2101 Constitution Ave., NW Washington, DC 20418

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 National Science Foundation under Grant No. ATM-9814235, U.S. Environmental Protection Agency, National Oceanic and Atmospheric Administration, and National Aeronautics and Space Administration. Any opinions, findings, and conclusions or recommendations expressed are those of the authors and do not necessarily reflect those of the sponsors or their subagencies.

International Standard Book Number 0-309-08256-0

Additional copies of this report are available from:
National Academy Press
2101 Constitution Avenue, NW Lockbox 285 Washington, DC 20055 800–624–6242 202–334–3313 (in the Washington metropolitan area)

Printed in the United States of America

Copyright 2001 by the National Academy of Sciences. All rights reserved.

The National Academies of Sciences, Engineering, and Medicine
500 Fifth St. N.W. | Washington, D.C. 20001

Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement