Publications
1975
Rossow, W. B.; Sagan, C.
Microwave boundary conditions on the atmosphere and clouds of Venus Journal Article
In: Journal of the Atmospheric Sciences, vol. 32, no. 6, pp. 1164-1176., 1975.
Abstract | Links | BibTeX | Tags: PLANETARY ATMOSPHERES
@article{nokey,
title = {Microwave boundary conditions on the atmosphere and clouds of Venus},
author = {W.B. Rossow and C. Sagan},
url = {https://www.williambrossow.com/wp-content/uploads/2022/01/1975_Rossow_ro08200o-1.pdf, Download file},
doi = {10.1175/1520-0469(1975)032%3C1164%3AMBCOTA%3E2.0.CO;2},
year = {1975},
date = {1975-06-01},
urldate = {1975-06-01},
journal = { Journal of the Atmospheric Sciences},
volume = {32},
number = {6},
pages = {1164-1176.},
abstract = {The dielectric properties of H2O and H2SO4 at microwave frequencies have been calculated from the Debye equations. The derived frequency and temperature dependence agrees wed with existing data. The dielectric properties of H2O/H2SO4 mixtures are deduced and, for a well-mixed atmosphere, the structure of H2O and H2O/H2SO4 clouds is calculated. With the COSPAR model atmosphere and the calculated cloud models, the microwave properties of the atmosphere and clouds are determined. The 3.8 cm radar reflectivity of the planet, the Mariner 5 S-band occultation profile, and the passive microwave emission spectrum of the planet together set an upper limit on the mixing ratio by number of H2O of ∼102 in the lower Venus atmosphere, and of H2SO4 of ∼10−5. The polarization value of the real part of the refractive index of the clouds, the spectroscope limits on the abundance of water vapor above the clouds, and the microwave data together set corresponding upper limits on H2O of ∼2 × 10−4 and on H2SO4 of ∼9 × 10−6. Upper limits on the surface density of total cloud constituents and of cloud liquid water are, respectively, ∼0.1 g cm−2 and ∼0.01 g cm−2. The infrared opacities of 90 bars of CO2, together with the derived upper limits to the amounts of water vapor and liquid H2O/H2SO4, may be sufficient to explain the high surface temperatures through the greenhouse effect.},
keywords = {PLANETARY ATMOSPHERES},
pubstate = {published},
tppubtype = {article}
}
The dielectric properties of H2O and H2SO4 at microwave frequencies have been calculated from the Debye equations. The derived frequency and temperature dependence agrees wed with existing data. The dielectric properties of H2O/H2SO4 mixtures are deduced and, for a well-mixed atmosphere, the structure of H2O and H2O/H2SO4 clouds is calculated. With the COSPAR model atmosphere and the calculated cloud models, the microwave properties of the atmosphere and clouds are determined. The 3.8 cm radar reflectivity of the planet, the Mariner 5 S-band occultation profile, and the passive microwave emission spectrum of the planet together set an upper limit on the mixing ratio by number of H2O of ∼102 in the lower Venus atmosphere, and of H2SO4 of ∼10−5. The polarization value of the real part of the refractive index of the clouds, the spectroscope limits on the abundance of water vapor above the clouds, and the microwave data together set corresponding upper limits on H2O of ∼2 × 10−4 and on H2SO4 of ∼9 × 10−6. Upper limits on the surface density of total cloud constituents and of cloud liquid water are, respectively, ∼0.1 g cm−2 and ∼0.01 g cm−2. The infrared opacities of 90 bars of CO2, together with the derived upper limits to the amounts of water vapor and liquid H2O/H2SO4, may be sufficient to explain the high surface temperatures through the greenhouse effect.
