Meet the Man Who Invented Climate Science
Half a Century Ago, Syukuro Manabe Set the Stage for Modern Climate Science
When Syukuro Manabe was growing up in rural Japan during World War II, studying in a bomb shelter as military planes flew overhead, he had no intention of becoming a climate scientist. In fact, the field didn’t quite exist yet. At the time, “global warming” was a term few would have recognized, and climate science was a fledgling discipline. The youngest son of a doctor, Manabe thought he would go into medicine. But at the University of Tokyo in 1949, a different field caught his interest: weather.
Now 86 years old and a senior meteorologist at Princeton University, Manabe is still at it. During his career, he has seen climate change rise out of obscurity to become one of the most widely discussed scientific phenomena of our time. And he helped lay the groundwork for its growth: A paper he co-authored in 1967, which substantiated that increased carbon dioxide causes global warming, has been called “the greatest climate-science paper of all time.” The paper detailed the first climate model, now an indispensable tool for climate scientists.
While scientists dating back to the mid-19th century suggested carbon dioxide’s heat-trapping effect, and later studies showed rising atmospheric concentrations of the gas, Manabe and colleague Richard Wetherald were the first to deploy computer-aided data and analysis to understand the implications of those earlier findings on the earth’s climate.
Climate Models: Local Weather Predictions, Writ Large
During the early 1950s, early computers enabled more scientifically rigorous weather forecasting models. A weather model takes data—current wind speed and direction, air temperature, and humidity, for example—and plugs it into equations that describe the planet’s physics and atmosphere. The result? Weather predictions for the next few hours or days.
By the late 1950s, Manabe was working with these advanced models firsthand as a meteorologist with the United States Weather Bureau (now called the National Weather Service).
“All these weather forecasters on TV sound as if they’re the ones who predict the weather,” Manabe says. “But actually, what they say is based upon the mathematical modeling done by the National Weather Service.”
Manabe became interested in applying the recent advances in weather forecasting to studying earth’s climate. He started work for NOAA’s Geophysical Fluid Dynamics Laboratory, where his work shifted focus.
“My goal was to transform a mathematical model of weather into a mathematical model of climate,” he says. “That 1967 paper was my first attempt to do that.”
Measuring Climate Data
While meteorologists describe the daily fluctuations of things like temperature and rain, climate is about the bigger picture—the average conditions whose scope of change is not measured over hours and days, but decades and centuries.
To create a mathematical climate model, Manabe and his collaborators had to figure out what data and equations they would need to build a representation of earth’s functioning.
They also needed a powerful computer.
Using one of the first commercial computers, at Princeton, Manabe and Wetherald realized the importance of what’s called “radiative forcing.” It’s a measurement calculated using data on various atmospheric gases, including water vapor and CO2, to see how they impact the planet’s heat balance—and what happens when the proportions change.
The model predicted that a doubling of CO2 in the atmosphere would raise the atmosphere’s temperature by about 2° Celsius. Half a century later, the model is still accurate: While CO2 concentrations have yet to double since the Industrial Revolution, they have increased by about 50 percent, and the average global temperature has risen by about 1° Celsius.
The Modern Climate Model
Today’s climate models process much more data than did those in 1967, capturing information about earth’s components—oceans and sea ice, cloud cover and vegetation—and how they might change in the future. Models now also describe aspects of climate beyond temperature, such as rainfall patterns.
“These models require a large amount of computation, and as the speed of computers has increased exponentially, people have been able to develop more- and more-sophisticated models,” Manabe explains.
With these improvements, climate science now includes, and is of interest to, other disciplines. Biologists, for example, examine how warming temperatures will impact their study of species; agricultural scientists look at how drought will impact local crops; and emergency responders want to know the likelihood that their cities will be hit by storms, fires or floods.
The Future of Climate Science
Manabe says that there are still holes in the data, namely the behavior of major ice sheets. How quickly they will melt, and how much CO2 the ocean will be able to absorb, are important questions for climate scientists.
“We have to improve the part of the climate model that deals with the carbon cycle,” he says.
As models continue to improve, researchers will be able to make climate-related predictions with greater accuracy by incorporating ever more data. And these improvements are necessary to predict the increasing incidence of extreme weather events like hurricanes, floods and fires.
“The question is how to take care of this,” Manabe says. “This is why accurate projections of climate change are needed, so that people can develop strategies regarding how to moderate the harmful impacts of climate change.”
This content is produced by WIRED Brand Lab in collaboration with Western Digital Corporation.