GEOG 3 Lecture 4: GEOG - Lect. 4
Document Summary
The general term used to describe the amount of water vapor in the air. Water molecules weigh less than molecules of dry air. Dry air = 0% humidity (more mass per unit area: =higher density & pressure. Moist air = 100% humidity (less mass per unit area: = lower dense & pressure. So, for the same number of molecules, most air weighs less than dry air. The horizontal motion of air across earth"s surface: two main properties: speed and direction, instruments: Winds are named from the direction from which they originate: a northerly wind blows from the north towards the south, a westerly wind blows from the west towards the east. May be expressed in terms of compass points (n, nw, ne ) or in degrees about. Tuesday, october 17, 2017: easterly wind = 90o, southerly = 180o, westerly = 270o, northerly wind = 360o or 0o. The wind direction at sb is southernly.
