The standard way to envision this is to imagine yourself at the center of a large carousel and tossing a ball to someone positioned on the edge. By the time the ball gets to the perimeter, the target person has moved on and the ball passes behind him. From his perspective, it looks as if it has curved away from him. That is the Coriolis effect, and it is what gives weather systems their curl and sends hurricanes spinning off like tops. The Coriolis effect is also why naval guns firing artillery shells have to adjust to left or right; a shell fired fifteen miles would otherwise deviate by about a hundred yards and plop harmlessly into the sea.

Considering the practical and psychological importance of the weather to nearly everyone, it's surprising that meteorology didn't really get going as a science until shortly before the turn of the nineteenth century (though the term meteorology itself had been around since 1626, when it was coined by a T. Granger in a book of logic).