Ozone and other trace gases in the Arctic and Antarctic regions: Three-dimensional model simulations

Journal Article · Wed Feb 20 04:00:00 EST 1991 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/90JD01779· OSTI ID:5560738

Granier, C; Brasseur, G ^[1]

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1. National Center for Atmospheric Research, Boulder, CO (USA)

A three-dimensional mechanistic model of the middle atmosphere with calculated dynamics and chemistry is used to study the behavior of chemically active trace gases at high latitudes in winter and spring, and to simulate the formation of an ozone hole in Antarctica. The dynamics of both hemispheres is simulated by applying at the lower boundary of the model (8.5 km) a wavelike perturbation representing qualitatively a climatological tropospheric forcing. The chemical heterogeneous processes converting chlorine reservoirs into active chlorine in cold air masses are parameterized. The model simulates the behavior of nitrogen oxides, nitric acid, water vapor, methane, hydrogen radicals, chlorine compounds, and ozone. It reproduces important features observed during different Antarctic and Arctic observation campaigns. The ozone hole in the southern hemisphere can only be simulated when the heterogeneous polar chemistry is taken into account. The springtime ozone depletion over Antarctica calculated in the model is thus mostly the result of chemical removal although the dynamics is responsible for the low temperature that triggers the large ozone loss rates. Unresolved questions are related to the strength of the vertical exchanges inside the vortex, the preconditioning of trace gases before and during the winter season, the behavior of the different trace gases as the vortex breaks down (dilution effects), accurate determination of the ozone sink inside the vortex, and a better quantitative estimation of the role of polar stratospheric clouds. Despite elevated concentrations of active chlorine at high latitudes in the northern hemisphere in late winter, no ozone hole is produced by the model, even with chlorine levels as high as 6 ppbv. This conclusion could, however, be modified for very stable and cold winters with delayed final warming.

• OSTI ID: 5560738
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 96:D2; ISSN 0148-0227; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540110*
ALKANES
ANTARCTIC REGIONS
ARCTIC REGIONS
ATMOSPHERIC CHEMISTRY
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMISTRY
CHLORINE COMPOUNDS
CLIMATE MODELS
EARTH ATMOSPHERE
ECOLOGICAL CONCENTRATION
FLUIDS
GASES
HALOGEN COMPOUNDS
HOLES
HYDROCARBONS
HYDROGEN COMPOUNDS
INORGANIC ACIDS
LAYERS
MATHEMATICAL MODELS
METHANE
NITRIC ACID
NITROGEN COMPOUNDS
NITROGEN OXIDES
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
OZONE
OZONE LAYER
PHOTOCHEMICAL REACTIONS
POLAR REGIONS
RADICALS
SEASONAL VARIATIONS
STRATOSPHERE
VAPORS
VARIATIONS
VORTICES
WATER VAPOR