Review of the U.S. Climate Change Science Program's Draft Synthesis and Assessment Product 2.4: Trends in Emissions of Ozone Depleting Substances, Ozone Layer Recovery, and Implications for Ultraviolet Radiation Exposure (2007)

Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Review of the U.S. Climate Change Science Program’s Draft Synthesis and Assessment Product 2.4: Trends in Emissions of Ozone Depleting Substances, Ozone Layer Recovery, and Implications for Ultraviolet Radiation Exposure Committee to Review the U.S. Climate Change Science Program’s Draft Synthesis and Assessment Product 2.4 Board on Atmospheric Sciences and Climate Division on Earth and Life Studies 

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. Support for this project was provided by the Department of Commerce/National Oceanic and Atmospheric Administration (NOAA) under Contract No. DG133R07SE2247. Any opinions, findings, and conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the organizations or agencies that provided support for the project. International Standard Book Number – 13: 978-0-309-11525-4 International Standard Book Number – 10: 0-309-11525-6 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 2007 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 TO REVIEW THE U.S. CLIMATE CHANGE SCIENCE PROGRAM’S DRAFT SYNTHESIS AND ASSESSMENT PRODUCT 2.4 M. JOAN ALEXANDER (Chair), NorthWest Research Associates, Boulder, Colorado DEREK CUNNOLD, Georgia Institute of Technology, Atlanta TERRY DESHLER, University of Wyoming, Laramie STEVEN LLOYD, The Johns Hopkins Applied Physics Laboratory, Laurel, Maryland MACK MCFARLAND, DuPont Fluoroproducts, Wilmington, Delaware MICHELLE SANTEE, Jet Propulsion Laboratory, Pasadena, California THEODORE G. SHEPHERD, University of Toronto, Ontario, Canada MARGARET TOLBERT, University of Colorado, Boulder DONALD WUEBBLES, University of Illinois, Urbana NRC Staff LEAH PROBST, Study Director KATIE WELLER, Senior Program Assistant v 

BOARD ON ATMOSPHERIC SCIENCES AND CLIMATE F. SHERWOOD ROWLAND (Chair), University of California, Irvine M. JOAN ALEXANDER, NorthWest Research Associates, Boulder, Colorado MICHAEL L. BENDER, Princeton University, New Jersey ROSINA M. BIERBAUM, University of Michigan, Ann Arbor CAROL ANNE CLAYSON, Florida State University, Tallahassee WALTER F. DABBERDT, Vaisala Inc., Boulder, Colorado KERRY A. EMANUEL, Massachusetts Institute of Technology, Cambridge DENNIS L. HARTMANN, University of Washington, Seattle PETER R. LEAVITT, Weather Information, Inc., Newton, Massachusetts VERNON R. MORRIS, Howard University, Washington, D.C. THOMAS H. VONDER HAAR, Colorado State University/CIRA, Fort Collins Ex Officio Members ANTONIO J. BUSALACCHI, JR., University of Maryland, College Park NRC Staff CHRIS ELFRING, Director IAN KRAUCUNAS, Program Officer CURTIS H. MARSHALL, Program Officer CLAUDIA MENGELT, Program Officer LEAH PROBST, Research Associate ROB GREENWAY, Senior Program Assistant KATHERINE WELLER, Senior 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 National Research Council’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 review of this report: James G. Anderson, Harvard University, Cambridge, Massachusetts Greg Bodeker, National Institute of Water & Atmospheric Research Limited, Auckland, New Zealand Mary Anne Carroll, University of Michigan, Ann Arbor Veronika Eyring, Institut für Physik der Atmosphäre, Wessling, Germany Vitali Fioletov, Environment Canada, Downsview, Ontario, Canada Ross J. Salawitch, University of Maryland, College Park 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 Marvin Geller, The State University of New York, Stony Brook. 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 ......................................................................................................3 References...................................................................................................................4 2 OVERARCHING COMMENTS................................................................................6 Relationship between Ozone and Climate ..................................................................6 Assessing U.S. Contributions to Ozone-depleting Substances and Radiative Forcing ..............................................................................................7 Research Needs.........................................................................................................10 Policy Implications ...................................................................................................11 Presentation and Organization ..................................................................................12 References.................................................................................................................12 3 REVIEW OF INDIVIDUAL SECTIONS................................................................13 Executive Summary..................................................................................................13 Chapter 1: Introduction.............................................................................................17 Chapter 2: Ozone-Depleting Substances ..................................................................20 Chapter 3: Ozone and UV ........................................................................................26 Chapter 4: Ozone Effects on Climate .......................................................................43 Chapter 5: The Future and Recovery........................................................................47 Chapter 6: Implications for the United States...........................................................52 References.................................................................................................................55 APPENDIX A: CCSP SYNTHESIS AND ASSESSMENT PRODUCTS ..............59 APPENDIX B: BIOLOGICAL SKETCHES OF COMMITTEE MEMBERS AND STAFF..............................................................................................60 ix