Between 20 and 24 June 2011, a workshop was held at ECMWF on 'Representing Model Uncertainty and Error in Weather and Climate Prediction'. The workshop was co-sponsored by WMO/WGNE, WMO/THORPEX, WCRP.
The workshop attracted almost 100 participants, from Europe and other parts of the world, such as Japan, North and South America and Australia.
There are a number of techniques to represent model uncertainty in ensemble forecasts. These range from the multi-model techniques which feature prominently in IPCC assessment reports, to the stochastic parametrisations pioneered at ECMWF and widely used at weather forecast centres around the world. A key outcome of the meeting was that the stochastic parametrisation paradigm needs further development at the process level, and hence needs to be incorporated as part of general parametrisation development. Key tools will include sophisticated analyses of observational datasets, output from cloud resolving models, and analyses from objective data assimilation. Data assimilation techniques themselves will benefit from better representations of model uncertainty.
