The structure of the atmosphere of Jupiter above the troposphere was investigated through the radio occultation experiment as well as by IRIS. The level in which the minimum temperature of about -173° C occurs has a pressure of 0.1 atmosphere. Above this point lies the stratosphere, in which temperatures increase with altitude as a result of sunlight absorbed by the gas or by aerosol particles resembling smog. At 70 kilometers above the ammonia clouds, the temperature is about -113° C. Above this level, the temperature stays approximately constant, although at extreme altitudes the temperature again rises in the ionosphere.
If one could “unwrap” Jupiter like a map, views such as these would be obtained. The comparison between the pictures shows the relative motions of features in Jupiter’s atmosphere. It can be seen, for example, that the Great Red Spot moved westward and the white ovals eastward during the time between the acquisition of these pictures. Regular plume patterns are equidistant around the northern edge of the equator, while a train of small spots moved eastward at approximately latitude 80° S. In addition to these relative motions, significant changes are evident in the recirculating flow east of the Great Red Spot, in the disturbed region west of the Great Red Spot, and as seen in the brightening of material spreading into the equatorial region from the more southerly latitudes. [P-21771C]
The planet as it appeared about March 1.
As it was in early July.
Weather on Jupiter
The Voyager pictures reveal a planet of complex atmospheric motions. Spots chase after each other, meet, whirl around, mingle, and then split up again; filamentary structures curl into spirals that open outward; feathery cloud systems reach out toward neighboring regions; cumulus clouds that look like ostrich plumes may brighten suddenly as they float toward the east; spots stream around the Red Spot or get caught up in its vortical motion—all in an incredible interplay of color, texture, and eastward and westward flows. Such changes can be noticed in the space of only a few Jovian days.
Differing characteristics of Jupiter’s meteorology are apparent in high-resolution images, such as this one taken by Voyager 1 on March 2 at a range of 4 million kilometers. The well-defined pale orange line running from southwest to northeast (north is at the top) marks the high-speed north temperate current with wind speeds of about 120 meters per second. Toward the top of the picture, a weaker jet of approximately 30 meters per second is characterized by wave patterns and cloud features which have been observed to rotate in a clockwise manner at these latitudes of about 35°N. These clouds have been observed to have lifetimes of one to two years. [P-21193C]