The Atmosphere - Chapter 3: Factors Affecting Wind Flashcards
What is the horizontal movement that is as important as vertical movement in the atmosphere?
Wind
Air will move vertically if it is warmer (and more buoyant) than surrounding air, but what causes it to move horizontally as wind?
It’s the result of horizontal differences in air pressure
Air flows from areas of ___ pressure to ____ pressure
higher
lower
Wind is nature’s attempt to balance _____
inequalities in air pressure
What is the ultimate driving force of wind (note: because of unequal heating)
Solar radiation
Wind is controlled by these four forces:
Pressure gradient force
Coriolis effect
Friction
Tendency of moving object to continue moving in straight line
What is the name loosely for the tendency of a moving object to continue moving in a straight line
Centrifugal force
Pressure differences create wind, and variations in air pressure are determined from barometric readings using _____, lines that connect places of equal air pressure
isobars
The spacing of isobars indicating the amount of pressure change occurring over a given distance is expressed as….
pressure gradient
Closely spaced isobars indicate a ___ pressure gradient and high winds
Steep
Widely spaced isobars indicate a ___ pressure gradient and light winds
weak
What is the Coriolis effect?
The deviation wherein the wind does not ross the isobars at right angles as the pressure gradient force directs
What are the four rules of the Coriolis Effect?
Always directed at right angles to direction of windflow
Affects only wind direction, not wind speed
Affected by wind speed (stronger wind = stronger deflection)
Strongest at poles and weakens equatorward where it eventually becomes nonexistent
Upper-air winds that blow parallel to the isobars
Geostrophic winds
Due to the lack of friction, geostrophic winds travel at ____ than surface winds
higher speeds
