Download Global Wind Belts - 7th Grade Science with Ms. Shaw

Adapted from www.ck12.org and
http://www.metoffice.gov.uk/
by Ms. Shaw
 The
horizontal movement of
air caused by differences in
air pressure.
Air moves from
areas of high
pressure to areas of
low pressure.
Convection currents and the
rotation of the Earth cause
global winds.
Coriolis effect - influence of
Earth’s rotation on the winds.
http://www.youtube.com/watch?v=
YBaseCUhB_E&feature=youtu.be
Winds that travel long distances in
steady patterns over several weeks.
 Uneven
heating
between the
equator and the
poles cause the
global winds.
 Each wind belt is
separated by
calm regions.
Trade Winds: Blow from east,
moving from the “horse”
latitudes (300) towards the
equator. They die out as they
Horse Latitude
get closer to the equator.
Westerlies: Blow from the
Equator
west, moving from the “horse”
Horse Latitude
latitudes (300) towards the
poles.
◦ These winds affect the United
States. They move our weather
from California to North Carolina.
Easterlies: Blow from the east,
moving down from the poles.
Horse Latitude
Equator
Horse Latitude
 High
and low pressure regions created
by the 6 atmospheric circulation cells
determine amount of precipitation in
a region.
◦ Rainfall and storms are common in low
pressure regions due to rising air.
◦ Evaporation occurs in dry areas when air
sinks in high pressure areas.
 Local
winds result from air moving
between small low and high pressure
systems.
Ribbons of very strong winds which
move weather systems around
Earth.
 Found 9-16 km above Earth’s
surface, just below the
tropopause, up to 200 mph.
 Form large temperature
differences between two air
masses.
http://www.youtube.com/wa
tch?v=huweohIh_Bw
Watch the video