There have been a few interesting bits and pieces floating round on the subject of climate models in recent days.
At WUWT, Bob Tisdale has reviewed the CMIP5 model predictions of Antarctic sea ice and found that they have performed no better than their predecessors.
Judith Curry has focused on a paper by Stevens and Bony that looks at one of the fundamental deficiencies of climate models - their inability to represent clouds - and considers the futility of trying to add complexity in other areas until this basic failing has been overcome.
And then Doug McNeall tweeted the following remarks in defence of the CMIP5 ensemble:
The CMIP5 ensemble is not set up a a calibrated probabilistic prediction system: it doesn't pretend to be one either.
It is just a set of plausible trajectories that the climate might take, given a certain set of forcings.
They're not predictions - just plausible outcomes, and those outcomes have not been borne out in practice. The models have fundamental deficiencies too.
Do the policymakers discussing the Energy Bill in Parliament today understand these issues?