Preface

Since time immemorial, people have stood on the shore and wondered about the tide. The cause of the twice-daily rise and fall of sea level has attracted the attention of some of the world’s greatest scientists. To begin with, enquiry was fundamental (why are there two tides a day?), and practical (how can we predict it?). Today we realize that the tide is essential for making our planet the way it is. It is part of the process that controls the global climate and it helps make the oceans teem with life. At a local level, the tide can also be spectacular: there is nothing quite like seeing a tidal bore travelling up a river accompanied by a train of surfers.

This book is written by two scientists who continue to be surprised and intrigued by what the tide can do. The book explains how the tide is made, and how it can be measured and predicted. There are sections on tides in coastal waters, tidal bores and related phenomena, tidal friction and the slowing of the Earth’s spin, and on the tide as a great mixer of our seas and oceans. The book finishes by considering what is next in tidal studies, in our own oceans and elsewhere in the solar system. These are exciting times; space probes are due to study the possibility of life in the tide-warmed oceans on the moons of Jupiter and Saturn.

Tides: A Very Short Introduction is intended for those readers who are curious about how the tide works and why it matters to our planet. It is aimed at students and non-specialized readers wanting a succinct guide to the subject. The book avoids mathematics, instead using physical arguments, analogies, and illustrations to make a point. Examples of tides and tide-related processes are given from around the world.