After introducing the concept of the birthing pool in the 1970s, Michel Odent has continuously expanded his interest in the mysterious connections between humans and water. In Planet Ocean he shows that the evolution of the oceans – particularly the fluctuations of sea levels – and the evolution of humans are inseparable. The oceans are the givers and sustainers of life, holding ninety-five per cent of the planet’s habitable space within their immense depths. Odent steers us towards a radically new vision of human nature. Our defining feature – a supersized brain – becomes a leitmotif that enables links between topics as diverse as our nutritional needs, our relationship with sea mammals, and the way members of our species give birth. He relates ‘transcendent emotional states’ with what the French writer Romain Rolland referred to as ‘the oceanic feeling’ – both suggesting the absence of limits. Access to such states can be associated with, for example, a ‘foetus ejection reflex’. This leads to the extraordinary conclusion that swimming – as learnt behaviour among humans – the birth process and access to transcendence are interrelated topics for students of human nature. Planet Ocean is a fascinating interdisciplinary study that demonstrates our manifold connections to water and suggests their relevance to everyday life.

The first edition of my book "Climate and Circulation of the Tropics" was reasonably up to date to the middle of 1985. In a second printing in 1988 it was possible to complete a few literature references and to correct some misprints. However, vigorous research has taken place over the past five years in various areas of tropical climate dynamics, especially in the atmosphere-ocean mechanisms of climate anomalies, climate prediction, ocean circulation, and paleoclimates. Promising progress has also been made in the application of general circulation modelling to tropical climate problems. In the present second edition, named "Climate Dynamics of the Tropics", I have attempted to incorporate much of the recent work to late 1990. Chapters 8 and 9 have been essentially re-written, and major additions have been made to Chapters 4 and 12 in particular. I would like to acknowledge the continued support by the U.S. National Science Foundation over the past five years. B. Parthasarathy, Poona, and H. Lessmann, San Salvador, sent me updates of data series not easily accessible. I have benefitted from discussions with numerous colleagues in the United States and overseas. In the preparation of this second edition, Marilyn Wolff patiently transferred my illegible hand-written drafts onto word processor. Dierk Polzin and Dan Skemp assisted me with the creation of the page masters and the subject index and Christopher Collimore with the author index.

The 20th Liège Colloquium was particularly well attended and these proceedings demonstrate the significant progress achieved in understanding, modelling, and observing geostrophic and near-geostrophic turbulence. The book contains more than 50 review papers and original contributions covering most aspects of the field of mesoscale/synoptic coherent structures in geophysical (oceanographic) turbulence. The properties of isolated vortices (generation, evolution, decay), their interactions with other vortices, with larger scale currents and/or with topography are investigated theoretically and by means of numerical and physical models. Observation of these dynamically important features in different parts of the world ocean are reported. Of particular interest will be the fourteen contributions by scientists from the USSR which emphasize the international character of the meeting. The book thus constitutes a useful and complete overview of the current state-of-the-art.