The goal of the GEWEX Americas Prediction Project (GAPP) is to address the role of land surface in climate prediction based on emerging scientific understandings, new observational technologies and the improved capability of modelling the coupled land-atmosphere system. GAPP has two primary objectives, i.e., to improve predictions of key hydrological variables (such as precipitation, soil moisture, runoff) and to use the improved predictions for better water resource management applications. The GAPP research areas include predictability in land-surface processes, orographic effects on hydrologic cycle, predictability in monsoonal systems, integration of predictability into prediction systems, model transferability studies, CEOP (Coordinated enhanced Observing Period), and the water resources applications. GAPP is a follow-on project to the GEWEX Continental International Project (GCIP). GCIP focused on the geographic area of Mississippi River Basin. GAPP has extended the geographic area to include the northwest and southwest of US.

This paper will present the GAPP implementation strategy and describe major near-term and long-term activities. The paper will describe GAPP organizational structure, implementation time line, data management strategy and linkages between GAPP and other programs. Specific implementation issues including dataset development, modelling, process studies, and field campaigns in each research area will be discussed.