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Temperature contrasts between warm tropics and cool high latitudes depends on how efficiently heat is transported by the atmosphere (and oceans) from the tropics. This heat transport is generally assumed to be proportional to atmospheric pressure, but we show with a simple model that this prediction fails by orders of magnitude for Mars and Titan. However,(More)
[1] The long-term mean properties of the global climate system and those of turbulent fluid systems are reviewed from a thermodynamic viewpoint. Two general expressions are derived for a rate of entropy production due to thermal and viscous dissipation (turbulent dissipation) in a fluid system. It is shown with these expressions that maximum entropy(More)
and Lemmon 1993) indicated that it may be possible to resolve surface features. An earlier set of WF/PC images We present for the first time relative albedo maps of Titan’s surface. The maps were made from images taken by the Hubble by Caldwell et al. (1992) measured the atmosphere’s north– Space Telescope’s planetary camera (295 km per pixel) through south(More)
The likely scientific questions posed by Titan after the upcoming Cassini mission, and the engineering issues associated with the platforms required for these investigations, are reviewed. Landers and balloons satisfy a limited set of scientific objectives; aeroplanes seem largely impractical due to high power requirements or structural challenges. Airships(More)
We observed Titan with the Hubble Space Telescope in November 2000 using the Wide-Field Planetary Camera (WFPC2) and the Space Telescope Imaging Spectrograph (STIS). Considerable change is apparent between these and observations in 1994-1997 : in particular the North-South asymmetry at visible wavelengths has reversed, with the southern hemisphere brighter,(More)
Dust devil diameters, like many features in nature, have skewed distributions. I summarize, and present in a unified manner, literature values of dust devil optical diameters from seven terrestrial surveys, three rover-based surveys on Mars and two orbital surveys on Mars. The problems of appropriately treating these data are analogous to those for impact(More)
Tomasko and Smith (1982). Examination of the Voyager 2 (V2) data in Smith et al. (1982) reported no significant New measurements of Titan’s hemispheric brightness asymvariation from V1 to V2, consistent with a seasonally varymetry from HST images from 260 to 1040 nm show that the contrast is strongest near 450 nm (blue) and, with the opposite ing asymmetry(More)
wavelength dependence was investigated. Using a high We measured the location, size, and shape of Titan’s shadow in five images taken with the Hubble Space Telescope in 1995. phase-angle image in the clear filter (480 nm) from Voyager We inferred the altitude of Titan’s optical limb at wavelengths 2, Rages and Pollack (1983) found the altitude of the optiof(More)
considered as a pure rock–ice mixture (see Lorenz and Lunine 1997 for a discussion). It is possible that organic compounds (both liquid and I report preliminary measurements of the complex permittivsolid) are present on Titan’s surface—these may allow it to appear optiity of frozen aqueous ammonia solutions at liquid nitrogen cally bright yet defeat the(More)
Degradation of energy to lower temperatures and the associated production of entropy is a general direction for Earth system processes, ranging from the planetary energy balance, to the global hydrological cycle and the cycling of carbon by Earth’s biosphere. This chapter introduces the application of nonequilibrium thermodynamics to the planetary energy(More)