The development of seasonal and inter-annual climate forecasting

A review of the development and status of seasonal to inter-annual climate forecasting up until 2001 is presented covering not only the successes but also identifying some of the major challenges remaining. Included is discussion on the history of the enterprise; the scientific basis of modern seasonal to inter-annual prediction and its background of predictability theory; the current status of predictions and the measurement of their skill; the experiences and consequences of the 1997-1998 El Ni (n) over tildeo event; approaches to linking forecasts with applications; and a view to the future.