Presentation on theme: "Air Temperature. ► Temperature : a measure of the average speed at which molecules are moving or vibrating."— Presentation transcript:
► Temperature : a measure of the average speed at which molecules are moving or vibrating.
► Air temperature the rate of motion of gas molecules in the atmosphere as a result of the absorption of energy measured by a thermometer
Temperature scales ► Celsius water freezes at 0 o water boils at 100 o ► Fahrenheit water freezes at 32 o water boils at 212 o ► Kelvin no molecular motion at 0 K water freezes at 273 K water boils at 373 K
Conversions ► o F = (1.8 x o C) + 32 ► o C = 0.56 ( o F - 32) ► K = o C + 273
What determines the temperature of a place? 1. Insolation (daily and annual cycles) 2. Latitude 3. Urban/Rural Surface 4. Coastal vs. Interior location 5. Elevation
1. Insolation A. Changing angle of noon sun throughout the year changes temperature on a seasonal basis.
► Why temperature difference between equinoxes?
► Spring : at end of cold, short day period more energy loss ► Autumn : at end of warm, long day period more energy gain
1. Insolation B. Changing angle of sun throughout the day changes temperature on a daily basis.
► lag between max insolation and max temperature because highest temp at time of max ABSORBED insolation
2. Latitude ► Higher latitudes receive less insolation than lower latitudes sun’s rays are more oblique daylength is variable Net energy surplus in tropics; net energy deficit in polar regions
4. Coastal vs. interior locations ► Water bodies have a moderating effect on temperature.
► “Land heats up and cools down more rapidly than water.” Therefore: ► Coastal: smaller temperature ranges than continental locations. ► Coastal locations have their maximum temperatures well after maximum insolation.
► Lake effect in Duluth is an example of changes in temperature due to being close to a large body of water.
5. Altitude / Elevation ► Temperature decreases as elevation increases. less mass, less pressure, less absorption
Exception: temperature inversion
► Conditions favorable for a temperature inversion: cool, clear, calm night