Have you been in a desert at night? It gets cold, fast. Have you ever dug a few inches down into sand and touched it? It’s much colder than the blazing surface in the summer. Deserts to not typically have dirt, they have sand. Black panels shading a typically black roof will of course decouple the heating from the building. Black panels shading a very pale, very reflective, very insulative ground material is going to absorb and retain more heat