Natural Climate Variability on Decade-to-Century Time Scales (1995)
Chapter: FRONT MATTER
NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.
This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine.
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COVER: The Eye of the Storm, the oil painting reproduced on the cover of this book, is the work of Ilana Cernat of Bat-Yam, Israel. Dr. Cernat is linked to the world of intermediate-scale climate change through her son Michael Ghil, a dynamicist who has contributed substantially to our understanding of the interactions that affect climate variability. The Eye of the Storm (1989) is one of several of her paintings that express her concern for the future, particularly what sort of world we will be leaving to the generations to come. A lawyer by training and profession, Dr. Cernat began studying painting in her teens. Her work has been exhibited in Romania, Hungary, Israel, and the United States, and hangs in collections in other countries as well.
Copyright 1995 by the National Academy of Sciences. All rights reserved.
Printed in the United States of America
Editorial Committee forNatural Climate Variability on Decade-to-CenturyTime Scales
DOUGLAS G. MARTINSON (Chair),
Lamont-Doherty Earth Observatory, Columbia University, New York
KIRK BRYAN,
NOAA Geophysical Fluid Dynamics Laboratory, Princeton, New Jersey
MICHAEL GHIL,
University of California, Los Angeles
MELINDA M. HALL,
Woods Hole Oceanographic Institution, Massachusetts
THOMAS R. KARL,
NOAA National Climatic Data Center, Asheville, North Carolina
EDWARD S. SARACHIK,
University of Washington, Seattle
SOROOSH SOROOSHIAN,
University of Arizona, Tucson
LYNNE D. TALLEY,
Scripps Institution of Oceanography, University of California, San Diego
(All members of the editorial committee for this volume are former, current, or ex officio members of the Climate Research Committee)
Staff
ELLEN F. RICE, Reports Officer
MARK BOEDO, Project Assistant
DORIS BOUADJEMI, Administrative Assistant
Climate Research Committee
ERIC J. BARRON (Chair),
Pennsylvania State University, University Park
DAVID S. BATTISTI,
University of Washington, Seattle
RUSS E. DAVIS,
Scripps Institution of Oceanography, University of California, San Diego
ROBERT E. DICKINSON,
University of Arizona, Tucson
THOMAS R. KARL,
NOAA National Climatic Data Center, Asheville, North Carolina
JEFFREY T. KIEHL,
National Center for Atmospheric Research, Boulder, Colorado
CLAIRE L. PARKINSON,
Goddard Space Flight Center, National Aeronautics and Space Administration, Greenbelt, Maryland
STEVEN W. RUNNING,
University of Montana, Missoula
KARL E. TAYLOR,
Lawrence Livermore National Laboratory, Livermore, California
Ex Officio Members
W. LAWRENCE GATES,
Lawrence Livermore National Laboratory, Livermore, California
DOUGLAS G. MARTINSON,
Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York
EDWARD S. SARACHIK,
University of Washington, Seattle
SOROOSH SOROOSHIAN,
University of Arizona, Tucson
PETER J. WEBSTER,
University of Colorado, Boulder
Staff
WILLIAM A. SPRIGG, Director
MARK HANDEL, Senior Program Officer
THERESA M. FISHER, Administrative Assistant
Board on Atmospheric Sciences and Climate
JOHN A. DUTTON (Chair),
Pennsylvania State University, University Park
ERIC J. BARRON,
Pennsylvania State University, University Park
WILLIAM L. CHAMEIDES,
Georgia Institute of Technology, Atlanta
CRAIG E. DORMAN,
Department of Defense, Washington, D.C.
FRANCO EINAUDI,
Goddard Space Flight Center, Greenbelt, Maryland
MARVIN A. GELLER,
State University of New York, Stony Brook
PETER V. HOBBS,
University of Washington, Seattle
WITOLD F. KRAJEWSKI,
The University of Iowa, Iowa City
MARGARET A. LeMONE,
National Center for Atmospheric Research, Boulder, Colorado
DOUGLAS K. LILLY,
University of Oklahoma, Norman
RICHARD S. LINDZEN,
Massachusetts Institute of Technology, Cambridge
GERALD R. NORTH,
Texas A&M University, College Station
EUGENE M. RASMUSSON,
University of Maryland, College Park
ROBERT J. SERAFIN,
National Center for Atmospheric Research, Boulder, Colorado
Staff
WILLIAM A. SPRIGG, Director
H. FRANK EDEN, Senior Program Officer
MARK HANDEL, Senior Program Officer
DAVID H. SLADE, Senior Program Officer
ELLEN F. RICE, Reports Officer
DORIS BOUADJEMI, Administrative Assistant
THERESA M. FISHER, Administrative Assistant
MARK BOEDO, Project Assistant
Commission on Geosciences, Environment, and Resources
M. GORDON WOLMAN (Chair),
The Johns Hopkins University, Baltimore, Maryland
PATRICK R. ATKINS,
Aluminum Company of America, Pittsburgh, Pennsylvania
JAMES P. BRUCE,
Canadian Climate Program Board, Ottawa, Canada
WILLIAM L. FISHER,
University of Texas, Austin
JERRY F. FRANKLIN,
University of Washington, Seattle
GEORGE M. HORNBERGER,
University of Virginia, Charlottesville
DEBRA S. KNOPMAN,
Progressive Foundation, Washington, D.C.
PERRY L. McCARTY,
Stanford University, Stanford, California
JUDITH E. McDOWELL,
Woods Hole Oceanographic Institution, Massachusetts
S. GEORGE H. PHILANDER,
Princeton University, New Jersey
RAYMOND A. PRICE,
Queen's University at Kingston, Ontario, Canada
THOMAS C. SCHELLING,
University of Maryland, College Park
ELLEN K. SILBERGELD,
University of Maryland Medical School, Baltimore
STEVEN M. STANLEY,
The Johns Hopkins University, Baltimore
VICTORIA J. TSCHINKEL,
Landers and Parsons, Tallahassee, Florida
Staff
STEPHEN RATTIEN, Executive Director
STEPHEN D. PARKER, Associate Director
MORGAN GOPNIK, Assistant Director
GREGORY SYMMES, Reports Officer
JAMES MALLORY, Administrative Officer
SANDI FITZPATRICK, Administrative Associate
SUSAN SHERWIN, Project Assistant
Preface
One objective of the Climate Research Committee of the National Research Council's Board on Atmospheric Sciences and Climate is to promote progress in climate research through the organization of workshops and the preparation of reports. Over the course of a number of meetings and study sessions, the Committee began to recognize that climate variability on decade-to-century time scales had received significantly less attention than was warranted by its relevance to society. Much of climate research has focused either on seasonal-to-interannual climate variability, or on potential long-term climate change in response to human activities. These two research topics are of critical importance, but we cannot adequately address climate and climate change without also considering decade-to-century-scale variability.
Consequently, the CRC sponsored a workshop on Natural Climate Variability on Decade-to-Century Time Scales, which was held September 21-25, 1992. The conference was organized by CRC members Kirk Bryan, Michael Ghil, Doug Martinson, and Lynne Talley. It was generously sponsored by NOAA, NASA, DOE, and NSF, through the Climate Systems Modeling Program of the University Corporation for Atmospheric Research, with later assistance from EPA, USDA, the USAF Office of Scientific Research, and the Office of Naval Research. Much of the success of this workshop can be credited to the eagerness of members of the scientific community to participate and to contribute timely papers on the diverse topics that constitute this important subject.
This volume is built around the papers presented at the workshop. The organizers wished to obtain the broadest coverage of the topic possible at one meeting, recognizing that the collection of papers would be representative rather than complete and that their findings would not always be unambiguous. A commentary on each paper by its discussion leader has therefore been included, as well as an edited version of the ensuing discussion; both of these highlight uncertainties and offer additional information.
While in Irvine, the CRC selected (from among their and their panels' ranks) an expert in each of the fields represented—atmospheric and ocean observations, atmospheric and ocean models, coupled models, and proxy climate indicators—to serve as editor and first reviewer of the papers in the appropriate section of the workshop volume. To provide a context for the papers and appropriate references to germane material not covered at the workshop, the members of this editorial committee contributed an essay introducing each
section. The editors, chaired by Doug Martinson, were responsible as well for initially drafting the conclusions and recommendations, and their efforts in producing this seminal volume are greatly appreciated by the CRC. We are also indebted to Ellen Rice not only for editing the papers and discussions but for seeing the volume (and its contributors) through the entire preparation, review, and production process.
The Climate Research Committee's goal was to produce a reference document on natural climate variability on decade-to-century time scales that would encourage greater interaction among the disciplines involved and between modelers and observationalists. We hope that this volume will serve as a foundation for new and stronger research programs on climate variability on these scales, which in turn will yield a broader and sounder understanding of the climate system and enhance the predictive capability that serves our society's needs.
ERIC J. BARRON, CHAIRMAN
CLIMATE RESEARCH COMMITTEE
Table of Contents
| ||||
| Atmospheric Observations: An Essay | |||
Documenting Natural Climatic Variations: How Different is the Climate of the Twentieth Century from That of Previous Centuries? | ||||
Commentary | ||||
Variability of African Rainfall on Interannual and Decadal Time Scales | ||||
On the Initiation and Persistence of the Sahel Drought | ||||
Continental Snow Cover and Climate Variability | ||||
Commentary | ||||
