestive heart failure, but kept to a schedule of expeditions to New Guinea and the Alps.
For a time, “he was in complete denial,” his wife said. His doctors cannot say for certain that his work contributed to his health problems. Dr. Thompson notes that he has a family history of heart disease.
Last fall, he reached a point where he could barely walk. He wound up in the hospital, drifting in and out of consciousness for days as his failing heart struggled to keep him alive. More than once, his wife and their daughter, Regina, were told he might not survive the night.
It was deep in one of his comatose periods, he figures, that he had the dream. He described jumping through space and landing in a beautiful spot filled with flowers and streams. There, he said, a figure in white spoke to him.
“It’s not your time,”’ the figure told him. “You have another purpose.”
Dr. Thompson is not a particularly religious man, and he does not try to explain the dream, but his memory of it is vivid.
The battery-powered equipment doctors implanted in his chest helped him get better and leave the hospital as he waited on the organ list. By the spring, he had resumed a limited work schedule, cranking out papers with colleagues around the world.
He was at his desk on May 1 when the phone rang. He walked next door to his wife’s office.
“My heart is here,” he told her.
He underwent the transplant that evening. The donor’s family most likely does not know that the decision they made saved the life of a world-famous scientist. He is writing a letter in hopes of thanking them some day.
Back in his office in early June, after the transplant, his face glowed a healthy pink. “I feel better than I have in 20 years,” he said.
Dr. Thompson knows he needs to go slowly, but he has already started eyeing an unexplored ice cap in China.
One of the greatest achievements of modern climate science was the recovery of ice cores in Antarctica that allowed a detailed reconstruction of the earth’s climate for the past 800,000 years. Dr. Thompson suspects an even longer record could be recovered by drilling at the right spot in Tibet.
Last year, he pulled strings in Russia and asked for an astronaut on the International Space Station to photograph a certain ice cap. A Chinese scouting party has already checked it out, and drilling a core seems possible, if he regains his strength.
Other people could probably do it without him, but that is not a thought he cares to entertain.
“I’m going back,” he said with a wide grin. “I’m looking for the oldest ice on the planet.”