George Kukla, a climate scientist who was among the first to warn of the power of global climate change and inspire government study, died on May 31 at his home in Suffern, N.Y. The cause was an apparent heart attack; he was 84.
In a career spanning more than five decades, much of it spent at Columbia University’s Lamont-Doherty Earth Observatory
, Kukla helped pioneer the modern understanding of how natural climate cycles work, and publicly warned that changing climate could affect humanity—though not in the sense that most scientists believe today. Synching climate records on land and at sea, he showed that ice ages in the last few million years were far more common than previously thought. Working from China and eastern Europe to Antarctica and Chile, he also helped to clarify the role that snow and ice, air pollutants, and other factors play in cooling earth’s climate.
In the early 1970s, Kukla became a proponent of the idea that earth was veering toward another ice age—a view shared by prominent scientists at the time, when the planet was in fact cooling. Temperatures soon reversed course, as did most researchers. Kukla did not, and stuck with his global cooling hypothesis to the end. Still, he retained the respect of colleagues, many of whom were instrumental in turning his research on its head. “He wasn’t afraid to pose ideas that were new and different,” said a former student, David Robinson, now the state climatologist for New Jersey and a professor at Rutgers University. “He just had this knack for recognizing when something was important or interesting.”
Jiří “George” Kukla was born on March 30, 1930 in Prague, Czechoslovakia, the son of Miloslav Kukla, who was then a city water engineer, and Jindriska Duskova, a seamstress who did piecework at home. A keen interest in the outdoors, especially caves, led Kukla to study geology at Prague’s Charles University, where he earned his PhD. in 1953. To earn extra money, he worked as a trolley conductor on a line that passed by the medical school where his sister and another trolley regular, Helena Kupka, studied. In a love note conveyed by his sister, Kukla asked Kupka out. They married in 1955.
Kukla went to work as a government geologist and later, a climatologist at the Czechoslovak Academy of Sciences. With the country firmly in the Soviet Union’s orbit following World War II, scientists were pressed to assist its communist allies. In 1961, Kukla and his family were sent to Cuba, where Kukla helped Fidel Castro’s regime find clay deposits for making porcelain. In his spare time, he scoured the island for climate records for his own research. The Kuklas returned home in 1966 to escalating tension with the Soviets and worsening oppression.
Kukla came to Columbia in 1971, under a one-year exchange program. The Lamont scientist who lobbied for him, Wallace Broecker
, soon became a founding father of modern climatology and was among the first to use the term “global warming.” Kukla managed to stay on, and in 1973 was hired as a senior staff scientist, eventually becoming an American citizen. Having endured Soviet rule, Kukla had learned to choose his words carefully. Once in the United States, however, he became known for his bold, often outrageous, comments.
Kukla helped champion the theory that ice ages come and go as the amount of sunlight falling on earth changes due to variations in earth’s orbit around the sun—an idea first proposed by Serbian mathematician Milutin Milanković in the 1920s and 1930s, and now well accepted.
Kukla also saw evidence that earth was now moving rapidly toward another ice age. Shortly after coming to Lamont, he organized a conference with Brown University geologist Robert Matthews on this idea. They summarized their findings in a 1972 paper in the journal Science, “When Will the Present Interglacial End?” They also wrote to President Richard Nixon of the potential for floods, snowstorms and deadly frosts, as well as “substantially lowered” food production; they warned that the Soviet Union was probably already considering a response.
Kukla used glacial dust records on land to show that ice ages over the last few million years earth were relatively common.
The White House reacted quickly. By 1973, the State Department formed a Panel on the Present Interglacial, and Congress held a series of hearings on the state of climate research and U.S. preparedness. A series of bills to create a national climate program were introduced; in 1979, President Carter signed the National Climate Program Act into law.
The global cooling story captured the public imagination, propelling Kukla into cover stories in Time and Newsweek, a BBC special, “The Weather Machine,”
and other popular media. Average temperatures had in fact been dipping in previous decades, possibly due to a short-term natural cycle and the effects of industrial smog.
Global warming would soon replace fears about global cooling, but Kukla stuck to his contention that an ice age was due soon, at least in geological terms. At a symposium he organized at Columbia
in 2000, he lengthened the time frame and put the coming ice age at 5,000 years from now. This view is not widely shared by scientists today, even without considering the warming expected from industrial carbon emissions. Because of his stance, Kukla became popular among groups that do not accept the theory of human-influenced climate change. In 2010, Kukla spoke at a meeting organized by the Heartland Institute, a political group opposed to the theory that humans are warming the climate. (Kukla did say he believed some of the current warming was coming from human—just not all of it.)
In his earlier work, Kukla showed that ice ages came and went relatively frequently over the last 2.6 million years. His evidence came from riverbanks in Czechoslovakia and Austria, where winds had deposited glacier-ground dust, or loess, during cold intervals. In a 1977 study
, Kukla linked the ice ages found in loess deposits with those in deep-sea sediments, to document many more ice ages than previously recognized. Later, he and a colleague extended this work to China’s Loess Plateau.
He also discovered that the last warm interval similar to ours today, about 130,000 years ago, was twice as long, and potentially as stable. In a 1997 study
, he suggested that the next ice age could be further away than he had earlier anticipated.
In 2003, the European Geosciences Union awarded Kukla its prestigious Milankovic Medal
; in 2011, Czech Republic President Vaclav Klaus gave Kukla
a national Medal of Merit. Despite retiring in 2001, Kukla continued to work on papers until his death. Before he passed away, the International Union for Quaternary Science organized a scientific meeting, dubbed “Kukla Loessfest,” which will be held in his honor in Poland this September.
Kukla had already cheated death many times: after eating a poisonous root in New York’s Catskill Mountains; falling into a crevasse near Antarctica’s McMurdo Station; slashing his arm with a rusted coring device on the Black Sea in the Ukraine; and suffering a heart attack while swimming in the Hudson River at the age of 76.
Once, after his station wagon broke down on the way home from a conference, Kukla coaxed it back to life by knocking the engine several times with a rock and dousing the battery with wine, recalled David Robinson, his former student. Colleagues loved Kukla’s impromptu pig roasts, which he sometimes organized in the woods near the Lamont labs, though some worried about the precarious-looking spit on which the meat and beans cooked.
“We’d come back to work coughing out smoke, smelling like we’d been battling a forest fire,” said a fellow Lamont climate scientist, Jerry McManus
. “He was more daring than most,” he added. “He liked to stir the pot a little bit.”
Kukla is survived by his wife, Helena; younger sister, Iva Mala; daughter Susan Garber; son Michael; and two grandchildren.