GEOG 101 Lecture Notes - Lecture 5: Polar Front, Jet Stream, Murchison Promontory
Document Summary
Atmospheric pressure = weight of air in the atmosphere over a given area. Decreases exponentially with altitude: wind is determined by 3 forces. Force that causes air to move from a place of higher pressure to a place of lower pressure. Direction of the pgf is always from high to low. The larger the pgf, the more intense the wind. The apparent deflection of air once it has been set into motion. Deflection is 0 at the equator and strongest at the poles. As air moves from high to low pressure in the northern hemisphere, it is deflected to the right. In the southern hemisphere, air moving from high to low pressure is deflected to the left. Direction of this force is always opposite of the wind direction. Intensity of the force depends on the roughness of the surface: low pressure center, high pressure center, vertical motion, geostrophic balance (pgf and cf only)
