Ice Sheets And Climate

Climate modelling is a field in rapid development, and the fltudy of cryospheric processes has become an important part of it. On smaller time scales, the effect of snow cover and sea ice on the atmospheric circulation is of concern for long-range weather forecasting. Thinking in decades or centuries, the effect of a C02 climatic warming on the present-day ice sheets, and the resulting changes in global sea level, has drawn a lot of attention. In particular, the dynamics of marine ice sheets (ice sheets on a bed that would be below sea level after removal of ice and full isostatic rebound) is a subject of continuous research. This interest stems from the fact that the West Antarctic Ice Sheet is a marine ice sheet which, according to some workers, may be close to a complete collapse. The Pleistocene ice ages, or glacial cycles, are best characterized by total ice volume on earth, indicating that on 4 5 large time scales (10 to 10 yr) ice sheets are a dominant component of the climate system. The enormous amount of paleoclimatic information obtained from deep-sea sediments in the last few decades has led to a complete revival of iriterest in the physical aspects of the Pleistocene climatic evolution.

Our realisation of how profoundly glaciers and ice sheets respond to climate change and impact sea level and the environment has propelled their study to the forefront of Earth system science. Aspects of this multidisciplinary endeavour now constitute major areas of research. This book is named after the international summer school held annually in the beautiful alpine village of Karthaus, Northern Italy, and consists of twenty chapters based on lectures from the school. They cover theory, methods, and observations, and introduce readers to essential glaciological topics such as ice-flow dynamics, polar meteorology, mass balance, ice-core analysis, paleoclimatology, remote sensing and geophysical methods, glacial isostatic adjustment, modern and past glacial fluctuations, and ice sheet reconstruction. The chapters were written by thirty-four contributing authors who are leading international authorities in their fields. The book can be used as a graduate-level textbook for a university course, and as a valuable reference guide for practising glaciologists and climate scientists.

Written by more than 70 scientists from around the world, this publication assesses the state of the environment and the trends in ice and snow-covered regions (the cryosphere). It looks at the significance of climate changes for ecosystems and human well-being, both now and in the years to come, given that changes in ice and snow alter the distribution of the earth's heat and water, and influence regional and global ocean circulation. This publication is an official project of the International Polar Year 2007-2008.

According to my latest model for the last glacial maximum (LGM) (Grosswald 1988), the Arctic continental margin of Eurasia was glaciated by the Eurasian ice sheet, which consisted of three interconnected ice domes --the Scandinavian, Kara, and East Siberian. The Kara Sea glacier was largely a marine ice dome grounded on the sea's continental shelf. The ice dome discharged its ice in all directions, northward into the deep Arctic Basin, southward and westward onto the mainland of west-central North Siberia, the northern Russian Plain, and over the Barents shelf into the Norwegian-Greenland Sea On the Barents shelf, the Kara ice dome merged with the Scandinavian ice dome. In the Arctic Basin the discharged ice floated and eventually coalesced with the floating glacier ice of the North-American provenance giving rise to the Central-Arctic ice shelf. Along its southern margin, the Kara ice dome impounded the northward flowing rivers, causing the formation of large proglaciallakes and their integration into a transcontinental meltwater drainage system. Despite the constant increase in corroborating evidence, the concept of a Kara ice dome is still considered debatable, and the ice dome itself problematic. As a result, a paleogeographic uncertainty takes place, which is aggravated by the fact that a great deal of existing knowledge, no matter how broadly accepted, is based on ambiguous interpretations of the data, most of which are published in Russian and, therefore, not easily available to western scientists.

Chapter 1 focuses on the science to understand the physical processes and projections of mass loss of the major ice sheets in Greenland and Antarctica, as well as of mountain and other land-based glaciers. The chapter reports on current projections of glacier mass loss due to anthropogenic climate change, and in turn how that will affect sea level.The diminishment of Arctic sea ice has led to increased human activities in the Arctic, and has heightened interest in, and concerns about, the region's future as reported in chapter 2. Issues such as Arctic territorial disputes; commercial shipping through the Arctic; Arctic oil, gas, and mineral exploration; endangered Arctic species; and increased military operations in the Arctic could cause the region in coming years to become an arena of international cooperation, tension, or competition.

The issue of global warming and climate change is of continuous concern. Since the 1970s, it bas been shown that the pack-ice around the Arctic Ocean is thinning, the margin of permafrost is moving north and the vegetation in the high northern parts of the world is changing (the 'greening' of the Arctic). But are these changes the result of human activity or simply regular variations of the Earth's climate system? Over thousands of years, a continuous archive of iceberg and sea ice drift bas formed in the deep-sea sediments, revealing the place of the ice's origin and allowing a reconstruction of the surface currents and the climate of the past. However, the drift of floating ice from one place to another is not just a passive record of past ocean circulation. It actively influences and changes the surface ocean circulation, thus having a profound effect on climate change. Ice Drift, Ocean Circulation and Climate Change is the first book to focus on the interactions between ice, the ocean and the atmosphere and to describe how these three components of the climate system influence each other. It makes clear the positive contribution of paleoclimatology and paleoceanography and should be read by anyone concerned with global warming and climate change.

This authoritative new text provides a thorough, updated account of glaciers and ice sheets as monitors and indicators of environmental change. It examines the record of environmental change within glaciers and ice sheets, and that of past environments left by retreating glaciers. These themes are examined within the context of environmental change in general and global climate change in particular. Methods of using palaeoenvironmental records are assessed and the implications for future environmental change are discussed. Evidence from glacier ice left in the landscape or within the geological record, provides one of the most important sources of information on environmental change. 'Glaciers and Environmental Change' is a comprehensive account of glaciers andice sheets as monitors and indictaors of environmental change. Based on the latest research, this book consolidates a diverse range of data and explains their applications. it also assesses methods of using palaeoenvironmental records. This authoritative new text examines not only the records of environmental change within glaciers but also that of past environments left by retreating glaciers. These themes are examined within the context of contemporary debates in environmental change and the volume also seeks to draw conclusions concernign past, present and future climatic change in relation to glaciers.