Initialization Practices Disqualify UN IPCC Global Circulation Models From Use for Most Climate Change Forecast Purposes
4th February 2016
The United Nations Intergovernmental Panel on Climate Change UN IPCC features and endorses decadal global climate forecasting products. Those in turn feed into numerous downscaled regional climate forecasts. In published representations of forecast skills to date, all within this collective appear to include the poorly disclosed practice of annual boundary condition re-initializations. At one time, such initializations were isolated to obscure attempts to improve forecasts of seasonal climates (lead time 4 months). Now the initializations have become institutionalized, and they direct multi decadal predictions throughout the field of global and regional climate forecasting. The results would be more transparent to peers and the public if the true decadal history matching skills of the models (without initializations) were highlighted.