<P> The atmosphere of Jupiter lacks a clear lower boundary and gradually transitions into the liquid interior of the planet . From lowest to highest , the atmospheric layers are the troposphere , stratosphere , thermosphere and exosphere . Each layer has characteristic temperature gradients . The lowest layer , the troposphere , has a complicated system of clouds and hazes , comprising layers of ammonia , ammonium hydrosulfide and water . The upper ammonia clouds visible at Jupiter 's surface are organized in a dozen zonal bands parallel to the equator and are bounded by powerful zonal atmospheric flows ( winds ) known as jets . The bands alternate in color : the dark bands are called belts , while light ones are called zones . Zones , which are colder than belts , correspond to upwellings , while belts mark descending gas . The zones ' lighter color is believed to result from ammonia ice ; what gives the belts their darker colors is uncertain . The origins of the banded structure and jets are not well understood , though a `` shallow model '' and a `` deep model '' exist . </P>
<P> The atmosphere of Jupiter lacks a clear lower boundary and gradually transitions into the liquid interior of the planet . From lowest to highest , the atmospheric layers are the troposphere , stratosphere , thermosphere and exosphere . Each layer has characteristic temperature gradients . The lowest layer , the troposphere , has a complicated system of clouds and hazes , comprising layers of ammonia , ammonium hydrosulfide and water . The upper ammonia clouds visible at Jupiter 's surface are organized in a dozen zonal bands parallel to the equator and are bounded by powerful zonal atmospheric flows ( winds ) known as jets . The bands alternate in color : the dark bands are called belts , while light ones are called zones . Zones , which are colder than belts , correspond to upwellings , while belts mark descending gas . The zones ' lighter color is believed to result from ammonia ice ; what gives the belts their darker colors is uncertain . The origins of the banded structure and jets are not well understood , though a `` shallow model '' and a `` deep model '' exist . </P>
what are the alternating dark and light bands in jupiter 's atmosphere called
what are the alternating dark and light bands in jupiter 's atmosphere called
belts zones
belts zones