Climate Progress

I am starting a new feature and a new category here on Climate Progress for Must-have PowerPoint Slides. I’ll begin with my favorite new slide, which shows just how stable the climate has been over the 10,000-year period that allowed modern human civilization to develop and flourish (click figure for larger version):

The slide is a must-have because it captures the risk we are taking while also providing a quick visual rebuttal to a very common denier talking point, one that NASA administrator Michael Griffin of all people repeated last year (see “And the Moon is Made of Green Cheese“):

To assume that [global warming] is a problem is to assume that the state of Earth’s climate today is the optimal climate, the best climate that we could have or ever have had and that we need to take steps to make sure that it doesn’t change…. I guess I would ask which human beings — where and when — are to be accorded the privilege of deciding that this particular climate that we have right here today, right now is the best climate for all other human beings. I think that’s a rather arrogant position for people to take.

Seriously! Needless to say, his employee, James Hansen rightly called those remarks “ignorant and arrogant.” He might have added “suicidal.”

So I had to have this slide after I saw it in a recent presentation from my friend Bob Corell, chair of the Arctic Climate Impact Assessment and now Director of Global Change Programs at the Heinz Center.

And it’s not just Griffin pushing this nonsense. One of the Cato Institute climate experts currently debating the online, Indur Goklany, just advanced the following argument against my call to stabilize at 450 ppm or less:

… there is no guarantee that stabilizing CO₂ at 450 ppm would optimize human or environmental well-being. For all we know, stabilizing at 750 may be more optimal.

(more…)