Highlighting twenty years of U.S. scientific research conducted since the International Geophysical Year (IGY) of 1957-58, this volume marks a turning point in the history of polar investigations and provides a lucid summary of the contributions of many distinguished scientists. The authors provide an overview of major polar research programs, past and present; explore concepts derived, from highly interrelated aspects of physical and life sciences; and seek to offer a glimpse of future polar science and polar development. The introduction briefly describes major physical, biological, and...