Read other letters about this article
wrote:GCMs (computer climate models) do not validate a hypothesis. It takes physically observed hard data to validate the greenhouse hypothesis, and this is lacking today.
Baloney. To validate a hypothesis one takes the measured data and compares them to the results of calculations incorporating the relevant physics. This is exactly what has been done. You could claim that the models are not good enough yet, and I would agree that more needs to be done to make the results more accurate. But you misunderstand the process and the result.