February 28, 2007
GCRIO Program Overview
Our extensive collection of documents.
Archives of the
Global Climate Change Digest
A Guide to Information on Greenhouse Gases and Ozone Depletion
Published July 1988 through June 1999
FROM VOLUME 2, NUMBER 11, NOVEMBER 1989
"Scandinavian, Siberian, and Arctic Ocean Glaciation: Effect of
Holocene Atmospheric CO2 Variations," D.R. Lindstrom (Dept. Geol. Sci., POB
4348, Univ. Ill., Chicago IL 60680), D.R. MacAyeal, Science, 245(4918),
628-631, Aug. 11, 1989.
Uses a computer model of coupled ice-sheet shelf behavior to evaluate
whether observed changes in atmospheric CO2 concentrations could have caused the
advance and retreat of Pleistocene ice sheets in the Eurasian Arctic. In
simulations, climatic warming associated with the Holocene rise of atmospheric
CO2 was sufficient to collapse the widespread glaciation and restore present-day
"Diurnally Varying Regional Climatic Simulations," B.G. Hunt
(CSIRO Div. Atmos. Res., Private Bag No. 1, Mordialloc, Vic. 3195, Australia),
H.B. Gordon, Intl. J. Climatol., 9(4), 331-356, July-Aug. 1989.
Assesses a general circulation model's performance simulating diurnal and
interdiurnal variability. Identifies critical features which should be monitored
in climatic-change experiments. The unique diurnal variations simulated at
individual geographical points suggest that systematic distortions must occur in
most near-surface processes in non-diurnal models. The interdiurnal variability
of the model is illustrated by a number of examples, one of which highlights the
potential misrepresentation of air-sea exchanges in models employing fixed
"Simulated Global Distribution and Deposition of Reactive Nitrogen
Emitted by Fossil Fuel Combustion," H. Levy II (Geophys. Fluid
Dynamics/NOAA, POB 308, Princeton Univ., Princeton NJ 08542), W.J. Moxim, Tellus,
41B(3), 256-271, July 1989.
Nitrogen oxides play a major role in the global reactivity of the
troposphere and, in turn, control the levels of a number of greenhouse gases
that influence the global environment. This study uses the medium resolution
GFDL general circulation transport model to simulate the global spread and
deposition of reactive nitrogen. Identifies a number of important source regions
and long-range transport mechanisms. Suggests a major role for either
stratospheric injection or an upper tropospheric source.
"A Stochastic Lagrangian Atmospheric Transport Model to Determine
Global CO2 Sources and Sinks--A Preliminary Discussion," J.A.
Taylor (Coop. Inst. Res. Environ. Sci., CB 449, Univ. Colorado, Boulder CO
80309), ibid., 272-285.
Model estimates of the yearly averaged latitudinal gradient of CO2
concentration match the observed CO2 observations (obtained from the National
Oceanic and Atmospheric Administration Geophysical Monitoring for Climatic
Change (GMCC) program), except over the southern oceans. A biospheric growing
season net flux of 6.5 Gt C was found from model simulations,which explains the
observed seasonal cycle in CO2 concentrations. Suggests further study of the
intensity of the biospheric fluxes above 60<198>N, oceanic fluxes below 45<198>S
and model vertical transport.
"Design and Critical Appraisal of an Accelerated Integration
Procedure for Atmospheric GCM/Mixed-Layer Ocean Models," M.E. Schlesinger
(Dept. Atmos. Sci., Strand Agric. Hall 326, Oregon State Univ., Corvallis OR
97331), Z.-C. Zhao, D. Vickers, J. Clim., 2(7), 641-655, July
The accelerated integration procedure (AIP) attained the equilibrium
climates in these simulations with the computer-time equivalent of about 2.5
unaccelerated solar cycles (years) but, after the switch from the AIP to the
unaccelerated normal integration procedure (NIP), the temperatures increased to
new equilibrium values. Found that the increase in the amplitude of the annual
cycle of atmospheric temperature from the AIP to the NIP, acting through the
ice-albedo/temperature feedback mechanism, causes the change in the equilibrium
climate following the AIP/NIP switch. Suggests caution in using the AIP.
"The Dynamic Greenhouse: Feedback Processes that May Influence
Future Concentrations of Atmospheric Trace Gases and Climatic Change," D.A.
Lashof (U.S. EPA, Washington DC 20460), Clim. Change, 14(3),
213-242, June 1989.
Assesses the relative importance of a wide range of feedbacks by estimating
the gain associated with each individual process. The gain from biogeochemical
feedbacks is estimated to be 0.05-0.29, compared to 0.17-0.77 for geophysical
climate feedbacks. While each of the biogeochemical feedbacks is modest compared
to the vapor feedback, the biogeochemical feedbacks in combination have the
potential to substantially increase the climate change associated with any given
"The Role of Cloud Microphysical Processes in Climate: An Assessment
From a One-Dimensional Perspective," K.-N. Liou (Dept. Meteor., Univ. Utah,
Salt Lake City UT 84112), S.-C. Ou, J. Geophys. Res., 94(D6),
8599-8607, June 20, 1989.
Hypothesizes that there are uncertainties in cloud microphysical processes,
and that a possible key to climate stability due to external radiative
perturbations is the availability of larger or smaller cloud droplets. Smaller
cloud droplets may be produced by additional condensation nuclei over the oceans
as a result of greenhouse warming and pollution over land. Larger cloud droplets
could be caused by the removal of cloud-forming nuclei, resulting from enhanced
precipitation due to greenhouse perturbations. It is critically important to
have a global climatology of the cloud particle radii for various cloud types in
the investigation of the role of clouds in climate.
"Modeling Climate Change: An Assessment of Sea Ice and Surface
Albedo Feedbacks," W.J. Ingram (Dynamical Climatol. Br., Met O 20, United
Kingdom Meteor. Off., Bracknell, Berkshire RG12 2SZ, UK), C.A. Wilson, J.F.B.
Mitchell, ibid., 94(D6), 8609-8622, June 20, 1989.
The net strength of these feedbacks in simulations of climate change has
been estimated for GCMs using a variety of methods; several are applied in a
single CO2-doubling experiment with the U.K. Meteorological Office GCM.
Different methods give values differing by up to a factor of 2 and are shown to
be estimating different quantities. Results emphasize the importance of clouds,
both in shielding surface albedo changes and so reducing their effect, and in
contributing directly to planetary albedo changes. Concludes that care is needed
in quantifying these feedbacks and that previously published numbers are not all
"Climate Sensitivity Due to Increased CO2: Experiments with a
Coupled Atmosphere and Ocean General Circulation Model," W.M. Washington
(NCAR, Boulder CO 80307), G.A. Meehl, Clim. Dynam., 4(1), 1-38,
Three simulations were run on the coupled model: (1) instantaneous doubling
of CO2 (from 330 to 660 ppm), (2) CO2 increasing linearly at a rate of 1% per
year starting at 330 ppm, and (3) CO2 held constant at 330 ppm. Results at the
end of 30 years of simulation showed a globally averaged surface air temperature
increase of 1.6<198>C for the instantaneous doubling and 0.7<198>C
for the transient forcing case. Found that geographical plots of surface air
temperature change in the transient case show patterns of regional climate
anomalies that differ from those in the instantaneous doubling case,
particularly in the North Atlantic and northern European regions. Suggests that
differences in CO2 forcing in the climate system are important in determining
response to CO2 change and time-dependent climate anomalies.
"Seasonal Climatic Changes Induced by Doubled CO2 as Simulated by
the OSU Atmospheric GCM/Mixed-Layer Ocean Model," M.E. Schlesinger (Dept.
Atmos. Sci., Oregon State Univ., Corvallis OR 97331), Z.-C. Zhao, J. Clim.,
2(5), 459-495, May 1989.
Simulations with CO2 concentrations of 326 ppmv (1xCO2) and 625 ppmv (2xCO2)
were performed using an accelerated procedure for 45 solar cycles (years),
followed by the normal unaccelerated integration procedure for 24 and 16 solar
cycles, respectively. In comparison with CO2-doubling simulations by other
models, the OSU model simulates an annual and global mean surface air
temperature warming of 2.8<198>C compared to 3.5-5.2<198>C, and an
increase in the global-mean precipitation rate of 7.8% compared to 7.1-11.0%.
The OSU model also simulates a dessication of the Northern Hemisphere continents
almost everywhere in summer. This is in agreement with other models except the
NCAR model results.
"Analysis of Polar Clouds from Satellite Imagery Using Pattern
Recognition and a Statistical Cloud Analysis Scheme," E.E. Ebert (Bureau
Meteor., GPO Box 1289K, Melbourne, Vic. 3001, Australia), J. Appl. Meteor.,
28(5), 382-399, May 1989.
Combines a pattern recognition algorithm with a hybrid histogram-spatial
coherence scheme to derive cloud classification and fractional coverage, surface
and cloud visible albedos, and infrared brightness temperatures from
multispectral AVHRR satellite imagery. An important result is that the prior
classification of a sample may significantly improve the accuracy of the
analysis of cloud fraction, albedos and brightness temperatures over that of an
unclassified sample. The automated classification and analysis for a set of
AVHRR imagery from the summertime Arctic is in good agreement with manual
interpretation of the satellite imagery.
"A County-Level Approach to Regional Resource Analysis Based on
Climatic Simulation," S.L. Schuhardt, R.M. Cushman (Carbon Dioxide Info.
Anal. & Res. Prog., Oak Ridge Nat Lab., Oak Ridge TN 37831), T.A. Boden,
J. Clim., 2(2), 113 ff., Feb. 1989.
Uses two simple approaches to demonstrate the effects on the production of
soybeans of a possible climate change due to a doubling of atmospheric CO2. The
first approach assumes that future yields will be determined by current
climate-yield relationships; the second uses a multiple regression equation that
relates yield to simulated June and August temperature and July, August, and
September-June precipitation. These two simple analyses show that soybean yields
might decline in areas where the crop is now grown but could expand northwards
and eastwards, and that it is possible to perform analyses of climate change
effects using county-level data combined with additional information.
"Modeling the Trends of the Variability Characteristics of the
Thermodynamic Conditions of the Earth's Climatic System," A.A. Arskii
(Inst. Atmos. Phys., Acad. Sci., Moscow 109017, USSR), I.I. Mokhov, V.K.
Petukhov, Izvestiya, Atmos. and Ocean Phys., 25, 3-13, Jan.
1989. In Russian.
Uses a stochastic energy balance model to study the hemispheric surface
temperature, equator-to-pole temperature difference and ice-snow cover as a
function of the temperature variability trends of the earth's climate system.
Examines the dependence of the trends on random-force parameterization and on
the heat capacity of the system. Shows that the variance of the meridional
gradient of the surface temperature tends to increase in the case of hemispheric
Guide to Publishers
Index of Abbreviations