Water vapor, tropospheric distribution

Water vapor is distributed throughout the lower troposphere, at highly variable levels. The water vapor content of the atmosphere can be expressed in a variety of ways ... 

The distribution of water vapor in the troposphere is controlled by general climatic conditions rather than by atmospheric photochemistry. On the basis of rainfall measurements, Junge (128) estimated a 10-day average residence time for water vapor. 

We do not measure water vapor directly in the stratosphere. Again we can possibly infer it from the hydrate ion distribution, but this is more difficult because here you have to rely on a thermodynamic equilibrium distribution, which can be altered due to the electric field. Therefore we feel that this method is not very useful because there exist better methods for measuring water vapor. Therefore I simply cannot argue the question. There are no parallel water vapor measurements. As far as the troposphere is concerned, the dew point is measured on the earth in parallel to the nitric acid measurements. But here, as you have seen, we have only so far obtained four data points and that would be premature to discuss anything. 

From the standpoint of regional tropospheric chemistry—which involves near-surface abundances of ozone, wet and dry deposition of acidic species, and transport and lifetimes of trace atmospheric constituents—the climate variables of interest include the variability of distributions of temperature, precipitation, clouds, and boundary-layer meteorology. In the global sense, these variables are controlled by surface and atmospheric temperature and water content. The distributions of temperature and water vapor are in turn controlled by solar and longwave radiation transfer involving the surface and the atmosphere. 

In order to interpret Eq. (16), it is desirable to determine the relationship of r with the height variable z. For the Earth s troposphere, the dominant absorber is water vapor, for which the density distribution is approximately exponential with an absorber scale height Ha of 2 km. The frequency-integrated optical depth is then given by r = where z is expressed in kilometers above the... 

The column density of water in the troposphere is determined largely by the vertical distribution of the vapor. Liquid droplets and ice crystals represent only a minor fraction of the total abundance of H20. Even in dense clouds the mass of water in the vapor phase predominates over that... 

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