Transcript Winds- air currents caused by sun heating the Earth.

Winds1) air currents caused by sun
heating the Earth.
2) Also caused by Pressure
differences on Earth
Winds are named for where they come
from.
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Polar-cold air from polar regions
Temperate/tropic-warm air from near equator
Marine- wet air from oceans
Continental- Dry air from land
Easterlies –winds from the east
Westerlies –winds from the west
(and many more)
Global Wind Movements
POLAR EASTERLIES
Westerlies
NE TRADE WINDS
EQUATOR
Doldrums –no wind
SE TRADE WINDS
Westerlies
POLAR EASTERLIES
Global Winds
1) Polar Easterlies- cold winds move FROM east.
1) They occur between Latitudes 60 & 90 (N & S)
2) Westerlies- warmer winds move FROM west.
1) Between Latitudes 30 & 60 (N&S)
3) NE tradewinds- Hot/wet winds from
Northeast.
1) Between Latitudes 0 & 30 N (North)
4) DOLDRUMS- NO wind/air movement
They occur AT Latitude 0 (equator).
5) SE trade winds- Hot/wet winds from
Southeast
They occur between latitudes 0 & 30 South.
***NOTE: Latitudes 30 N & S are called
‘Horse Latitudes’
Air Masses – moving air with
similar temperature, pressure,
humidity
Air Masses
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cP : Continental Polar = Dry, Cold
mP: Marine Polar = Wet, Cold (snow)
cT: Continental Temperate = Dry, Warm
mT: Marine Temperate = Wet, Warm
(rain)
The Jet Stream- high speed winds
that are 10km above ground that
moves weather WEST to EAST
Wind Movements – Air currents
generally move west to east in a JET
STREAM (The main path of weather)
Coriolis- Rotation of Earth causes
winds to deflect (change direction)
1) To the RIGHT
in the
Northern
Hemisphere
2) To the LEFT in
the Southern
Hemisphere
Coriolis Effect
Local Winds, caused by temp.
differences between Land & Sea.
Land Breeze - Wind from
Land (Night time)
Sea Breeze- wind from sea
Day time
Measuring Wind
• Anemometermeasures Speed
of wind/Air
currents
• The faster it spins,
the faster the wind
speed.
• Can also show
direction.---
Wind Chill-The temperature it feels
like when the wind blows fast.
Wind Energy- Using wind to
produce electricity/heat/energy.
• Positive reasons to use:
– Renewable (won’t run
out.
– Very Cheap
– No real pollution
• Negative reasons to
use:
– Useful ONLY in flat,
wide-open areas, tops of
Mts.
Thermometers- used to measure
temperature.
• Important Temps.
• ABSOLUTE ZERO!!
1) Freezing point of water • The coldest
temperature possible
a) 32 Fahrenheit ( F )
b) 0 Celsius ( C )
• - 459.6 F
2) Boiling point of water
• -273.1 C
a) 212 F
b) 100 C
HEAT TRANSFER Methods
• Radiation- heat rises from a surface.
• Conduction- heat moves THROUGH a surface.
• Convection- Rotating current of Hot, Cold fluid
or air. THE MAIN WAY HEAT in the air is
transferred.
– Hot air Rises because it’s ____________?
– Cold air sinks because it’s ___________ ?
Pressure –ALWAYS moves from
High (H) to Low (L)
Counter Clockwise
L
Pressure –ALWAYS moves from High (H) to Low (L)
Clockwise
H
In Northern Hemisphere:
Lo pressure moves counterclockwise,
Hi pressure moves clockwise.
Winds move opposite in the Southern
Hemisphere.
Fronts-The boundary between 2 air
masses.
• Cold Fronts
1) Cold air meets
warm air
2) Cold air moves
under warm air
3) Results Heavy
rains or snow,
and colder
temperatures
Warm air
(will be
cold)
Cold Air
Triangles point in direction air is moving
Fronts-The boundary between 2 air
masses.
• Warm fronts
1) Warm air meets
cold air
2) Warm air rises
over cold air
3) Forms rainy or
cloudy weather
for days.
4) Brings warm or
humid weather
Movement in
direction circles
point
Fronts-The boundary between 2 air
masses.
• Stationary Front
1) Non moving front
where cold and warm
air meet.
2) Results in rain, snow,
fog or clouds
No movement
Fronts-The boundary between 2 air
masses.
• Occluded Fronts
1) Warm air is caught
between 2 cold fronts
2) Warm air is pushed up
by 2 cold air masses.
3) Results in Cloudy
weather, and cold
ground temperatures.
Slow movement in direction that
symbols point.
FRONTS – Summary
When warm and cold air meet…
1) Warm air rises
2) Clouds form
3) Some type of precipitation forms
a. Rain, if the temperature is above 0 Celsius
b. Snow, Sleet, Freezing Rain, if ground temperature
is below 0 Celsius.
Pressure –ALWAYS moves from High (H) to Low (L)
• Barometer- measures air pressure
• ISOBARS – lines on a weather map that
represent EQUAL PRESSURE
• High pressure changes = High winds
Symbols on a weather map
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Fronts: Cold, Warm, etc.
Isobars
Isotherms (lines of equal temperature)
Wind: Show direction and speed
http://www.ametsoc.org/amsedu/dstreme/ex
tras/wxsym2.html
L
H
H
L
The Water Cycle- cycling of water
from sea to air to land.
C
B
D
A
E Groundwater
• 1) Evaporationliquid water turns
to vapor/gas
• 2) CondensationGas/vapor turns to
liquid. clouds form
• 3) PrecipitationWater falls from
sky. Rain/snow,
etc…
The Water Cycle- cycling of water
from sea to air to land
6) Surface Water – Water
runs to ocean off the
surface.
7) Water soaks into
ground and runs to
lakes, rivers, sea, etc…
Other weather terms:
8) Humidity: amount of water in the air
9) Relative humidity = percentage of water in air,
compared to what it can hold.
– Depends on temperature, pressure, volume of air
10) High humidity = more likely to be hot, or rain
11) Measures humidity with:
Psychrometer – (uses 2 thermometers)
Hygrometer – (uses a needle or dial)
12) Clouds form by:
1.
2.
3.
4.
Water Evaporates
Warm, wet air rises,
Mixes with colder air,
Condensation of water! begins at ‘Dew Point’
(Cloud is formed.)
14) Dew point – Temperature that
water condenses forms clouds, rain
(affected by temp, pressure, etc…)
15) RAIN (liquid H2O)
forms above 0 C.
16) Solid H2O (Ice, Hail,
Sleet, etc..) forms
below 0 C
17) Water falls from sky by:
1. Water collects on ‘CONDENSATION NUCLEI’
(dust, etc..)
2. This forms a water drop
3. Which falls due to weight.
4. Size of drop affected by: Pressure, Temp.,
Humidity, & how many nuclei (dust) are in
the air.
18) Condensation
Nuclei-
Solid particles
that water
collects on.
Ex: Dust,
pollution, ash,
Condensation Nuclei
19) Cloud Seeding – Spraying particles in
the air so water WILL collect & it WILL rain.
http://www.m
etacafe.com
/watch/ytt5zFoLbIdPs
/red_green_
show_cloud
_seeding/
• http://science.howstuffworks.co
m/cloud-seeding1.htm
Cloud Type
Description (what does it
look like?)
What kind of weather
does it mean?
CIRRUS
HIGH, WISPY, MADE OF ICE
FAIR WEATHER
CUMULUS
PUFFY, FORMS AT middle
GENERALLY GOOD, BUT
ALTITUDES
OCCURS AFTER STORMS
(Cumulonimbus)------ (TALL, anvil shaped)------- (Thunderstorms)
STRATUS
LOW LEVEL, GRAY, FLAT
RAIN , CLOUDY
(Nimbostratus)------------
(-----------------------------)
(It IS raining)
20) Fog- Stratus clouds that form at ground
level when WARM Air rises from
water/ground & mixes with cold air
Cloud types
A. NimboStratus
B. Cumulus
C. Stratus
D.Altostratus
E. Cirrocumulus
F. Altocumulus
G.Cumulonimbus
H.Cirrus
CLOUD TYPE - DESCRIPTION
• High Clouds: Cirrus – Wispy, icy
• Intermediate Clouds: Altocumulus are thick,
flattened layers of clouds
• Altostratus - A thick gray layer of sometimes
don't allow the sun or moon to appear.
Cloud types
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Low Clouds
Stratus – lighter gray; rains coming
Nimbus – dark gray; rain and storms
Vertical Clouds:
Cumulus – Fluffy clouds; fair weather usually.
cumuloNimbus – Dark, puffy; Thunderstorms.