February 28, 2007
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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 4, NUMBER 2, FEBRUARY 1991
GENERAL INTEREST AND COMMENTARY
"Free Radicals within the Antarctic Vortex: The Role of CFCs in the
Antarctic Ozone Loss," J.G. Anderson (Dept. Chem., Harvard Univ., Cambridge
MA 02138), D.W. Toohey, W.H. Brune, Science, 251(4989), 39-46,
Jan. 4, 1991.
Discusses three lines of evidence that define the link between global
release of CFCs to episodic disappearance of ozone from the Antarctic
stratosphere during the austral spring. Recent advances, including improved
absolute calibration for ClO and BrO concentrations as encountered in the lower
Antarctic stratosphere, have been essential for defining the link.
"The Dynamics of the Stratospheric Polar Vortex and Its Relation to
Springtime Ozone Depletions," M.R. Schoeberl (NASA-Goddard, Greenbelt MD
20771), D.L. Hartmann, ibid., 46-53.
Recent aircraft data show that gradients of potential vorticity and
conservative trace species are large at the transition from mid-latitude to
polar air, implying that inward mixing of heat and constituents is strongly
inhibited and that the perturbed polar stratospheric chemistry of the ozone hole
is isolated from the rest of the stratosphere until the vortex breaks up in late
spring. It appears that the Antarctic ozone hole could reach larger dimensions
than so far observed, but the Northern Hemisphere has a smaller theoretical
maximum for column ozone depletion, about 40 percent of that observed in
"Future Changes in Stratospheric Ozone and the Role of Heterogeneous
Chemistry," G.P. Brasseur (NCAR, POB 3000, Boulder CO 80307), C. Granier,
S. Walters, Nature, 348(6302), 626-628, Dec. 13, 1990.
Even if the agreed upon international protocol is followed, reactions on the
surfaces of sulfuric acid aerosol particles could produce significant ozone
depletion into the beginning of the next century, especially if a major volcanic
"The Influence of Solar Forcing Trends on Global Mean Temperature
since 1861," P.M. Kelly (Clim. Res. Unit, Univ. E. Anglia, Norwich NR4 7TJ,
UK), T.M.L. Wigley, ibid., 347(6292), 460-462, Oct. 4, 1990.
Considered the role of long-term solar irradiance changes associated with
sunspot fluctuations. Concluded that compared to the well-established
observational and theoretical basis for the influence of increased greenhouse
forcing, the case for a solar effect on recent changes in global climate is
extremely speculative. (See Research News, this GLOBAL CLIMATE CHANGE DIGEST
"Ecosystem Approach to a Global Nitrous Oxide Budget," P.A.
Matson (NASA-Ames, Moffett Field CA 94035), P.M. Vitousek, BioScience,
40(9), 667-672, Oct. 1990.
Discusses the nitrogen oxide budget for various types of tropical forests as
a function of soil fertility, including the role of elevation and of human
disturbance. The approach examines fluxes of trace gases by considering
gradients of factors that control fluxes and ecosystem properties and processes.
"AGU Planet Earth Committee Report: Implementation," A.M.
Dziewonski (Harvard Univ., Cambridge MA 02138), W.M. Kaula, Eos, 71(51),
1871, Dec. 18, 1990. With some exceptions, plans for new spaceborne systems to
be part of the Mission to Planet Earth are well underway, but the already
launched LANDSAT and GOES systems are not as feasible as they might be.
Interpretation of measurements needs adequate attention because of the vastly
increased volume of data to be generated by systems like EOS. Modeling will
require the use of gifted scientists and state-of-the-art mainframe computers.
"____________: Biosphere Interactions," P. Sellers (Univ.
Maryland, College Pk.), J.J. McCarthy, ibid., 71(52), pp.
1883-1884, Dec. 25, 1990. Reviews ongoing studies relating to the short
time-scale, biophysically-controlled interactions between the land biosphere and
the atmosphere, with some reference to those components of the biota that change
relatively slowly as a result of climate change. To acquire a quantitative
understanding on time scales of hours to years, theories and measurements will
need to reach a high level of realism and precision, with a determined
initiative in modeling and experimentation.
"_____________: The Impact of Man," M.G. Wolman (Johns Hopkins
Univ., Baltimore, Md.), ibid., pp. 1884-1886. Understanding and
predicting the human impact on the Earth requires expanded measurement and
improved modeling. However, the rational response to scientific findings may
require measures of great cost to society, such as shifting from fossil fuel to
other energy sources. Scientists should demand better support for the work
needed to reduce uncertainty, but must give policy makers well considered advice
about the risks involved.
"Memo to U.S. Energy Executives: Don't Forget Global Warming,"
J.A. Howes (Intl. Energy Group, Washington, D.C.), Publ. Util. Fortnightly,
12-13, Dec. 20, 1990. If the world-wide global warming environmental movement
reaches its goal of an international agreement on regulating greenhouse gases, a
new approach may be needed in allocating customer and corporate resources.
"A Sustainable World," E.S. Woolard (Chairman & CEO, DuPont
Corp., 1007 Market St., Wilmington DE 19898), Chem. & Industry, No.
22, 738-740, Nov. 19, 1990. Believes that industry can develop powerful,
purposeful environmental programs without retreating to prehistoric lifestyles,
if corporate managers have the will to do so.
Guide to Publishers
Index of Abbreviations