' a frisson of excitement accompanied the rumour that Eugenia Kalnay was writing a new book. Expectations were high, since she is a renowned expert in the field. She has not disappointed us.' Science and Technology ' quite wonderful, achieving a tremendous balance between comprehensiveness and readability. I am especially pleased with the numerical analysis part, which is crystal clear and shows the benefits of classroom testing. I also like the tiny little touches, like the stepped-on butterfly story and the mention that Poincaré knew about chaos in celestial mechanics. Your book fills an enormous hole in the literature of NWP [ numerical weather prediction].' Richard C. J. Somerville, Scripps Institution of Oceanography, San Diego 'Fantastic in content, format and practicability.' Kelvin K. Droegemeier, Regents' Professor of Meteorology, and Director, Center for Analysis and Prediction of Storms, University of Oklahoma '[ I] admire the clarity and pedagogic superiority of [ this] presentation.' Anders Persson, Swedish Meteorological and Hydrological Institute (SMHI) ' much better for learning about data assimilation than anything else currently available.' Richard Swinbank, United Kingdom Meteorological Office ' [ the] presentation is impeccable and is very accessible to non-meteorologists like me.' Eric Kostelich, University of Arizona ' what a great wealth of historical information.' Lawrence Takacs, NASA, Data Assimilation Office ' a delight to read It will be of great assistance to our community and should greatly encourage young scientists who may be thinking of entering the field the book will be of considerable value to people who are unable or unwilling to cope with mathematical technicalities. They can gain much by studying the expository sections of the text.' Peter Lynch, Assistant Director, Irish Weather Service ' [ the] method in the [ data] assimilation section of starting with 'baby' examples, and then working up through the full analysis, is great for understanding. On the predictability part, the history, and the explanations of how the unstable perturbations grow is the best I've seen.' Alexander E. MacDonald, Director, NOAA Forecast Systems Lab ' this book is extremely useful, informative, and well-written there are many instances where items that were only marginally familiar beforehand have now become very clear.' Brian O. Blanton, Senior Scientist/Oceanographer, University of North Carolina, Chapel Hill
