Emission Cuts Will Fail to Stop Climate Change. What to Do Then?

Nathan Myhrvold outlines the possibilities for ‘geoengineering’ to cool the Earth and remove CO2 from the atmosphere.

By Tunku Varadarajan of The WSJ. Excerpts:

"Make no mistake—Mr. Myhrvold is concerned about climate change. But he’s a scientific realist who thinks the shibboleths on the subject—embodied in such documents as the Paris Agreement of 2016—are misbegotten. Mankind isn’t capable of reducing emissions enough to keep temperatures from rising unacceptably.

He laments that policy makers largely scorn geoengineering—human interventions in the Earth’s natural systems to thwart or neutralize climate change. Such interventions could make a difference by following two broad approaches: solar-radiation management, “which seeks to reflect sunlight back into space,” and direct air capture, which means “sucking carbon-dioxide from the sky.” While these methods may “sound crazy,” he says, “they could work.” But research of this kind is actively discouraged."

"Data from rigorous long-term CO2 measurements around the world show that “despite all the coal plants shut down, all the electric vehicles sold, all the solar and wind power deployed, all the people now working from home rather than commuting,” the concentration of CO2 continues to rise “just about as fast as it has for the past 40 years, and faster than it did in the 1960s and ’70s.”"

"Geoengineering is about “deliberately trying to reduce climate change.” Excess CO2 traps a little less than 1% of heat from the sun, “so if we could make the sun 1% dimmer, we could shut off climate change.” When Mount Pinatubo, a volcano in the Philippines, erupted in 1991, it lowered world-wide temperatures by 1 degree Celsius for about 18 months. Human-emitted particulate pollution has historically offset about 20% of human-emitted CO2. “Ironically,” he says, “the Clean Air Act made our air better but hurt climate change.”

The simplest solar-radiation management scheme, Mr. Myhrvold says, “is to emit particles in the stratosphere to mimic Mount Pinatubo."

"“Marine cloud brightening” is another solar-related intervention. “The idea is to increase the number and size of low clouds that form over the oceans so that more incoming sunlight bounces back into space instead of heating the ocean.”"

Geoengineering would appear to be the application of science par excellence. But along with the activists who “don’t want a technical solution to climate change,” he says, “there’s a second set of people who may not have that ideology, but have a more realpolitik sort of view.” This group—which comprises most Western governments—want “people to shut up” about interventions. He likens this approach to “The Little Engine That Could,” a children’s story about a small blue engine that pulled an entire train over a hill, inch by inch, through the sheer force of its will. “Opponents worry that once you have geoengineering, people won’t make sacrifices to cut emissions. They want a sword of Damocles hanging over humanity as a means to force us to follow their ideology.”

Mr. Myhrvold uses an analogy he describes as “horrible in some ways.” When the AIDS epidemic hit, some people saw it as punishment from God. “Their attitude was, ‘This is what you get if you indulge in the practices we don’t approve of.’ ” In climate change, he says, this moralistic attitude takes the following form: “I don’t like aspects of our society, I don’t like technology, I don’t like capitalism, and this is nature’s retribution. And so we have to change the way we live.” Such beliefs “have become a very powerful disincentive, particularly for academic researchers.”"