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 4, NUMBER 10, OCTOBER 1991
"Response of the [NCAR] Community Climate Model to Improvements in
the Representation of Clouds," A. Slingo (NCAR, POB 3000, Boulder CO
80307), J.M. Slingo, J. Geophys. Res., 96(D8), 15,341-15,357,
Aug. 20, 1991.
Inclusion of a new parameterization for the shortwave radiative properties
of water clouds as well as the ECMWF cloud prediction scheme in the NCAR model
led to improvements in model temperature structure, radiation budget and cloud
radiative fluxes, compared to data. Although cloud distributions over the
subtropical oceans appear realistic, results show that a more comprehensive
formulation of the cloud boundary layer is required.
"The Sensitivity of a General Circulation Model Climate to the
Moisture Transport Formulation," P.J. Rasch (addr. immed above), D.L.
Williamson, ibid., 96(D7), 13,123-13,137, July 20, 1991.
Examines two versions of the model which produce very different climatologies,
primarily as a result of the redistribution of water vapor.
"Sensitivity of the Global Climate System to Initial Conditions,"
A.A. Tsonis (Dept. Geosci., Univ. Wisconsin, Milwaukee WI 53201), Eos,
72(30), 313, 328, July 23, 1991. Model experiments altering the initial
conditions of control runs for climate predictions suggest that predictions of
altered climate based on models may not have any merit after about 50 years from
the starting point.
Two articles from: Clim. Dynamics, 6(1), July 1991.
"Multiforced Statistical Assessments of Greenhouse-Gas-Induced Surface
Air Temperature Change 1890-1985," C.-D. Schönwiese (Inst. Meteor.,
J.W. Goethe Univ., Feldbergstr. 47, W-6000 Frankfurt 1, Ger.), U. Stähler,
23-33. Multivariate statistical analysis is applied to data from Hanson and
Lebedeff to remove fluctuations associated with volcanic, solar, ENSO and
anthropogenic greenhouse gas forcing. Deduced trends associated with greenhouse
forcing are very similar to some GCM results indicating maximum CO2 doubling
signals in the Arctic winter, but the signals are moderate in the tropics and
"Meridional Oscillations in an Idealized Ocean-Atmosphere System, Part
I: Uncoupled Modes," V.M. Mehta (Dept. Meteor., Florida State Univ.,
Tallahassee FL 32306), 49-65. Results from a coupled model with two atmospheric
and two oceanic layers show that uncoupled, free modes in the presence of mean
meridional circulations have time scales of a week to several decades in the
atmosphere and two years to several centuries in the ocean.
"The Effect of Snow Cover on the Climate," J. Cohen
(NASA-Goddard, 2880 Broadway, New York NY 10025), D. Rind, J. Clim.,
4(7), 689-706, July 1991. Experiments with the GISS GCM showed that snow
cover caused only a short-term local decrease in the surface temperature;
results emphasize the negative feedback which limits the impact of snow cover
over longer time scales.
"Evidence for Decadal Variability in an Ocean General Circulation
Model: An Advective Mechanism," A.J. Weaver (Dept. Meteor., McGill Univ.,
805 Sherbrooke St. W, Montreal, P.Q. H3A 2K6, Can.), E.S. Sarachik, Atmos.-Ocean,
29(2), 197-231, June 1991. Experiments with the Bryan-Cox Ocean GCM show
decadal oscillations associated with advection of salinity and temperature
anomalies; crucial to their existence is the use of a low eddy viscosity
"Dependence of Cloud Amount on Horizontal Resolution in the [NCAR]
Community Climate Model," J.T. Kiehl (NCAR, POB 3000, Boulder CO 80307),
D.L. Williamson, J. Geophys. Res., 96(D6), 10,955-10,980, June
Total cloud amount decreases monotonically with increased horizontal
resolution, especially in the low-level cloud associated with stable
condensation in the tropics. Results have important implications for cloud
parameterization in large-scale models, and raise questions relating to scale
dependence of cloud and precipitation parameterizations.
"Approaches to the Simulation of Regional Climate Change: A Review,"
F. Giorgi (addr. immed. above), L.O. Mearns, Rev. Geophys., 29(2),
191-216, May 1991. Finds that a modeling approach, in which regional scale
forcings are described by increasing the resolution of a GCM in areas of
interest, holds the most promise compared to more empirically based approaches.
"A Zonal-Averaged Model of the Ocean's Response to Climatic Change,"
S. Rahmstorf (New Zealand Oceanog. Inst., DSIR, Wellington, N.Z.), J.
Geophys. Res., 96(C4), 6951-6963, Apr. 15, 1991.
Describes a new vertical mixing model that combines a
box-advection-diffusion model with a bulk mixed layer model, which simulates
wind mixing and penetrative convection. When subjected to a 3° C warming
for CO2 doubling, the model predicts an ocean temperature rise of
1.5-2.0° C from 1850 to 2050. A scenario for reduced CO2 emissions shows
that the surface warming can be slowed dramatically but that a long-term sea
level rise from thermal expansion may be inevitable.
"Spatial Distribution of Precipitation Seasonality in the United
States," P.L. Finkelstein (Global Process Res., MD-80, US EPA, Res.
Triangle Pk. NC 27711), L.R. Truppi, J. Clim., 4(4), 373-385,
As part of this study, a 90-year climatic record was compared to model
output from four GCMs for both present conditions and for doubled CO2. The
models represent current seasonality reasonably well. For future climate, models
agree somewhat and suggest a trend toward a spring, rather than a summer,
precipitation maximum in the midcontinental areas of the U.S.
"A Comparison of the Climatology of a
Troposphere-Stratosphere-Mesosphere Model with Observations," S. Pawson
(Inst. Meteor., Free Univ. Berlin, D.-Schaefer-Weg 6-10, W-1000 Berlin 41,
Ger.). Describes the performance of an ECMWF GCM, which was extended vertically
to permit investigation of the effects of ozone depletion on radiative-dynamical
"CLASS--A Canadian Land Surface Scheme for GCMs. I. Soil Model,"
D.L. Verseghy (Can. Clim. Ctr., 4905 Dufferin St., Downsview, Ont. M3H 5T4,
Can.), Intl. J. Climatol., 11(2), 111-113, Mar. 1991.
Experiments illustrate the improved model performance using the new scheme,
which incorporates three soil layers with physically based calculations of heat
and moisture transfers at the surface and across the layer boundaries.
Discussion on the causes of climate drift of coupled ocean-atmosphere
models, Beitr. Phys. Atmos., 64(1), 72, Feb. 1991.
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