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Page ii
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 Oceanic
and Atmospheric Administration under Contract No. 50-DKNA-7-90052
and by Alcoa. 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 NOAA or
any of its sub-agencies or of Alcoa.
International Standard Book Number 0-309-06891-6
Additional copies of this report are available from:
National Academy Press
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Box 285
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www.nap.edu
Cover: Surface and lower to mid-tropospheric temperature
trends for the period 1979–1998. The surface data (left
panel) are comprised of surface air temperature over land and the
temperature of water at the ocean's surface, and have been
subjected to a slight additional smoothing to simplify the pattern
(Jones et al., 1999). The lower to mid-tropospheric data (right
panel) are derived from satellite observations from the Microwave
Sounding Unit Channel 2 (the so-called "MSU 2LT") (Christy et al.,
2000). For both datasets, the trends are computed using the method
of ordinary least squares. The color key is the same as in Figure
6.2. The map views on the front cover are centered at 30° N and
110° W and the views on the back cover are centered at 30°
S and 70° E. For the globe as a whole (see Figures 6.2 and 7.1
inside), warming has been prevalent at the earth's surface, but
much less so in the lower to mid-troposphere.
Copyright 2000 by the National Academy of Sciences. All rights
reserved.
Printed in the United States of America
First Printing, January 2000
Second Printing, February 2000break