You'll find lots of clouds over tropical climates and practically no clouds over desert climates. There is heavy rainfall in tropical climates and therefore relatively high rates of evaporation. High rates of evaporation leads to condensation and cloud formation. Desert climates like the Sahara Desert that only receives a few inches of rainfall per year would not have clouds due to the lack of surface water for evaporation.
It is the <span>sinking of one tectonic plate under another. Hope I helped :)</span>
