Climate models used by IPCC fail to predict past climate patterns

By Robert Zimmerman:
A recent paper published in Hydrological Sciences Journal states that climate models used by IPCC cannot even predict known past climate patterns. Key quote:

It is claimed that GCMs [General Climate Models] provide credible quantitative estimates of future climate change, particularly at continental scales and above. Examining the local performance of the models at 55 points, we found that local projections do not correlate well with observed measurements. Furthermore, we found that the correlation at a large spatial scale, i.e. the contiguous USA, is worse than at the local scale. However, we think that the most important question is not whether GCMs can produce credible estimates of future climate, but whether climate is at all predictable in deterministic terms.

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