Madeleine: I think that slowing down climate change—the part of climate change that is due to human activities—is the only option we have. And I think that human societies are beginning to move in that direction. My question is whether they will be able to move fast enough. The speed at which ice is now disappearing from large sectors of the world suggests that there may not be a whole lot of time for dawdling. This is how I once expressed it: All anyone can say is that two extremely large and complex systems—the climate system and the human system—seem headed for confrontation, and more than anything else, it is the uncertainty of how each of these systems is likely to react to the other that makes the buildup of greenhouse gases so troubling.
And yet the climate system is fundamentally deterministic. In principle, the human system is more flexible; it has the capacity to respond to change, even the prospect of change in ways that are imaginative and innovative. The dramatic tension in the confrontation that looms in the twenty-first century emanates from that essential difference.