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 8, NUMBER 10, OCTOBER 1995
Two items in J. Geophys. Res., 100(D7), July 20, 1995:
"Formation of Low-Ozone Pockets in the Middle Stratospheric Anticyclone
During Winter," G.L. Manney (Jet Propulsion Lab., 4800 Oak Grove Dr.,
Pasadena CA 91109), L. Froidevaux et al., 13,939-13,950. Observations during
stratospheric warmings show that tongues of ozone-rich air are drawn into the
anticyclone from low latitudes. Several days later, an isolated region of very
low ozone is formed in the anticyclone. Trajectory calculations and comparisons
with passive tracer data confirm that these low-ozone regions observed in the
midstratosphere could not result solely from transport processes.
"Stratospheric Trace Constituents Simulated by a Three-Dimensional
General Circulation Model: Comparison with UARS Data," R.S. Eckman
(NASA-Langley, Hampton VA 23665), W.L. Grose et al., 13,951-13,966. A one-year
simulation using parameterized polar heterogeneous processes and reactions on
sulfate aerosols agrees fairly well with measurements, but with some differences
with respect to the depth and persistence of southern springtime ozone
depletion. Areas of agreement and disagreement suggest the need for a more
detailed representation of sulfate aerosol processes in the model.
Four items in J. Geophys. Res., 100(D6), June 20, 1995:
"Comparisons of Observed Ozone Trends in the Stratosphere Through
Examination of Umkehr and Balloon Ozonesonde Data," A.J. Miller (NOAA/Clim.
Analysis Ctr., Washington DC 20233), G.C. Tiao et al., 11,209-11,217. Compares
the nonseasonal and seasonal trend behavior of ozone profile data from
measurements for 1968-1991. Results confirm the observation of significant
negative ozone trends of about -6% in both the lower stratosphere (15-20 km) and
upper stratosphere (35-50 km), separated by a nodal point in the region of 25-30
"Heterogeneous Conversion of HCl and ClONO2 During the Arctic Winter
1992/1993 Initiating Ozone Depletion," J. Notholt (A. Wegener Inst. Polar &
Meeresforschung, POB 600149, D-14401 Potsdam, Ger.), P. von der Gathen,
11,269-11,274. Measurements in December 1992 showed that almost all HCl and
ClONO2 at 16-22 km had di+sappeared, and therefore the stratosphere was primed
for ozone depletion very early in winter. Results confirm model studies that
indicate that already weak polar stratospheric cloud events can lead to a strong
conversion of chlorine reservoir compounds into active forms, initiating ozone
depletion as soon as sunlight is available.
"Two-Dimensional and Three-Dimensional Model Simulations, Measurements,
and Interpretation of the Influence of the October 1989 Solar Proton Events
[SPEs] on the Middle Atmosphere," C.H. Jackman (Lab. Atmos., NASA-Goddard,
Greenbelt MD 20771), M.C. Cerniglia et al., 11,641-11,660. SPEs have been
associated with significant ozone loss during several periods over the past 20
years. A two-dimensional model, when used to simulate effects of NOx, predicted
lower stratospheric polar ozone decreases of >2% persisting for one and a
half years past these SPEs.
"Descent of Long-Lived Trace Gases in the Winter Polar Vortex,"
J.T. Bacmeister (Naval Res. Lab., Code 7641, Washington DC 20375), M.R.
Schoeberl et al., 11,669-11,684. Observations of CH4 and HF from the Halogen
Limb Occultation Experiment (HALOE) suggest that vigorous descent occurs with
mesospheric values of CH4 evident down to 30 mbar. A highly accurate
two-dimensional model advection scheme, coupled with a modern radiation scheme,
and parameterized planetary and gravity wave drag algorithms, can produce tracer
distributions consistent with HALOE observations.
"The Photoreactivity of Chlorine Dioxide," V. Vaida (Dept.
Chem. & Biochem., Univ. Colorado, Boulder CO 80309), J.D. Simon, Science,
268(5216), 1443-1448, June 9, 1995.
Data from laboratory experiments and quantum calculations reveal details of
the complex chemistry of OClO. Discusses the potential role of this radical in
stratospheric ozone depletion as suggested by the laboratory measurements.
"A Three-Dimensional General Circulation Model with Coupled
Chemistry for the Middle Atmosphere," P.J. Rasch (NCAR, POB 3000, Boulder
CO 80307), B.A. Boville, G.P. Brasseur, J. Geophys. Res., 100(D5),
9041-9071, May 20, 1995.
Documents a new model that includes ozone photochemistry and simulates the
evolution of 24 chemically reactive gases at 44 levels for 3° latitude and 6° longitude. Presents results for a two-year simulation.
Special section: "Stratospheric Ozone Intercomparison
Campaign (STOIC) 1989," J. Geophys. Res., 100(D5), May 20,
". . .Overview," J.J. Margitan (Jet Propulsion Lab., 4800 Oak
Grove Dr., Pasadena CA 91109), R.A. Barnes et al., 9193-9207.
This, and the 11 papers that follow, describe the performance comparison of
new instruments with that of established techniques in a "blind"
experiment. Examination of the data shows excellent agreement among the
techniques, especially in the 20-40 km range.
"Spectroscopic Evidence Against Nitric Acid Trihydrate in Polar
Stratospheric Clouds [PSCs]," O.B. Toon (NASA-Ames, Moffett Field CA
94035), M.A. Tolbert, Nature, 375(6528), 218-221, May 18, 1995.
Reanalyzes infrared spectra of type I PSCs for Antarctica in September 1987.
Finds that the PSCs were not composed of nitric acid trihydrate, but instead had
a more complex composition. Because cloud formation is sensitive to composition,
this finding will alter understanding of the locations and conditions in which
"A Reevaluation of the Ozone Budget with HALOE UARS Data: No
Evidence for the Ozone Deficit," P.J. Crutzen (M. Planck Inst. Chem., POB
3060, 55020 Mainz, Ger.), J.-U. Grooß et al., Science, 268(5211),
705-707, May 5, 1995.
A detailed ozone model budget analysis, under conditions with the strongest
photochemical control of ozone, indicates that an ozone deficit may not exist.
On the contrary, the use of currently recommended photochemical parameters leads
to insufficient ozone destruction in the model.
"Total Ozone Variations in the Arctic During the Winter-Spring
Period," G.P. Gushchin (Main Geophys. Observ., Russia), T.A.
Pavlyuchenkova, Russian Meteor. & Hydrol., No. 9, pp. 35-40, 1993.
Derives ground-based data on total ozone content (TOC) for the territory
northward of 50° N for 1981-1987. No TOC decrease similar to that in the
Antarctic has been observed in the Arctic inside or outside the polar
"The Stratospheric Ozone LayerAn Overview," T. Peter (M.
Planck Inst. Chem., POB 3060, 6500 Mainz, Ger.), Environ. Pollut., 83,
Summarizes dynamic, chemical and microphysical questions, with an emphasis
on chemistry. Discusses chemical reactions which can occur under relatively warm
conditions and which could contribute to the observed mid-latitude ozone
depletion. Dynamic processes are important, and appear to be the main cause of
the anomalously low ozone levels in the Northern Hemisphere during the 1991-1992
Guide to Publishers
Index of Abbreviations