evidence: A recent article in the eminent US magazine Science questioned how the IPCC will deal with some climate models which "run hot". Some models, it said, have projected global warming rates "that most scientists, including the model makers themselves, believe are implausibly fast". [...] Climate models comprise millions of lines of computer code representing the physics and chemistry of the processes that make up our climate system. The models run on powerful supercomputers and have simulated and predicted global warming with remarkable accuracy. [...] For a few years now, scientists have known some new-generation climate models probably overestimate global warming, and others underestimate it.