Air Temperature Measurement
• Thermometer Types
– Liquid-in-glass
– Bimetallic
– Electrical
• Proper Site Selection
– Height above ground
– Shaded
– Ventilated
Temperature Change with
Elevation
• Generally decreases with increasing
elevation in the troposphere
• Vertical Temperature Profile- Atmosphere
• Importance of elevation of surroundings
– Denver vs. State College
– Denver vs. WV mountains
Seasonality
• Temperature difference between warm and cold
season
• Generally greater over land than water
• Generally increases with distance from water
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Heat capacity difference
Penetration of solar radiation in water
Mixing and currents in water
Evaporation of water
• Cloud cover amount
Prevailing Wind Direction
• Blowing from water or land?
– Charleston, SC vs. San Diego, CA
Ocean Currents
• Water temperature
– Cold currents on west coasts, in general
– Warm currents on east coasts, in general
Air Masses
• A large volume of air (thousands of miles
across by several miles deep) with similar
temperature and moisture characteristics
throughout
• Source Regions = High Pressure Areas
– Air acquires attributes of underlying surface
– Continental vs. Maritime (moisture)
– Polar vs. Tropical (temperature)
Key Figures
• 3.1, 3.2, 3.10, 3.17, 3.20, 3.38