Energy Exchanges in the
Atmosphere
Atmosphere - blanket of gas that surrounds the earth (the air around us)
Atmospheric Variables that cause weather conditions
TemperaturePressure
Air MovementVisibilityHumidity
Weather - a description of the
atmospheric variables at a given place during a short period of time
Where does most weather occur?
In the TROPOSPHERE which is the LOWEST
PART OF THE ATMOSPHERE
Atmospheric Variables
Temperature Variationsaffected byInsolationAltitudeClouds
Pollution
Pressure Variations
What causes air Pressure?Gravity
Differences in Pressure are due to:
TemperatureAltitude
Humidity
TemperatureWhat is heavier warm
air or cold air?COLD AIR
COLD AIR is more dense and wants to sink causing an increase in
pressure
AltitudeAs altitude increases air pressure DECREASES
Because a smaller amount of air above you
weighs less
Effect ofMoisture Content
orHumidity
on Pressure
Opposite of what you normally expect
As the amount of Water Vapor in the air
INCREASES, the weight of the air DECREASES
Because: water vapor molecules weigh less than dry air molecules
Measuring Air PressureAir Pressure is
measured using a BAROMETER
Atmospheric Pressure is measured in
MILLIBARS and INCHES
Aneroid Barometer
ISOBAR-Line of equal air
pressure.
Isobars are used ON WEATHER MAPS
They help show us the location of HIGHS &
LOWS
Air Movement
Wind -the horizontal
movement of air
Atmospheric Transparency
- a measure of the ability of the
atmosphere to pass light
Dust, Smoke, Water Droplets, etc. in the air
are calledAEROSOLS /
Condensation Nuclei
They directly affect Transparency which
means, as the stuff in the air increases the amount
of light that can pass through decreases.
Ingredients of Weather8min video