Dr John Theon, the retired scientist formerly in charge of key NASA climate programs who supervised James Hansen — the activist-scientist who helped give the manmade global warming hypothesis centre prominent media attention — has come out as a skeptic about man-made global warming.

“My own belief concerning anthropogenic climate change is that the models do not realistically simulate the climate system because there are many very important sub-grid scale processes that the models either replicate poorly or completely omit,” he said. “Furthermore, some scientists have manipulated the observed data to justify their model results. In doing so, they neither explain what they have modified in the observations, nor explain how they did it.

“They have resisted making their work transparent so that it can be replicated independently by other scientists. This is clearly contrary to how science should be done. Thus there is no rational justification for using climate model forecasts to determine public policy.”