The environmental record in glaciers and ice sheets

Abstract

This book conveys from different points of view a sense of the variables involved in the formation and movement of glacial ice and the kinds of information held in the various glaciers. It also covers methodology and presents examples of recent findings and unexplored pathways. Verifying ice core chronology is a major challenge. Radioactive constituents such as {sup 14}C, {sup 10}Be, and {sup 81}Kr produced in the atmosphere by cosmic radiation can be useful for dating within the ranges of their respective half-lives. Abrupt changes in carbon dioxide concentration during an approximately 10,000-year period at a depth of about 2 kilometers in ice from the Dye 3 core (southern Greenland) and their evident correlation with changes in {sup 18}O values arouse great curiosity. Other abrupt (on a geologic time scale) changes in such parameters bear witness to large changes in climate in periods of a century or less. The presence of pollen testifies to the large body of unexploited information in these cores. Dating of pollen deposits, identification of species, and correlation of the resulting data with varve information on continental and ocean sediments should give new insight into climate change, species adaptation, forest migration, and back trajectories of airmore » masses.« less