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Polar Oceans from Space Atmospheric and Oceanographic Sciences Library Volume 41 Polar Oceans from Space ATMOSPHERIC AND OCEANOGRAPHIC SCIENCES LIBRARY VOLUME 41 Editors Lawrence A. Mysak, Department of Atmospheric and Oceanographic Sciences, McGill University, Montreal, Canada Kevin Hamilton, International Pacific Research Center, University of Hawaii, Honolulu, HI, U.S.A. Editorial Advisory Board A. Berger Université Catholique, Louvain, Belgium J.R. Garratt CSIRO, Aspendale, Victoria, Australia J. Hansen MIT, Cambridge, MA, U.S.A. M. Hantel Universität Wien, Austria H. Kelder KNMI (Royal Netherlands Meteorological Institute), De Bilt, The Netherlands T.N. Krishnamurti The Florida State University, Tallahassee, FL, U.S.A. P. Lemke Alfred-Wegener-Institute for Polar and Marine Research, Bremerhaven, Germany A. Robock Rutgers University, New Brunswick, NJ, U.S.A. S.H. Schneider Stanford University, CA, U.S.A. G.E. Swaters University of Alberta, Edmonton, Canada J.C. Wyngaard Pennsylvania State University, University Park, PA, U.S.A. For other titles published in this series, go to www.springer.com/series/5669 Josefino Comiso Polar Oceans from Space Josefino Comiso Cryospheric Sciences Branch, Code 614.1 NASA Goddard Space Flight Center (GSFC) Greenbelt, MD 20771 USA [email protected] ISBN 978-0-387-36628-9 e-ISBN 978-0-387-68300-3 DOI 10.1007/978-0-387-68300-3 Springer New York Dordrecht Heidelberg London Library of Congress Control Number: 2010923171 © 2010 United States Government as represented by the Administrator of the National Aeronautics and Space Administration. No copyright is claimed in the United States under Title 17, U.S. Code. All Other Rights Reserved. Published by Springer Science+Business Media, LLC 2010 All rights reserved. This work may not be translated or copied in whole or in part without the written permission of the publisher (Springer Science+Business Media, LLC, 233 Spring Street, New York, NY 10013, USA), except for brief excerpts in connection with reviews or scholarly analysis. Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed is forbidden. The use in this publication of trade names, trademarks, service marks, and similar terms, even if they are not identified as such, is not to be taken as an expression of opinion as to whether or not they are subject to proprietary rights. Cover illustration: Wave@2009 JupiterImages Corporation Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) To my wife Diana who taught me the warmth and joy of living Preface Only a few centuries ago, we knew very little about our planet Earth. The Earth was considered flat by many although it was postulated by a few like Aristotle that it is spherical based on observations that included the study of lunar eclipses. Much later, Christopher Columbus successfully sailed to the West to discover the New World and Ferdinand Magellan’s ship circumnavigated the globe to prove once and for all that the Earth is indeed a sphere. Worldwide navigation and explorations that followed made it clear that the Earth is huge and rather impossible to study solely by foot or by water. The advent of air travel made it a lot easier to do exploratory studies and enabled the mapping of the boundaries of continents and the oceans. But aircraft coverage was limited and it was not until the satellite era that full cov- erage of the Earth’s surface became available. Many of the early satellites were research satellites and that meant in part the development of engineering measurement systems with no definite applications in mind. The Nimbus-5 Electrically Scanning Microwave Radiometer (ESMR) was a classic case in point. The sensor was built with the idea that it may be useful for meteorological research and especially rainfall studies over the oceans, but success in this area of study was very limited. It turned out that one of the most intriguing applications of this sensor was in the study of the sea ice cover since the emissivi- ties of frozen and liquid sea water turned out to be very different. For centuries, the sea ice cover was just regarded as a part of the frozen North (or South) and nobody bothered to study it except the few curious scientists and explorers who felt that it has to be important since it is so vast. During the cold war, the military did a lot of research on the subject but such studies were mainly classified because the ice covered Arctic Ocean was part of a strategic warfare and was an ideal place for a well armed nuclear submarine to maneuver without being detected. It was soon realized that the sea ice cover and the polar oceans are important entities to study, not just for military but also for economic, environmental, and climatic reasons. ESMR was among the first sensors to image and characterize the entire polar regions on a daily basis. It was the first sensor to reveal the true extent and distribu- tion of the global sea ice cover as well as its seasonal variability. Data from ESMR led to many unexpected discoveries, including the existence of an unusually large Winter Polynya (unfrozen surface water within the ice pack) in the Weddell Sea in the 1970s, the size and persistence of which is counter intuitive and still a subject vii viii Preface of scientific inquiry up to this day. We have come a long way since ESMR. Many sensors much more advanced than ESMR have been launched providing us with enormous capabilities for studying the complicated processes occurring in the polar regions and the variability of many of the parameters that are being measured by satellite sensors. Satellite data are now capable of providing a detailed history of the evolution of our planet during the last three decades including that of the polar regions. This book provides introductory material about the polar oceans, more specifi- cally the ice covered areas and peripheral seas as observed by satellite sensors. I owe a lot of materials for this book from many experts in the field some of whom I worked with as co-investigators and collaborators. I specially want to express my gratitude to my NASA/Goddard colleagues including, Drs. Jay Zwally, Per Gloersen, Claire Parkinson, Chuck McClain, Frank Carsey, Bob Bindschadler, and Don Cavalieri for many years of collaborative studies. My first love was particle physics and it was Jay who made me realize that the study of the polar regions and climate is an important and a very exciting continuation of physics research. The encouragements and support of Drs. Stan Wilson, Bob Thomas and more recently, Waleed Abdalati, Seelye Martin, and Tom Wagner who managed or manages the Cryospheric Sciences Program at NASA headquarters made it possible for me to do polar research at GSFC over the years. I am especially grateful to Dr. Norbert Untersteiner and Dr. Willy Weeks for many in-depth discussions about the polar climate system and the intricate processes associated with the sea ice cover. I have benefited from close collaborations with Drs. Arnold Gordon, Peter Wadhams, Stan Jacob, Steve Ackley, Manfred Lange, Neal Sullivan, Walker Smith, Koni Steffen, Rob Massom, and Ron Kwok. The writing of this book was started in 2006 while I was a fellow of the Japanese Society for the Promotion of Science and working as a Guest Professor at Chiba University, and I am grateful to Prof. Fumihiko Nishio, who was my host, for his encouragements and kind hospitality. Larry Stock of SGT and Robert Gersten of Adnet/RSIS have provided me excellent program- ming and analysis support at GSFC during the last several years, and I appreciate very much their dedicated efforts. Last but not least, I wish to thank my wife, Diana, my sons Glen and David and my daughter Melissa for encouragements and patience not just during the period of book writing but throughout my entire career as a polar researcher and adventurer. Many useful comments and suggestions were provided by Drs. Arthur Cracknell of the University of Dundee, UK, Markus Thorston, Head of the NASA Cryospheric Sciences Branch, Lawrence Mysak of McGill University and Edward Hanna of the University of Sheffield, UK. My daughter Melissa, daughter-in-law Cindy, and my wife Diana also provided some editorial help. While writing this book, my mother, who had been a great source of inspiration all my life, died at the age of 100 years. It was an enormous personal loss for me, my brothers, and sisters but it is wonderful to realize that we can live to be centenarians and are able to experience a significant window of our changing planet and its changing climate. Our current collection of continuous satellite data is only a few decades long but we have undoubtedly learned a lot from them about the Earth’s Preface ix environmental and climate system and personally observed the subtle but important changes since the launch of Sputnik in the late 1950s. With all the satellite data we now have and with the advent of international ventures like the Global Earth Observation System of all Systems (GEOSS), we will find the answers of many of our current questions, but at the same time, we will undoubtedly find many more questions that need to be answered. The advances in our understanding of the Earth’s climate engine, including the impact of the polar oceans have been tremen- dous and we look forward to being able to forecast effectively the state of our planet in the immediate and foreseeable future. Greenbelt, MD Dr. Josefino Comiso Contents 1 Background ............................................................................................... 1 1.1 Introduction .......................................................................................
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