What do you think of the new US-India and US-China agreements on climate change and clean energy?

Certainly, none of this is bad, but it's a lot of talk at this point. The U.S. needs to put into law commitments for reducing greenhouse emissions before other countries take us seriously. That said, Europe in general, and U.S. state and local governments have already made some key commitments and have reduced greenhouse emissions, independent of national legislation, which is a good indicator that some are motivated to solve this great challenge. There are many committed folks working on improving efficiency of solar power and other renewables, in part due to large incentives for these industries. I'm encouraged by this. The argument from fossil fuel lobbies will become progressively weaker as their product becomes progressively less feasible compared to alternatives. Keep pushing forward.