Compléter
Fill in the Blanks: Global Weather PatternsVersion en ligne
Weather patterns and ocean currents
Global
Weather
Patterns
The
movement
of
air
and
ocean
currents
across
the
Earth's
surface
create
global
weather
patterns
.
The
weather
of
a
particular
area
depends
on
the
movement
of
the
atmosphere
.
This
movement
can
determine
an
area's
temperature
,
air
pressure
,
and
precipitation
.
Solar
Energy
and
Convection
The
Sun
heats
the
Earth
unevenly
.
Only
one
half
of
the
Earth
receives
sunlight
at
a
time
.
Also
,
the
parts
of
the
Earth
where
the
Sun
is
directly
overhead
receive
more
Solar
energy
.
The
tropics
and
the
equator
receive
more
energy
than
the
poles
.
This
is
why
the
poles
are
much
colder
than
the
tropics
.
Differences
in
the
temperatures
of
air
and
water
cause
convection
.
Convection
is
the
mixing
motion
of
liquids
or
gases
that
are
different
temperatures
.
Convection
happens
because
warm
liquids
or
gases
rise
,
while
cool
liquids
and
gases
sink
.
Convection
in
the
atmosphere
causes
wind
,
while
convection
in
the
ocean
causes
currents
.
A
convection
current
will
continually
circulate
gases
or
liquids
past
the
source
of
heat
,
helping
to
even
out
the
overall
temperature
.
Convection
in
the
Atmosphere
When
sunlight
strikes
land
or
water
,
much
of
the
energy
in
the
light
is
changed
to
heat
.
This
causes
the
air
above
the
Earth's
surface
to
heat
up
.
The
hot
air
rises
,
cools
,
and
comes
back
down
,
forming
air
currents
,
as
shown
in
the
image
.
At
the
same
time
,
the
rotation
of
the
Earth
causes
air
masses
to
"
swirl
"
clockwise
in
the
Northern
hemisphere
and
counter
-
clockwise
in
the
Southern
Hemisphere
.
This
creates
that
blow
from
the
east
near
the
equator
.
It
also
causes
prevailing
that
blow
across
the
United
States
.
The
prevailing
westerlies
cause
weather
patterns
in
the
United
States
to
generally
move
from
west
to
east
.
Global
Air
Currents
Between
the
easterlies
and
westerlies
,
high
in
the
atmosphere
,
air
currents
called
jet
streams
are
located
.
A
jet
stream
is
a
quick
-
moving
ribbon
of
air
.
Jet
streams
constantly
change
position
.
Air
masses
and
weather
systems
in
the
path
of
the
jet
streams
are
moved
by
the
quick
-
moving
air
.
The
Northern
and
Southern
Hemispheres
each
have
two
main
jet
streams
?
a
polar
jet
stream
and
a
subtropical
jet
stream
.
In
the
Northern
Hemisphere
,
the
polar
jet
stream
brings
cold
weather
from
the
north
,
and
the
subtropical
jet
stream
brings
warm
weather
from
the
south
.
In
the
winter
,
jet
streams
are
closer
to
the
equator
.
In
the
summer
,
they
are
farther
from
the
equator
.
The
seasonal
north
and
south
movements
of
the
jet
streams'
positions
are
said
to
follow
the
Sun
,
because
the
Sun's
highest
position
in
the
sky
moves
north
and
south
at
the
same
times
.
Currents
:
Convection
in
the
Ocean
Currents
at
the
surface
of
the
ocean
are
affected
by
wind
.
In
general
,
currents
flowing
toward
the
equator
bring
cooler
waters
to
some
regions
,
while
currents
flowing
away
from
the
equator
bring
warmer
waters
to
other
regions
.
These
currents
carry
water
in
large
loops
,
called
gyres
.
The
five
major
gyres
in
the
ocean
are
shown
in
the
image
below
.
The
five
major
ocean
gyres
on
Earth
are
caused
by
the
Sun's
heat
,
global
wind
patterns
,
and
the
rotation
of
the
Earth
.
Red
arrows
show
warm
currents
.
Blue
arrows
show
cool
currents
.
The
movement
of
ocean
currents
can
have
a
cooling
effect
or
a
warming
effect
on
the
regions
near
those
currents
.
For
example
,
the
California
current
helps
the
west
coast
of
the
United
States
stay
cooler
during
the
summer
.
The
Gulf
Stream
,
however
,
carries
warm
water
to
the
North
Atlantic
,
resulting
in
warmer
winters
in
the
British
Isles
.
Oceans
can
have
a
major
effect
on
climate
in
another
way
also
.
Water
absorbs
solar
energy
without
changing
temperature
much
.
This
means
that
ocean
temperature
remains
within
a
small
range
throughout
the
year
,
even
when
the
amount
of
solar
energy
received
is
changing
.
This
explains
why
the
climate
in
coastal
areas
changes
less
with
the
seasons
than
areas
that
are
far
away
from
the
coast
.
&
El
Niño
and
La
Niña
refer
to
short
-
term
changes
from
normal
wind
and
ocean
current
patterns
in
the
tropical
Pacific
Ocean
.
These
changes
interrupt
normal
global
weather
patterns
.
In
normal
conditions
,
the
blow
from
east
to
west
across
the
tropical
Pacific
Ocean
.
This
builds
up
warmer
water
in
the
western
Pacific
and
allows
colder
water
to
rise
in
the
eastern
Pacific
.
In
certain
periods
of
time
,
two
distinct
,
short
-
term
changes
in
this
pattern
occur
.
These
changes
are
called
El
Niño
and
La
Niña
.
In
El
Niño
conditions
,
such
as
the
conditions
shown
at
the
bottom
of
the
image
above
,
trade
winds
do
not
blow
as
heavily
as
normal
in
the
western
and
central
Pacific
Ocean
.
This
prevents
colder
water
from
rising
as
it
normally
does
in
the
eastern
Pacific
,
and
results
in
warmer
ocean
currents
than
normal
.
El
Niño
usually
occurs
every
3
to
7
years
.
El
Niño
interrupts
normal
global
patterns
.
For
example
,
El
Niño
usually
causes
droughts
in
the
western
Pacific
and
heavier
rains
in
the
eastern
Pacific
.
The
southern
Rocky
Mountains
and
the
southeastern
United
States
will
both
have
increased
precipitation
in
the
winter
of
an
El
Niño
year
.
The
upper
Midwest
and
Northeast
U
.
S
.
will
usually
have
a
warmer
than
average
winter
,
but
the
Gulf
Coast
will
tend
to
be
cooler
than
normal
during
the
winter
months
.
In
La
Niña
conditions
,
the
trade
winds
blow
more
heavily
than
normal
,
causing
more
cold
water
to
rise
and
spread
westward
across
the
Pacific
.
Air
and
surface
water
temperatures
in
the
Pacific
Ocean
near
the
equator
are
colder
than
normal
,
and
global
climate
patterns
are
opposite
those
of
El
Niño
conditions
.
|