February 28, 2007
GCRIO Program Overview
Our extensive collection of documents.
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Global Climate Change Digest
A Guide to Information on Greenhouse Gases and Ozone Depletion
Published July 1988 through June 1999
FROM VOLUME 11, NUMBER 3, MARCH 1998
Fluoroform (CHF3, HFC-23) in the Background Atmosphere," D.E. Oram (Sch. Environ.
Sci., Univ. E. Anglia, Norwich NR4 7TJ, UK; e-mail: D.E.Oram@uea.ac.uk), W.T. Sturges et
al.,Geophys. Res. Lett., 25(1), 35-38, Jan. 1, 1998.
Presents the first assessment of this important, unregulated greenhouse gas, which is
increasing in the atmosphere at a rate of 5% per year. It has a long atmospheric lifetime,
and its cumulative emissions through 1995 have a global warming equivalent to 1.6 billion
tons of CO2.
Forcing Due to Tropospheric Ozone and Sulfate Aerosols," R. van Dorland (Royal Neth.
Meteor. Inst., POB 201, 3730 AE De Bilt, Neth.; e-mail: email@example.com), F.J. Dentener,
J. Lelieveld,J. Geophys. Res., 102(D23), 28,079-28,100, Dec. 20, 1997.
Combines a radiative wideband model with calculations of tropospheric ozone and sulfate
aerosols from a 3-D chemistry/transport model, to examine preindustrial (1850),
contemporary, and future (2050) conditions. Global and annual average radiative forcings
approximately balance over the industrial period (1850-1990). The positive radiative
forcing of ozone is expected to increase by another 70% over the period 1990-2050; the
negative forcing of sulfate aerosols is predicted to increase even more (150%). Maximum
changes of both constituents are moving southward in the Northern Hemisphere as a result
of emerging economies.
Radiation and Atmospheric Humidity," J.E. Harries (Blackett Lab., Univ. London,
London SW7 2BZ, UK),Quart. J. Royal Meteor. Soc., 123(544), 2173-2186, Oct.
1997 Part B.
Evaluates two satellite humidity data sets (HALOE and TOVS) and compares with GCM
simulations. Shows that uncertainties of only a few percent in the humidity distribution
could produce changes in the outgoing spectrum of magnitude similar to that caused by a
doubling CO2. Errors in the water vapor amounts generated in model simulations
of climate could therefore be significant.
Change in Climate Parameters with Zero Net Radiative Forcing," A. Sinha (Blackett
Lab., Univ. London, London SW7 2BZ, UK; e-mail: firstname.lastname@example.org), J.E. Harries,Geophys.
Res. Lett., 24(19), 2355-2358, Oct. 1, 1997.
Calculations show that even when simultaneous aerosol and CO2 perturbations
cancel and net radiative forcing is zero, heating rates within the atmosphere and surface
radiation characteristics may still be substantially altered. In view of the effect of
radiative heating on atmospheric motions, and the dependence of biological systems on
insolation, the effects of climate change need to be quantified even when the mean
radiative forcing at all locations is unchanged.
Global Solar Radiation with Increased Horizontal Visibility in Germany Between 1964 and
1990," B.G. Liepert (Lamont-Doherty Earth Observ., Rte. 9W, Palisades NY 10964;
e-mail: email@example.com), G.J. Kukla,J. Clim., 10(9), 2391-2401,
Global solar radiation at all sky conditions throughout much of the diurnal insolation
cycle declined at all stations except one. Results are believed to be reasonably
representative of rural, industrial and urban environments of Europe.
Forcing of Climate Change by CFC-11 and Possible CFC Replacements," N. Christidis
(Dept. Meteor., Univ. Reading, Reading RG6 6BB, UK; e-mail: N.Christidis@reading.ac.uk),
M.D. Hurley et al.,J. Geophys. Res., 102(D16), 19,597-19,609, Aug. 27, 1997.
Calculations indicate a value of radiative forcing for CFC-11 that is 30% higher than
the value adopted by the IPCC, and is believed to be accurate to within 10%.
Forcing Calculations for CH3Cl and CH3Br," A.S. Grossman (Atmos. Sci., Livermore
Natl. Lab., L-103, Livermore CA 94550; e-mail: firstname.lastname@example.org), K.E. Grant et al.,J.
Geophys. Res., 102(D12), 13,651-13,656, June 27, 1997.
Calculations indicate that methyl chloride and methyl bromide have direct global
warming potentials similar to that of methane, but current emission rates are too low to
contribute meaningfully to atmospheric greenhouse warming.
the Meridionally and Seasonally Varying Climate Response Caused by Changes in Ozone
Concentration," R. Bintanja (Inst. Marine Res., POB 80005, 3508 TA Utrecht, Neth;
e-mail: email@example.com), J.P.F. Fortuin, H. Kelder,J. Clim., 10(6),
1288-1311, June 1997.
Experiments with a simplified climate model show that the net effect of tropospheric
ozone increases and stratospheric ozone depletion is a slight global average cooling
(0.001 to 0.003 K per year), which offsets by about 10% the projected surface warming due
to increases in the other greenhouse gases.
Forcing and Temperature Trends from Stratospheric Ozone Changes," P.M. de F. Forster
(Dept. Meteor., Univ. Reading, Reading RG6 6BB, UK; e-mail: firstname.lastname@example.org), K.P.
Shine,J. Geophys. Res., 102(D9), 10,841-10,855, May 20, 1997.
Uses sophisticated radiative transfer schemes and new estimates of ozone trends to
update estimates of stratospheric ozone radiative forcing. The stratospheric ozone changes
may have offset about 30% of the forcing due to increases in well-mixed greenhouse gases
since 1979, and about 15% of the forcing since 1964, at least on a global and annual mean.
of the Climatic Effects of Stratospheric Ozone Losses during the 1980s," R.M. MacKay
(Clark College, Vancouver WA 98663), M.K.W. Ko et al.,J. Clim., 10(4),
774-788, Apr. 1997.
Calculations with a high spatial resolution, seasonal, radiative-dynamical model show
that changes in stratospheric ozone between 1979 and 1990 lowered greenhouse warming by
about 39%. This estimate is higher than the 28% compensation previously estimated using a
lower resolution model.
Forcing of the Earth's Climate System Due to Tropical Tropospheric Ozone Production,"
R.W. Portmann (NOAA-ARL, R/E/AL8, 325 S. Broadway, Boulder CO 80303; e-mail:
email@example.com), S. Solomon et al.,J. Geophys. Res., 102(D8),
9409-9417, Apr. 27, 1997.
Uses several methods to conclude that widespread radiative forcing of at least 0.5 to 1
W m-2 exists over large areas of the tropics for much of the year. This forcing is
comparable in magnitude but opposite in sign to estimates of aerosol forcing from tropical
biomass burning, but the burning contribution to ozone affects a larger area. Effects of
tropical ozone changes could be significant for evaluation of both regional and global
anthropogenic forcing of climate.
Forcing and Climate Response," J. Hansen (NASA Goddard Inst. Space Studies, 2880
Broadway, New York NY 10025; e-mail: firstname.lastname@example.org), M. Sato, R. Ruedy,J.
Geophys. Res., 102(D6), 6831-6864, Mar. 27, 1997.
Examines the sensitivity of a climate model to a wide range of radiative forcings. In
general, the global mean temperature change can vary by 50% or more depending on the
characteristics of the forcing other than its magnitude, such as altitude or time of day.
Nevertheless, results reaffirm the value of the radiative forcing concept for predicting
climate response and comparing different forcings. Halogen-driven ozone depletion may have
offset more than half the radiative forcing since 1979 due to well-mixed greenhouse gases.
Annual Global Mean Energy Budget," J.T. Kiehl (NCAR, POB 3000, Boulder CO 80307;
e-mail: email@example.com), K.E. Trenberth,Bull. Amer. Meteor. Soc., 78(2),
197-208, Feb. 1997.
A review and synthesis that offers a new estimate of the energy budget. Emphasizes the
uncertainties and issues involved in determining the numbers, in order to focus attention
on the need for improvements that will lead to strong, observationally-based constraints
for global climate models.
Guide to Publishers
Index of Abbreviations