February 28, 2007
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A Guide to Information on Greenhouse Gases and Ozone Depletion
Published July 1988 through June 1999
FROM VOLUME 6, NUMBER 2, FEBRUARY 1993
Three items from Nature, 360(6402), Nov. 26, 1992:
"Keeping the Sun in Proportion," A.A. Lacis (NASA Goddard Inst.
Space Studies, 2880 Broadway, New York NY 10025), B.E. Carlson, p. 297.
Discusses implications of the following two papers, which do not find the sun to
be the major determinant of recent observed warming. Arguments concerning the
solar influence should not distract policy makers from controlling greenhouse
"Solar Cycle Length, Greenhouse Forcing and Global Climate," P.M.
Kelly (Clim. Res. Unit., Univ. E. Anglia, Norwich NR4 7TJ, UK), T.M.L. Wigley,
328-330. Models the effects of a combination of greenhouse and
solar-cycle-length forcing, and compares with observed temperatures. This
forcing combination can explain many features of the recent temperature record,
although results must be interpreted cautiously. Even with optimized solar
forcing, most of the recent warming trend is explained by greenhouse forcing.
"Implications for Global Warming of Intercycle Solar Irradiance
Variations," M.E. Schlesinger (Dept. Atmos. Sci., Univ. Illinois, Urbana IL
61801), N. Ramankutty, 330-333. A simple climate-ocean model provides strong
circumstantial evidence that there have been intercycle variations in solar
irradiance which have contributed to the observed temperature changes since
1856. However, since the nineteenth century, greenhouse gases have had the
dominant influence on temperature changes.
"Atmospheric Lifetimes of Long-Lived Halogenated Species," A.R.
Ravishankara (NOAA, 325 Broadway, Boulder CO 80303), S. Solomon et al., Science,
259(5092), 194-199, Jan. 8, 1993.
The lifetimes of several perfluoro and similar inert compounds, already in
use or being considered as CFC substitutes, were assessed by combining
laboratory observations with a 2-D atmospheric model. The lifetimes of all
studied perfluoro compounds exceed 2,000 years, and those of CF3Cl, CF3CF2Cl and
CF2ClCF2Cl exceed 300 years. The effects of these molecules will persist for
centuries or millennia after their release.
"A Model-Based Approach to the Calculation of Global Warming
Potentials (GWP)," J. Rotmans (Nat. Inst. Public Health & Environ.
Protec., POB 1, 3720 BA Bilthoven, Neth.), M.G.J. Den Elzen, Intl. J.
Climatol., 12(8), 865-874, Dec. 1992.
Calculates GWP values with the integrated climate assessment model IMAGE,
using two different methods, for 16 of the most important greenhouse gases and
eight potential CFC substitutes. Resulting values, which depend on the emission
scenario used, are substantially higher than the IPCC estimates, because the
IMAGE model has a balanced carbon budget. The model yields lower projections of
future atmospheric CO2 compared with the IPCC projections.
"Action Spectrum for DNA Damage in Alfalfa Lowers Predicted Impact
of Ozone Depletion," F.E. Quaite (Biol. Dept., Brookhaven Nat. Lab., Upton
NY 11973), B.M. Sutherland, J.C. Sutherland, Nature, 358(6387),
576-578, Aug. 13, 1992.
Calculations based on a new action spectrum predict significantly smaller
increases in biologically effective UV resulting from ozone depletion,
particularly at high latitudes, than calculations based on the widely used
generalized action spectrum encompassing wavelengths from 280 to 313 nm. (For
discussion of the work by the authors and other scientists, see "Plant
Study Questions Nature of Ozone Risk," New York Times, p. C2, Aug.
Five installments of Geophysics News 1992, a series of concise
research updates appearing in the American Geophysical Union's weekly Eos:
"Including Eddies in Global Ocean Models," A.J. Semtner (Naval
Postgrad. Sch., Monterey CA 93943), R.M. Chervin, p. 59, Feb. 2, 1993.
Successful simulations of the oceanic "conveyor belt" that include
mesoscale eddies signal a new era for climate modeling.
"Do Solar Variations Change Climate?" G.C. Reid (Aeronomy Lab.,
NOAA, 325 Broadway, Boulder CO 80303), p. 23, Jan. 12, 1993. There is mounting
evidence for the Sun's control of our past climate, but human activities are
"Deglaciation Triggered by the Resumption of North Atlantic Deep Water,"
J.D. Wright (Lamont-Doherty Earth Observ., Palisades NY 10964), ibid.,
p. 24. New evidence supports a stronger connection between deep ocean
circulation changes and warming trends.
"A New Perspective on Global Warming," T.R. Karl (NCDC, Fed.
Bldg., 37 Battery Pk. Ave., Asheville NC 28801), ibid., p. 25. Discusses
the recently identified global decrease in diurnal temperature range.
"Harmful UV Radiation May Increase after Volcanic Eruptions," A.M.
Vogelmann (Dept. Meteor., Pennsylvania State Univ., Univ. Pk. PA 16802), T.P.
Ackerman, ibid., p. 25. Anthropogenic emissions have increased ozone
layer sensitivity to volcanic eruptions.
"The Greenhouse Effect," A. Berger (Inst. Astron., Univ.
Catholique de Louvain, B-1348 Louvain-la-Neuve, Belg.), C. Tricot, Surveys
Geophys., 13(6), 523-549, Nov. 1992.
A review of recent findings on the Earth radiation balance and climatic
feedback mechanisms, particularly the role of clouds.
Guide to Publishers
Index of Abbreviations