The El-Niño-Southern Oscillation (ENSO) is the largest climatic cycle on Earth on decadal and sub-decadal time scales, and involves changes in the coupled atmosphere-ocean system of the tropical Pacific Ocean. Although regional in its origins, the effects of ENSO radiate out into the mid- and high-latitude areas and have been linked to droughts and floods in many parts of the world, from North America to the African Sahel. Although a number of robust links (or teleconnections) have been identified between ENSO in the Pacific Ocean and weather patterns in mid-latitudes, at higher latitudes it becomes progressively more difficult to find strong connections between the phase of ENSO and the polar climates. This is the case in the Antarctic where signals of ENSO have to cross the belt of strong westerly winds, making detection of ENSO signals in the Antarctic climate records more difficult than at lower latitudes.
This book is a comprehensive account of our current understanding of the ENSO cycle written by two acknowledged experts on the subject. It is very thorough and very mathematical in places, with the emphasis being firmly on the dynamics of the phenomenon and its representation in models, rather than its climatological implications.
It begins with a helpful 20 page introductory section that covers the basics of ENSO in a very accessible style. It deals with the climate of the tropical Pacific, the phases of ENSO, observations, modelling and prediction of the cycle. Subjects that are dealt with in much more detail in subsequent chapters.
There is a comprehensive chapter on our understanding of ENSO based on the available observational data. The chapter starts with fundamental material on the radiation budget, mean climatological fields for the Pacific and ocean conditions, before examining the evolution of ENSO events. The differences between events are considered and the chapter concludes by examining how hurricane occurrences changes between El Niño and La Niña phases of the cycle.
A whole chapter is devoted to the equations of motion that are relevant to atmospheric and oceanic flow. This is followed by chapters on the boundary layer, atmospheric processes and ocean processes. A lot of the material is readily available in textbooks on dynamical meteorology and oceanography, and for me, there was too much background before the details of ENSO are dealt with. Only in chapter 7 does the discussion turn to the ENSO mechanisms, with prediction of ENSO being covered in chapter 8.
Unfortunately, the Antarctic scientist looking for information on how signals of ENSO affect the environment of the continent will not find much material in this volume. There is quite a body of literature on ENSO and the Antarctic, which was reviewed by Turner (Reference Turner2004) a few years ago. But regrettably none of these papers are covered in this book. So links between ENSO and sea ice, the climate at the coastal stations, the Antarctic Circumpolar Wave, the Antarctic Dipole and the records of ENSO found in Antarctic ice cores are not covered. The book is a very thorough account of the tropical and mid-latitude expression of ENSO and our current understanding of its origins, variability and predictability, but for information on ENSO and the Antarctic, researchers will have to look elsewhere.
