Anthony Watts is a joke. Sorry. That site has about 20 different reasons why climate change can't be happening, or it is happening but it isn't us, or it is happening and it is us but don't worry. Science should be consistent -- that site is just throw up **** and see what sticks.

Take a look at the NASA site. You'll see a bunch of different kinds of evidence, all pointing to the same conclusion. If CO2 wasn't a green house gas, the earth would be an iceball. The fact that we've jacked up the CO2 levels in the last 100 years has to have an effect.