Climate variability over the 20th Century can only be reproduced by a model when taking both natural and man-made influences into account. Predictions include: in winter, increased mean rainfall across the UK and increased maximum extremes; in summer, reduction in mean rainfall and uncertainty in extremes; sea level rise; higher storm surges; and increased drought. Uncertainties pdfs (probability density functions) are better for planners. Climate effects on the carbon cycle mean we may have to reduce emissions by 20-30% more than previously expected.