“Water, water, every where, — nor any drop to drink” (Samuel Taylor Coleridge, “The Rime of the Ancient Mariner”) aptly sums up the overall picture of the hydrosphere — that part of planet Earth made up of water. The oceans, covering 71% of the surface of the globe, make up 97.25% of the mass of water. Most of the freshwaters, whose volume is estimated to be 39·106 km3, are also not immediately accessible: 29·106 km3 is ice accumulated on mountain glaciers and on the ice caps of the poles; 9.5·106 km3 constitute groundwaters and only about 0.13·106 km3 are surface waters, mainly lakes and rivers. The amount of water held up in the biosphere is estimated to be 0.6·103 km3. The atmospheric moisture amounts to just 13·103 km3 — less than 10−5 of the total amount of water — but this small amount is the one which actuates the hydrologic cycle by virtue of its dynamic nature. <...>

Although (Soddy, Nature 92:399–400, 1913) inferred the existence of isotopes early last century, it was not until the discovery of the neutron by (Chadwick, Nature 129:312, 1932) that isotopes were understood to result from differing numbers of neutrons in atomic nuclei. (Urey, J Chem Soc 1947:562–581, 1947) predicted that different isotopes would behave slightly differently in chemical (and physical) reactions due to mass differences, leading to the concept of isotopic fractionation.

Improved understanding of the Earth’s water cycle is a key element of global efforts to develop policies and practices for the sustainable management of water resources. Isotope and nuclear techniques have provided unmatched insights into the processes governing the water cycle and its variability under past and present climates. The International Atomic Energy Agency (IAEA) convened the first symposium on isotope hydrology in 1963. As isotope hydrology developed as an independent discipline, the IAEA symposia, convened every four years, provided a vehicle to review the state of the science and discuss future developments. Proceedings of these symposia contain classical papers that still form the basis of a number of applications in hydrology and inspire current research. <...>

This book contains a comprehensive presentation of all aspects of isotope geoscience and is intended to be used in universities and colleges as a textbook in lecture courses for senior undergraduate and first-year graduate students in the earth sciences. In addition, this book will serve as a source of information for professionals in the earth sciences and related disciplines. The encyclopedic function of this book is enhanced by a detailed table of contents and by author and subject indexes. The book also contains a large number of original diagrams with extended captions that facilitate browsing and convey information without requiring close reading of the text. In addition, each chapter contains cross-references to other parts of the book where related information can be found <...>