50 Years Of Climate Science

(Zeb Andrews / Getty)

Robinson Meyer’s newsletter this week offers The Key Insight That Defined 50 Years of Climate Science:

Look out the nearest window and imagine, if you can, an invisible column of air. It sits directly on the tufts of grass, penetrates clear through any clouds or birds above, and ends only at the black pitch of space. Now envision a puff of heat rising through this column, passing through all the layers of the atmosphere on its journey. What happens as it rises? Where does it go? The answer to that simple question is surprisingly, even ominously important for the climate. But for nearly a century, the world’s best scientists struggled to resolve it.

The problem starts with temperature: As the intrepid puff of heat rises, it will encounter cooler air at first, then warmer air, then cooler again, until eventually it reaches the stratosphere, which is frigid. These temperature changes are paired with changes in humidity: Because hotter air can hold more water—as anyone who has endured a July day in Atlanta can tell you—the atmosphere’s warmer layers will generally have more water vapor than the cooler ones. But—and here’s the rub—water vapor is the most powerful heat-trapping gas on Earth, so it also affects air temperature. If more water is in the atmosphere, it will warm up the cooler layers.

This is complicated further by the fact that water vapor is very fickle. It falls out of the atmosphere as rain or snow after a few days and only reenters because greenhouse gases—chiefly, carbon dioxide—keep the planet’s temperature high enough for it to evaporate and rise again.

So to describe that puff of heat moving through the atmosphere, “you have to kind of include all of the temperature effects, as well as all the greenhouse-gas effects,” says Paul N. Edwards, a lead author of this year’s Intergovernmental Panel on Climate Change report and the director of the Program on Science, Technology, and Society at Stanford. The first scientist to unknit those effects and solve the riddle was Syukuro Manabe. That work won Manabe, now a 90-year-old Princeton professor, the Nobel Prize in Physics earlier this month.

Manabe is one of the first climate scientists to win the physics Nobel. (When he received the call that he had won, he reportedly exclaimed, “But I’m just a climatologist!”) He shared this year’s prize with Klaus Hasselmann, a climate scientist at the Max Planck Institute for Meteorology in Germany, and Giorgio Parisi, a theoretical physicist at Sapienza University of Rome.

Manabe’s win is a reminder that climate science was not always the politically fraught undertaking it is today—and that it is, in itself, a major scientific achievement of the past half century. Climate science emerged from the invention of the digital computer, the military and economic need to understand weather and climate, and a series of pesky questions—such as the question of heat in the air column—that pen and paper alone could not resolve.

In the 1950s, a team of American scientists started trying to describe the climate not as a set of elegant Einsteinian equations, as had been tried by the researchers before them, but as a matrix of thousands of numbers that could affect one another. This brute-force approach was borrowed from work by John von Neumann, a physicist who had used it to investigate atomic explosions. Applied to climate, it was immediately successful, producing the first short-term weather forecasts and later the first general circulation models of the atmosphere.

Manabe, who is usually called Suki, was one of several Japanese scientists invited to America in 1958 to produce these models. “The original motivation of studying [the] greenhouse effect has very little to do with my concern over environmental problem[s],” Manabe said in a 1998 interview with Edwards. Instead, he researched out of curiosity: Carbon dioxide and water vapor were the most important factors in Earth’s climate other than the sun, and he wanted to know how they worked…

Read the whole newsletter here.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s