Eric T. DeWeaver & Cecilia M. Bitz 
Arctic Sea Ice Decline 
Observations, Projections, Mechanisms, and Implications

Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 180.

This volume addresses the rapid decline of Arctic sea ice, placing recent sea ice decline in the context of past observations, climate model simulations and projections, and simple models of the climate sensitivity of sea ice. Highlights of the work presented here include

* An appraisal of the role played by wind forcing in driving the decline;

* A reconstruction of Arctic sea ice conditions prior to human observations, based on proxy data from sediments;

* A modeling approach for assessing the impact of sea ice decline on polar bears, used as input to the U.S. Fish and Wildlife Service’s decision to list the polar bear as a threatened species under the Endangered Species Act;

* Contrasting studies on the existence of a ‘tipping point, ‘ beyond which Arctic sea ice decline will become (or has already become) irreversible, including an examination of the role of the small ice cap instability in global warming simulations;

* A significant summertime atmospheric response to sea ice reduction in an atmospheric general circulation model, suggesting a positive feedback and the potential for short-term climate prediction.

The book will be of interest to researchers attempting to understand the recent behavior of Arctic sea ice, model projections of future sea ice loss, and the consequences of sea ice loss for the natural and human systems of the Arctic.

Table of Content

Preface

Eric T. De Weaver, Cecilia M. Bitz, and L.-Bruno Tremblay
vii

Arctic Sea Ice Decline: Introduction

Eric T. De Weaver 1

Section I: Arctic Sea Ice in the Instrumented and
Paleo-Proxy Records

Recent Trends in Arctic Sea Ice and the Evolving Role of
Atmospheric Circulation Forcing, 1979-2007

Clara Deser and Haiyan Teng 7

Reconstructing Sea Ice Conditions in the Arctic and Sub-Arctic
Prior to Human Observations

Anne de Vernal, Claude Hillaire-Marcel, Sandrine Solignac,
Taoufik Radi, and André Rochon 27

Section II: Factors in Sea Ice Sensitivity

Arctic Cloud Properties and Radiative Forcing From Observations
and Their Role in Sea Ice Decline Predicted by the NCAR CCSM3 Model
During the 21st Century

Irina V. Gorodetskaya and L.-Bruno Tremblay 47

Some Aspects of Uncertainty in Predicting Sea Ice Thinning

Cecilia M. Bitz 63

Sensitivity of Arctic Sea Ice Thickness to Intermodel Variations
in the Surface Energy Budget

Eric T. De Weaver, Elizabeth C. Hunke, and Marika M. Holland
77

The Atmospheric Response to Realistic Reduced Summer Arctic Sea
Ice Anomalies

Uma S. Bhatt, Michael A. Alexander, Clara Deser, John E. Walsh,
Jack S. Miller, Michael S. Timlin, James Scott, and Robert A.
Tomas 91

Section III: Rapid Loss Versus Abrupt Transition

Sea Ice-Albedo Feedback and Nonlinear Arctic Climate
Change

Michael Winton 111

The Role of Natural Versus Forced Change in Future Rapid Summer
Arctic Ice Loss

Marika M. Holland, Cecilia M. Bitz, L.-Bruno Tremblay, and David
A. Bailey 133

Multiple Equilibria and Abrupt Transitions in Arctic Summer Sea
Ice Extent

William J. Merryfield, Marika M. Holland, and Adam H.
Monahan 151

What Is the Trajectory of Arctic Sea Ice?

Harry L. Stern, Ronald W. Lindsay, Cecilia M. Bitz, and Paul
Hezel 175

Analysis of Arctic Sea Ice Anomalies in a Coupled Model Control
Simulation

Richard I. Cullather and L.-Bruno Tremblay 187

Section IV: The Threat to Polar Bears From Sea Ice
Decline

A Bayesian Network Modeling Approach to Forecasting the 21st
Century Worldwide Status of Polar Bears

Steven C. Amstrup, Bruce G. Marcot, and David C. Douglas
213

About the author

Eric T. De Weaver is the editor of Arctic Sea Ice Decline: Observations, Projections, Mechanisms, and Implications, published by Wiley. Cecilia M. Bitz is an American climatologist known for her research on sea ice and high latitude climate change. She is a professor in the Atmospheric Sciences Department, as well as the director of the Program on Climate Change at the University of Washington.