Download Water properties Air circulation Climate Weather Water Properties

Water Properties: Hydrogen bonding
Water properties
Air circulation
Climate
Weather
• High surface tension
• High solubility
• Unusual thermal
properties
• Unusual density
Water Properties: Change of state
Water Properties: Change of state
Heat: total kinetic energy of moving molecules in a substance
Heat: total kinetic energy of moving molecules in a substance
Temperature: average kinetic energy
Temperature: average kinetic energy
Water Properties: Heat capacity
Air circulation
Ability to absorb or lose heat without changing temperature
• Air pressure depends on air density
- Temperature
- Water vapor
High density
High pressure
Heat (
Low density
Low pressure
)
Heat: total kinetic energy of moving molecules in a substance
Temperature: average kinetic energy
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Air circulation
Air circulation
• Air pressure depends on air density
- Temperature (!T "density)
- Water vapor (!H 2O !density)
High density
High pressure
Low density
Low pressure
Air circulation
Air circulation: Rotating Earth
Sun
Air circulation: Rotating Earth
Air circulation: Rotating Earth
Rotation causes the Coriolis effect - the deflection of a moving
body due to the change in rotational velocity with latitude
•
Fastest at the equator
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Air circulation: Rotating Earth
Atmospheric circulation
Rotation causes the Coriolis effect - the deflection of a moving
body due to the change in rotational velocity with latitude
Initial picture:
No Earth rotation, 1 circulation
cell per hemisphere
Atmospheric circulation
Atmospheric circulation
Initial picture:
Closer to reality:
No Earth rotation, 1 circulation
cell per hemisphere
Coriolis deflects surface winds,
3 circulation cells per hemisphere
Atmospheric circulation
Atmospheric circulation
Equatorial climate
• Intense solar radiation
• Surface water evaporates
• Warm, moist air rises
• Atmospheric low pressure
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Atmospheric circulation
Atmospheric circulation
Equatorial climate
Subtropical climate
• Intense solar radiation
• Surface water evaporates
• Warm, moist air rises
• Atmospheric low pressure
• Cool air sinks
• High pressure
• Sinking air warms
• Warm air causes evaporation
• Water vapor absorbs heat
• Surface winds move N, S
Atmospheric circulation
Atmospheric circulation
Subtropical climate
Temperate climate
• Cool air sinks
• High pressure
• Sinking air warms
• Warm air causes evaporation
• Water vapor absorbs heat
• Surface winds move N, S
• Warm, moist air rises
• Low pressure
• Precipitation
• Water vapor releases heat
Atmospheric circulation
Atmospheric circulation
Temperate climate
Polar climate
• Warm, moist air rises
• Low pressure
• Precipitation
• Water vapor releases heat
• Cool air sinking
• High pressure
• Evaporation (liquid to gas)
• Water vapor absorbs heat
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Atmospheric circulation
Climate: Temperature
Polar climate
• Cool air sinking
• High pressure
• Evaporation (liquid to gas)
• Water vapor absorbs heat
Weather: Hurricanes
Weather: Precipitation
• Rotating mass of low pressure air
• Strong winds, torrential rain
Weather: Hurricanes
When warm, moist air rises
• Volume expands
• Temperature decreases
• Water vapor condenses (rain!)
Weather: Seattle
When warm, moist air rises
• Volume expands
• Temperature decreases
• Water vapor condenses (rain!)
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Weather: Seattle
Extra slides
Jet stream
Solar Heating
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Angle of incidence of solar rays per area
• Equatorial regions more heat
• Polar regions less heat
Thickness of atmosphere
Albedo (reflectivity)
Duration of day/night
Seasonal changes
Solar Heating
Air Properties: Pressure
Atmospheric
circulation
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