  We describe a simple method that utilises the standard idea of bias-variance
trade-off to improve the expected accuracy of numerical model forecasts of
future climate. The method can be thought of as an optimal multi-model
combination between the forecast from a numerical model multi-model ensemble,
on one hand, and a simple statistical forecast, on the other. We apply the
method to predictions for UK temperature and precipitation for the period 2010
to 2100. The temperature predictions hardly change, while the precipitation
predictions show large changes.
