This book presents the latest progress in data assimilation in meteorology, oceanography, and hydrology, including the land surface. It spans both theoretical and applied aspects, using 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, parameter estimation, and AI applications. The book will be useful to individual researchers and graduate students as a reference in the field of data assimilation.
