Previous TTAs on the seasonal predictability in tropical regions have been successful to initiate seasonal prediction researches and contributed to application in the developing countries. Also, targeting research and operational groups were highly appreciated by both sides and appeared to contribute efficient capacity building of seasonal prediction activities in developing countries. The experience of several TTAs suggested that two aspects of seasonal prediction are still required to be addressed for TTA to be more fruitful. 

Many operational groups, even though they are producing forecast, showed a lack of fundamental knowledge of the predictability of climate system such as initial error growth, ensemble prediction, and boundary forced signal versus noise, etc. This lack of basic knowledge hindered understanding of practical applications and its further development. Therefore, one major theme of this TTA will be providing dedicated lessons on the theoretical and fundamental aspects of climate predictability. On the other hand, it is also necessary to keep aiming practical usefulness of seasonal prediction because it has immediate social needs. Recently, researches and applications of the seasonal prediction expand its horizon into different spatial and temporal scale, partly because of obtaining higher practical utility. In particular, climate variability within a season is a state-of-art research area with high social value in planning agricultural, hydrological activities. As an advanced continuation of previous TTA on the seasonal predictability, applications on the intraseasonal predictability by the statistical approach will be another focus in this TTA. For both themes, series of laboratory experiment will be carried on using simple dynamical models, sophisticated GCM outputs, as well as statistical methods with observation dataset. 

Therefore, the 2009 TTA aims are the following;

1. Provide dedicated lessons on fundamental knowledge of predictability of weather and climate system
2. Provide an updated overview on current research on the seasonal predictability
3. Support knowledge on the intraseasonal variability and opportunity to develop simple prediction scheme through the laboratory sessions.
4. Co-ordinate co-operation between the research and operational groups of the developing countries based on the laboratory projects.