RealClimate

The Internet wasn't invented for RealClimate specifically, but it's hard to imagine a site more in line with the Web's original purpose: scientific communication. An assembly of climate researchers gives readers what's lacking virtually everywhere else — straightforward presentation of the physical evidence for global warming, discussed with patience, precision and rigor, and, quite often, length, such as in a 2,300-word evisceration of Michael Crichton's work of fiction, State of Fear. Never mind that the Sun appears to be falling into the ocean in RealClimate's banner.

Sample RealClimate post: [Crichton] also gives us his estimate, ~0.8 C for the global warming that will occur over the next century and claims that, since models differ by 400% in their estimates, his guess is as good as theirs. This is not true. The current batch of models have a mean climate sensitivity of about 3 C to doubled CO2 (and range between 2.5 and 4.0 degrees)..., i.e., an uncertainty of about 30%. As discussed above, the biggest uncertainties about the future are the economics, technology and rate of development going forward.