system
Given the following post, respond as if you're commenting on Reddit:
human
Eli5 why the storms of Jupiter separate gases into striking vortices and bands of heterogenous color, rather than mixing them into a continuous gradient?
gpt
First, there is the phenomenon of Hadley cells. These come about because the planet is round, spinning, and has one side facing the sun. These are pretty stable systems where the wind predominantly flows in a given direction. On Earth, these are responsible for Trade winds (winds strongly blowing west when a little north of the equator, then switch to blowing strongly east above \~30° latitude). On Jupiter, there are a lot more of these cells, each cell is one of the colored bands.

The vorticies that you see are the interactions of these two circulation cells. 

The colors of the clouds come from two chemicals, Ammonia clouds (white) and ammonium hydrosulfide (brown)

On Jupiter, like on Earth, the atmosphere cools at higher altitudes. In the regions of the atmosphere where the air is rising, it reaches an elevation where it is cool enough that the ammonia condenses into clouds. These clouds are heavier than the air around them, but they are held up (and replinished) by the updrafts. In the regions where the air is falling, there is no ammonia to form clouds, and any ammonia clouds that are formed get pushed down to where it is warmer, so they evaporate. As a result, you can see the atmosphere below the ammonia cloud layer, which has a brownish color.

As a side note, Jupiter is big. Those tiny vorticies that you see would be continent-spanning hurricanes if they were on Earth.