Atmosphere & Ocean Flashcards
(35 cards)
Wind
motion of air
-named from direction of origin
Prevailing Winds
prominent wind speed/direction in a particular area
Atmospheric Pressure
-force per unit area that is exerted against a surface by air
with altitude, density and pressure….
DECREASE
Low Pressure, Low density air is…
warm and moist
High pressure high density air is…
cool and dry
1 atmosphere =
1013.25 hPa =1013.25 mb = 14.7 psi
What does wind result from?
differences in pressure and density!
Only true vertical force
Gravity
Pressure Gradient Force
-air flows form high pressure area to low pressure area
Coriolis Deflection
- due to Earth being a rotating sphere
- sets objects in straight path in curved line
Friction
- affects surface flow
- opposes direction of motion
- depends on velocity and viscosity
Higher PGF means
Stronger wind
Isobar
a line of equal pressure
-closer spacing, higher PGF, stronger winds
Diverging, Descending
-high pressure area
Ascending Converging
-low pressure area
for ONLY PGF
- wind would move at right angle from isobars
- direction high -> low pressure areas
Cyclone
-ascending and converging
counter clock wise (NH)
Anticyclone
descending and diverging clock wise (NH)
PGF + Coriolis Force creates
- geostrophic winds
- upper tropospher
Primary Circulation is..
general global circulation
Secondary Circulation is…
migrating high and low pressure systems
Tertiary Circulation
- local winds
- temporal weather
Meridian Circulation Flows
-move north or south along meridians
