system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How does weather work? Where do weather fronts come from and why do they interact the way they do? Do storms only happen when two fronts meet? What the heck even is a weather front?!
gpt
The sun heats up half the Earth while the other half cools. This creates pressure differences in the air. Furthermore, the rotation of the Earth itself causes large cyclic currents of air. Combine these, and air is moving all over the Earth. Different temperatures result in different amounts of water being absorbed or condensed, affecting humidity and causing precipitation.