The most fundamental reason that Earth has wind is because it is a sphere (basically; it "bulges" slightly at the equator due to its rotation). Differential heating creates the winds, which are then rerouted by Earth's rotation and land-sea boundaries. In turn, winds influence precipitation patterns and indirectly drive ocean currents. This post will walk through the basics. If you don't want to read the whole thing, you can skip to the summary. Read more →