Carlos R. Mechoso is Distinguished Professor Emeritus at the Department of Atmospheric and Ocean Sciences, University of California, Los Angeles, and is currently Profesor Honorífico at the University Complutense, Madrid. He is author of more than 200 scientific publications, including pioneering contributions on numerical modeling of the coupled atmosphere-ocean system. Much of his research has focused on the El Niño/Southern Oscillation and its impacts. He has chaired international research programs on different aspects of the climate of the Americas, and is a fellow of the American and Royal Meteorological Societies. For this book, he assembled an international team of researchers working on a major topic of current scientific and societal interest.