Committee on Assessment of Intraseasonal to Interannual Climate Prediction and Predictability Board on Atmospheric Sciences and Climate Division on Earth and Life Studies THE NATIONAL ACADEMIES PRESS Washington, D.C. www.nap.edu THE NATIONAL ACADEMIES PRESS • 500 Fifth Street, N.W. • Washington, DC 20001 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 study was supported by the National Oceanic and Atmospheric Administration under contract number DG133R-08-CQ-0062, TO# 2. Any opinions, findings, and conclusions, or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the sponsoring agency or any of its sub agencies. International Standard Book Number-13: 978-0-309-15183-2 International Standard Book Number-10: 0-309-15183-X Additional copies of this report are available from the National Academies Press, 500 Fifth Street, N.W., Lockbox 285, Washington, DC 20055; (800) 624-6242 or (202) 334-3313 (in the Washington metropolitan area); Internet, http://www.nap.edu. Copyright 2010 by the National Academy of Sciences. All rights reserved. Printed in the United States of America The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Ralph J. Cicerone is president of the National Academy of Sciences. The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Charles M. Vest is president of the National Academy of Engineering. The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Harvey V. Fineberg is president of the Institute of Medicine. The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Ralph J. Cicerone and Dr. Charles M. Vest are chair and vice chair, respectively, of the National Research Council. www.national-academies.org COMMITTEE ON ASSESSMENT OF INTRASEASONAL TO INTERANNUAL CLIMATE PREDICTION AND PREDICTABILITY ROBERT A. WELLER (Chair), Woods Hole Oceanographic Institution, Massachusetts JEFFREY L. ANDERSON, National Center for Atmospheric Research, Colorado ALBERTO ARRIBAS, Met Office Hadley Centre, United Kingdom ROBERT E. DICKINSON, University of Texas, Austin LISA GODDARD, Columbia University, New York, New York EUGENIA KALNAY, University of Maryland, College Park BENJAMIN KIRTMAN, University of Miami, Florida RANDAL D. KOSTER, National Aeronautics and Space Administration, Greenbelt, Maryland MICHAEL B. RICHMAN, University of Oklahoma, Norman R. SARAVANAN, Texas A&M University, College Station DUANE WALISER, Jet Propulsion Laboratory, California Institute of Technology, Pasadena BIN WANG, University of Hawaii, Honolulu NRC Staff: MARTHA MCCONNELL, Study Director JOSEPH CASOLA, Postdoctoral Fellow LAUREN BROWN, Research Associate SHELLY FREELAND, Senior Program Assistant DAVID REIDMILLER, Christine Mirzayan Science and Technology Fellow v BOARD ON ATMOSPHERIC SCIENCES AND CLIMATE ANTONIO J. BUSALACCHI, JR. (Chair), University of Maryland, College Park ROSINA M. BIERBAUM, University of Michigan, Ann Arbor RICHARD CARBONE, National Center for Atmospheric Research, Boulder, Colorado WALTER F. DABBERDT, Vaisala, Inc., Boulder, Colorado KIRSTIN DOW, University of South Carolina, Columbia GREG S. FORBES, The Weather Channel, Inc., Atlanta, Georgia ISAAC HELD, National Oceanic and Atmospheric Administration, Princeton, New Jersey ARTHUR LEE, Chevron Corporation, San Ramon, California RAYMOND T. PIERREHUMBERT, University of Chicago, Illinois KIMBERLY PRATHER, Scripps Institution of Oceanography, La Jolla, California KIRK R. SMITH, University of California, Berkeley JOHN T. SNOW, University of Oklahoma, Norman THOMAS H. VONDER HAAR, Colorado State University/CIRA, Fort Collins XUBIN ZENG, University of Arizona, Tucson Ex Officio Members GERALD A. MEEHL (Chair, Climate Research Committee), National Center for Atmospheric Research, Boulder, Colorado NRC Staff CHRIS ELFRING, Director EDWARD DUNLEA, Senior Program Officer LAURIE GELLER, Senior Program Officer IAN KRAUCUNAS, Senior Program Officer MARTHA MCCONNELL, Program Officer MAGGIE WALSER, Associate Program Officer TOBY WARDEN, Associate Program Officer KATIE WELLER, Associate Program Officer JOSEPH CASOLA, Postdoctoral Fellow RITA GASKINS, Administrative Coordinator LAUREN A. BROWN, Research Associate ROB GREENWAY, Program Associate SHELLY FREELAND, Senior Program Assistant AMANDA PURCELL, Senior Program Assistant RICARDO PAYNE, Program Assistant JANEISE STURDIVANT, Program Assistant SHUBHA BANSKOTA, Financial Associate vi Acknowledgments This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the NRC’s Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their participation in their review of this report: Brian Hoskins, Imperial College London, UK Richard Kleeman, New York University Robert A. Knox, University of California, San Diego Arthur Lee, Chevron Corporation, San Ramon, CA 94583 Ruby Leung, Pacific Northwest National Laboratory, Richland, WA Robert E. Livezey, National Oceanic and Atmospheric Administration (retired), Silver Spring, MD Andrew M. Moore, University of California, Santa Cruz Sumant Nigam, University of Maryland, College Park Tim Palmer, European Centre for Medium-Range Weather Forecasts, Reading, UK Matthew C. Wheeler, Centre for Australian Weather and Climate Research, Melbourne Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations nor did they see the final draft of the report before its release. The review of this report was overseen by Roger B. Lukas (University of Hawaii). Appointed by the National Research Council, he was responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution. vii Contents Summary ......................................................................................................................................... 1 1 Introduction............................................................................................................................. 11 Scope and Purpose of this Report ........................................................................................... 11 ISI Predictability: The Example Of El Niño-Southern Oscillation ........................................ 16 Organization of This Report ................................................................................................... 20 2 Climate Prediction .................................................................................................................. 21 The Concept of Predictability ................................................................................................. 21 Sources of Predictability ......................................................................................................... 26 Methodologies Used To Quantitatively Estimate Prediction Skill ......................................... 42 Challenges to Improving Prediction Skill............................................................................... 53 3 Building Blocks of Intraseasonal to Interannual Forecasting ................................................. 54 Historical Perspective for Intraseasonal to Interannual Forecasting....................................... 54 Observations ........................................................................................................................... 56 Statistical Models.................................................................................................................... 66 Dynamical Models .................................................................................................................. 73 Data Assimilation.................................................................................................................... 79 Use of Forecasts...................................................................................................................... 87 Example of an ISI Forecast System........................................................................................ 96 Potential Improvements to ISI Forecast Systems ................................................................... 98 4 Case Studies .......................................................................................................................... 101 El Niño-Southern Oscillation (ENSO).................................................................................. 101 Madden-Julian Oscillation (MJO) ........................................................................................ 108 Soil Moisture......................................................................................................................... 116 5 Best Practices ........................................................................................................................ 124 Public Archives..................................................................................................................... 124 Metrics .................................................................................................................................. 125 More Useful Forecast Products............................................................................................. 126 Accelerated Synergy with the Research Community ........................................................... 127 6 Recommendations and Remarks on Implementation ........................................................... 129 Recommendations................................................................................................................. 129 Remarks on Implementation ................................................................................................. 135 ix x Assessment of Intraseasonal to Interannual Climate Prediction and Predictability Closing Remarks................................................................................................................... 141 References................................................................................................................................... 143 Appendix A Background Information on Statistical Techniques ............................................... 170 Appendix B Committee Members’ Biographical Information ................................................... 176