Still kinda hoping we would see more about the razorgirl from the original trailer. The story that scene and the final scene were telling seemed pretty wild.
Wind is caused by the motion of the earth, convection and to some degree momentum of the air itself. Pressure is a by-product of wind, terrain and gravity.
By and large it's convection forces and the earth's rotation though.
FYI on Civilization 6. Free Cities do NOT turn over after 10 turns. It does another loyalty check and in some cases you might see a Free City stay free indefinitely.
The main difference is that the city gains no bonuses from nearby cities or governors so they are far easier to entice into your own Civ.
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