Preface

This quadrennial report represents a departure from previous ones by incorporating inter‐and cross‐disciplinary articles in response to reader comments. Examples include volcanos and climates (the topic of a recent Chapman Conference); the atmospheric and hydrologic aspects of precipitation; air‐sea interaction; and surficial properties—a subject of interest to atmospheric scientists, hydrologists, planetologists, and solid earth scientists. These topics cut across two or more of the six major sections identified for the report; the major sections and their Editors are • Properties of the Solid Earth (covering volcanology, geochemistry, and petrology; geomagnetism and paleomagnetism), Ken Verosub; and • Dynamics of the Solid Earth and Other Planets (covering tectonophysics, seismology, and geodesy), Gerald Schubert; • Space Sciences (covering atmospheric studies of extraterrestrial bodies, space physics, and the Earths atmosphere from the mesosphere and above), George Siscoe. • Atmospheric Sciences(covering the Earth's atmosphere below the mesosphere), Steve Nelson; • Hydrology (including all aspects of surface and ground water), Rich Vogel; • Ocean Sciences (covering physical, chemical, and biological oceanography), Robert Weller; The authors for this volume were requested to structure their contributions into three basic segments: 1. undirected research (i.e., basic research); 2. directed research (i.e., applied research for specific applications ); and 3. development and implementation activities.