This is a fascinating area, because climate change really is an opportunity. The way I look at this is that the atmosphere is fragile, very fragile. From the pictures that Bob, Frank, and Koichi showed you, it's incredibly thin. Trace element analysis of that incredibly thin atmosphere is pretty important. We know from the ozone hole that if you just change chlorine content a little bit, you will really change how much ozone is out there and you will really change how much light comes to Earth's surface.
The important thing to do is to measure it and to measure it accurately. When China had its Olympics, we put seven optical instruments in the hills around Beijing. The Chinese would shut off a factory, and we would measure what would happen to the air. They would turn that factory on, shut off another one, and we would measure what would happen to the air. What they did was to optimize which factories had to be shut down to give the impression that the air was clean—