Cells

the Sahara and the Thar are at the same latitude for the same reason.

drag the sun toward the equator and watch the sky sort itself into six wheels

Heat the equator and warm air rises there, then has to come back down somewhere — it cannot just pile up. It descends around 30 degrees north and south, and descending air is dry air, because it warms as it falls and holds whatever moisture it has instead of dropping it. That single fact is why the Sahara, the Thar, the Atacama and the Australian outback all sit on almost the same two lines of latitude despite being on four different continents: not a coincidence, the same falling air.

Concepts: emergence, heat.

An interactive you play with one thumb, on Wundr.