Dr. Anthony (Tony) Hollingsworth, was one of the main contributors to the Global Energy and Water Cycle Experiment programme (GEWEX). His enthusiasm for the observations, modeling, and process studies undertaken by the various continental scale experiments of GEWEX proved valuable, particularly to the numerical weather predication centers and later to the hydrologic services.

This presentation will focus on two aspects of research, namely remote sensing and data assimilation and ensemble predication (including uncertainty analysis) in hydrology, which were highly influenced by Tony's vision for GEWEX. In the first part there will be a brief review of some recent work on high resolution global precipitation estimates from satellites. The second part will focus on data assimilation and ensemble forecasting related to hydrology. The ideas of data assimilation and ensemble forecasts, which were influenced by Tony, have been adopted by many branches of the Earth Sciences, including hydrology.

Examples of results from the GAPP (GEWEX Americas Prediction Project) will be presented.