1. Air Temperature Measurement Thermometer Types –Liquid-in-glass –Bimetallic –Electrical Proper Site Selection –Height above ground –Shaded –Ventilated

2. Temperature Change with Elevation Generally decreases with increasing elevation in the troposphereGenerally decreases with increasing elevation Vertical Temperature Profile- Atmosphere Importance of elevation of surroundings –Denver vs. State College –Denver vs. WV mountains

3. Seasonality Temperature difference between warm and cold season Generally greater over land than water Generally increases with distance from water –Heat capacity difference –Penetration of solar radiation in water –Mixing and currents in water –Evaporation of water Cloud cover amount

4. Prevailing Wind Direction Blowing from water or land? –Charleston, SC vs. San Diego, CACharleston, SC vs. San Diego, CA

5. Ocean Currents Ocean Currents Water temperature –Cold currents on west coasts, in general –Warm currents on east coasts, in general

6. 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)

7. Key Figures 3.1, 3.2, 3.10, 3.17, 3.20, 3.38