Their key argument is;
'Because reducing carbon emissions is too costly and somewhat not-so-feasible, instead let's try geo-engineering to solve the problem of climate change effectively.'
Their points are well taken. But they are missing one important thing, the big picture. The reason why many insist to reduce carbon emissions, not only because of the climate change, but also because of fossil fuel exhaustion (although it is not near future). These two issues always come together like twins. I wonder what they will respond to the question of running out of fossil fuel on earth.
Final thought. Levitt argues,
"~reducing carbon emissions, which is that it requires worldwide behavioral change, which will be hard to achieve."You may be right. But isn't it the very topic that economists have to research on, how to cause behavioral changes in market through various incentives or penalties while minimizing adverse effects?
You can explore these blogs for more information.
(Thanks to Carlos, who put these together)