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Pollack, James B.

Publications and source records attributed to Pollack, James B..

74 records · Page 5

Vertical structure of aerosols and clouds in the atmospheres of Uranus and Neptune: Implications for their heat budgets

Models possessing an upper haze layer of finite optical depth and a lower cloud layer of infinite optical depth at discrete altitudes are used to bound the wavelength-averaged phase integrals and bolometric albedos of Uranus and Neptune. The models differ in the assumed value of the particles single scattering phase function and the wavelength dependence of the haze optical depth. A range of phase functions, from the isotropic to those characterizing Titan, Jupiter, and Saturn atmosphere particles, are discussed. The results obtained imply that the meteorological regimes in the observable atmospheres of Uranus and Neptune may differ considerably; internal heat flux could play a much more important role for Neptune than for Uranus.

Pollack, James B.

Reports from Science Mount St. Helens

The following reports describe extensive measurements of the properties of the gases and aerosols (particles) in the volcanic clouds produced by the eruptions of Mount St. Helens from March through August 1980. Volcanic material was first injected into the atmosphere on 27 March 1980. This material, as well as that introduced by subsequent eruptions during the next 2 months, was confined to the troposphere. On 18 May the first of several major explosions occurred in which some of the volcanic cloud penetrated well into the stratosphere. The nature of the volcanic activity at Mount St. Helens from the end of March through June was described.

Pollack, James B.