Download Winds - Hicksville Public Schools

Heating of Land and Water
Land Heats up faster and Cools down faster than water
Winds
•Movement of air from an area of high
pressure to an area of low pressure.
•Winds are caused by differences in air
pressure.
•Differences in air pressure are caused
by the unequal heating of the Earth.
• Wind-chill factorMeasure of cooling. It
combines temperature
with wind speed.
• The name of the wind
tells you where the wind
is coming from. (South
wind blows from the
South)
Local Winds
• Sea Breeze- blows
from ocean or lake
• Land Breeze- blows
from land to a body of
water.
Global Winds
• Global Convection Currents- Differences in air
pressure causes winds to blow from the poles
toward the equator.
Coriolis Effect
Earth’s rotation makes winds curve to the right
(clockwise) in the Northern hemisphere and to the left
in the southern hemisphere (counter clockwise).
Air masses
• Air Mass- body of air that has similar
temperature, humidity, and air pressure.
• Polar- cold
• Tropical- warm
• Maritime- form over oceans, humid
• Continental- form over land, dry
Air Masses
• Maritime Tropical- over ocean, humid,
warm
• Maritime Polar- over ocean, humid, cold
• Continental Tropical- over land, dry, warm
• Continental Polar- over land, dry, cold
In the US air masses are commonly moved
by winds. They move from west to east.
Fronts
Colliding air masses can form four types of fronts:
cold fronts, warm fronts, Stationary fronts and
occluded fronts
All Fronts have the following in common:
• The warm air rises.
• The cold air sinks.
• When the cold and warm air touch
condensation will happen and clouds will
form.
• Clouds result in precipitation.
Cold Front
Fast moving cold air mass overtakes a warm
air mass. Results in clouds, precipitation
and thunderstorms. After- clear skies and
lower temperatures.
Warm Front
Fast moving warm air mass overtakes a cold air
mass. Results in clouds and precipitation. Afterwarm and humid
Stationary Front
Cold and warm air masses meet but neither
moves. Results in clouds and precipitation.
Occluded Front
Warm air mass is caught between two cold air
masses. Results in cooler temperatures clouds
and precipitation.
Symbols
Isolines
Lines on maps that connect equal
measurements at a given time.
There are three types:
a) Isobar- equal atmospheric pressure.
(mb)
b) Contour lines- equal altitude. (m)
c) Isotherm- equal temperature. (Celsius or
Farenheit)
Wind Speed
Measured with an anemometer
Station Models
Weather Maps
• High PressureClear Weather
• Low PressureStormy weather
Storms
A storm is a violent disturbance in the
atmosphere.
Thunderstorms- thunder and lightening
Avoid places where lightning may strike, and
objects that conduct electricity.
Tornado
Fast whirling funnel
shaped cloud that
reaches down from a
storm cloud to touch
the ground .
The safest placebasement
Hurricane
Begins over warm ocean
water as a low pressure
area or tropical
disturbance.
If asked to evacuate leave
the area.