Saturday, October 18, 2008

GCR reduction in the concentration of ozone

Changes to the radiative windows of incoming and outgoing radiation are well described in the literature but seemed to have been "overlooked" by the proponents of AGW.

OZONE plays a very important part in atmospheric radiative transfer. The absorption of the solar ultraviolet radiation by ozone is the dominant heating mechanism in the stratosphere. At thermal infrared wavelengths the main ozone contribution comes from the 9.6 µm band. Clark et al. 1 were unclear, however, whether the supernovae removal of ozone from the atmosphere of the Earth would heat or cool the surface of the planet. There is evidence, reported here, which enables a more precise statement to be made of the effect upon the global Earth. The reduction in the concentration of ozone will cool the stratosphere, troposphere and surface layers of the Earth.

Sensitivity of Surface Temperature and Atmospheric Temperature to Perturbations in the Stratospheric Concentration of Ozone and Nitrogen Dioxide

V. Ramanathan, L.B. Callis, and R.E. Boughner

Journal of the Atmospheric Sciences

Article: pp. 1092–1112

The present paper examines, with the aid of a radiative-convective model, the sensitivity of the globally-averaged surface temperature and atmospheric temperature to perturbations in the concentration of O3 and NO2 within the stratosphere. The analysis considers reductions in stratospheric O3 with and without a simultaneous increase in the stratospheric concentration of NO2. Ozone is reduced uniformly in a region between 12 and 40 km within the stratosphere. The ratio of the percentage change in NO2 to the percentage change in O3 is denoted by δ; three values of δ (0, −6 and −10) are considered.
For all the cases considered, it is shown that reducing stratosphere O3 cools the atmosphere and the surface. If the reduction in O3 is accompanied by a simultaneous increase in NO2, the increase in solar absorption by NO2 partially compensates for the reduction in solar absorption due to a decrease in stratospheric O3. Consequently, the decrease in atmospheric and surface temperatures is smaller for larger values of −δ. The results for the surface temperature changes depend on the adopted cloud model. The change in the surface temperature for the constant cloud-top temperature model is 1.6 times larger than that for the constant cloud-top altitude model.

The model also indicates that the surface temperature is sensitive to the vertical distribution of O3 within the atmosphere. Increasing (or decreasing) the altitude at which O3 density is maximum has a cooling (or warming) effect an the surface temperature. The consequences of O3 reduction to the latitudinal energy distribution are also discussed.

The results should be considered as reflecting the sensitivity of the present model rather than the sensitivity of the actual earth-atmosphere system. However, the present results should be indicative of the potential environmental consequences due to perturbations in the stratospheric concentrations of O3 and NO2


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