Forecasts of climate variability at the decadal, seasonal, interannual and decadal time scales will be discussed in this session. Results from forecast methods based both on dynamical and statistical approaches or a combination of these are welcome. The session will cover topics like ensemble forecast generation and initialization, approaches to address model uncertainty, forecast quality assessment, physical mechanisms for skill and predictability, role of anthropogenic climate change, downscaling and calibration, and demonstrations of end-user value and applications. An ENSEMBLES open session.