This book, first published in 2002, is a graduate-level text on numerical weather prediction, including atmospheric modeling, data assimilation and predictability.

This book contains the most recent progress in data assimilation in meteorology, oceanography and hydrology including land surface. It spans both theoretical and applicative aspects with various methodologies such as variational, Kalman filter, ensemble, Monte Carlo and artificial intelligence methods. Besides data assimilation, other important topics are also covered including targeting observation, sensitivity analysis, and parameter estimation. The book will be useful to individual researchers as well as graduate students for a reference in the field of data assimilation.

This book contains two review articles on nonlinear data assimilation that deal with closely related topics but were written and can be read independently. Both contributions focus on so-called particle filters. The first contribution by Jan van Leeuwen focuses on the potential of proposal densities. It discusses the issues with present-day particle filters and explorers new ideas for proposal densities to solve them, converging to particle filters that work well in systems of any dimension, closing the contribution with a high-dimensional example. The second contribution by Cheng and Reich discusses a unified framework for ensemble-transform particle filters. This allows one to bridge successful ensemble Kalman filters with fully nonlinear particle filters, and allows a proper introduction of localization in particle filters, which has been lacking up to now.

The demand for greater computer power in numerical weather prediction and meteorological research is as strong as ever. The world meteorological community has tried to meet this demand by exploiting parallelism. In this field, the European Centre for Medium-Range Weather Forecasts has established itself as the central venue for bringing together operational weather forecasters, climate researchers and parallel computer manufacturers to share their experiences through a series of workshops held every other year. This book reports on the latest workshop (2-6 December 1996) and is an excellent overview of the success which parallel systems have gained in meteorology worldwide, and how it was achieved. In addition, future trends in computer hardware and software development and its implications for meteorological computing are outlined.