This leading dictionary - now in its third edition - offers wide-ranging and authoritative coverage of the earth sciences and related topics in 6,250+ clear and accessible entries. Coverage includes geology, oceanography, paleontology, minerology, volcanology, and planetary science as well as climatology, geochemistry, and petrology. It is an essential reference for students of geography, geology, and earth sciences and in related disciplines. The third edition is fully updated and includes additional coverage of process geomorphology and physical geography, plus more than 50 new line drawings to accompany descriptions of forms and processes. A new feature is an appendix of recommended web links updated on the Dictionary of Earth Sciences companion website. Additional appendices include a revised geological time scale, an updated bibliography, stratigraphic units, lunar and Martian time scales, wind-strength scales, and SI units.