The climate is variable on all timescales. A key challenge remains the prediction of changes in climate mean, variability and extremes (high-impact weather events) for months, seasons, decades and the century ahead. On the monthly and seasonal time scale, operational probabilistic predictions, mostly based on dynamical models, are implemented in a number of Centres and practical applications are developing. On decadal to century time scales, recent model developments within projects like ENSEMBLES, CORDEX and the IPCC AR5 context provide the base to develop refined regional and global climate change projections using ensemble and probabilistic techniques. Aside from the scientific hurdles, a key challenge remains in the tailoring of such climate predictions and scenarios for end user needs and climate change impacts assessments.

The session invites papers, particularly those focusing on ensemble approaches, related to:

• Monthly, seasonal to decadal climate forecasts (predictability, multi-models, verification, calibration, downscaling, extremes, statistically based schemes, tailoring to end user needs, ..).

• Regional and global climate change scenarios (global vs. regional models, IPCC AR5, ENSEMBLES and CORDEX developments, multi-model approaches, post-processing, bias correction, statistical downscaling, quantifying model uncertainties, quantifying changes in extremes, tailoring to end user needs, ..).

• Seamless predictions: approaches to bridging the gap between weather and climate forecasts.

• Tailoring climate forecasts and longer-term projections for impacts assessments and use by societal sectors.