My guest today, David Keith, is among the world's experts on the subject of solar radiation

management, also known as solar geoengineering.

He's a professor of applied physics at Harvard and co-founder of Harvard Solar geoengineering

research program.

Solar geoengineering is a very tempting thing because if you want quick reduction in real

harms to some of the world's porous ecosystems, it might achieve it.

But on the other hand, it's absolutely true that if the world just chose to embrace solar

geoengineering and forgot to cut emissions, we are screwed.

Welcome to People I mostly admire with Steve Levin.

There are few areas of science that are as controversial as geoengineering.

Supporters believe it could be a valuable tool for fighting climate change, but opponents

say it's dangerous, unproven, and will weaken the will of society to take the other hard

steps required to save the planet.

In January of this year, over 60 scientists signed an open letter calling for a complete

prohibition on government funding for solar geoengineering research and a total ban on

outdoor experiments in this area.

I discovered firsthand just how sensitive the topic of geoengineering is when Stephen

Dubner and I wrote about it in our book, Super Freakonomous.

Now, I've taken many controversial and unpopular stances over my career, but nothing I've

ever written has generated as much of a negative firestorm as the suggestion that geoengineering

might play an important role in fighting climate change.

Now, that was over a decade ago.

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