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The situation is even worse than this, because Jupiter doesn't absorb all of the sunlight that strikes it. This indicates that Jupiter gives off more radiation than it receives from the Sun. Jupiter must have an internal energy source.

The fact that the temperature fall-off with altitude below the clouds is close to the adiabatic rate suggests that convection is an important form of energy transport. (Remember, we saw that, on Earth, when there is a rapid drop in temperature with altitude, then convection can be very strong.) Because of the temperature distribution, we think that there are three major cloud layers, resulting from the fact that different constituents condense at different temperatures and pressures. We think that the highest cloud layer is ammonia ice, the middle layer is ammonium hydrosulfide (NH4SH), in the form of crystals, and the lowest layer is water, in a mixture of liquid and ice.

The varying conditions mean that the chemistry is different at different altitudes. We think that the different cloud colors reflect different compositions, a result of the varying chemistry. The different colors come from different temperature ranges, and therefore from different levels. For example, the blues correspond to the warmest regions, and are therefore closest to the surface. They are probably only seen through holes in the higher layers. Brown, white and red come from progressively lower temperatures, meaning they come from progressively higher levels. We have still not identified all of the compounds responsible for the various colorations. Other factors besides temperature also affect the chemistry. For example, some regions have more lightning than others, and the energy from the lightning can help certain chemical reactions go.

The east-west winds are quite substantial. They flow at about 100 m/s near the equator, and at about 25 m/s at the higher latitudes. The winds flow in alternating east-west and west-east bands. These alternating wind patterns correspond to the alternating color bands. On Jupiter, there are five or six pairs of alternating bands in each hemisphere. For comparison, on Earth, there are only the westward (in the northern hemisphere) trade winds at low latitudes and the eastward jet stream at high latitudes.

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