Transcript Chapter 3 - Cal State LA

Chapter 3: Air Temperature
 Daily Temperature Variations
Maximum temperature recorded late afternoon
 Minimum temperature recorded just before sunrise
 Incoming radiation stops around late afternoon
 Afternoon temperature recorded around

• Later during the summer
• earlier during the winter

All of this, of course, depends on
• Cloud cover and
• Local effects such as
 Santa Ana winds and ‘offshore wind effects’
Daily Temperature Range
 Daily temperature range
 Difference between the daily maximum and daily
minimum temperatures
 Daily range in temperatures is much larger
on clear days than on cloudy days
 Daily Temperature Range Can depend on
Cloud cover
 Humidity

 Annual Temperature Range

Difference between the average temperature of the
warmest and coldest months
Warmest part of day late afternoon
Radiation Cooling
 Occurs at night
 Creates a ‘radiation inversion’
When ground is cooler than air above
 Can observe fog at ground on after a storm

Cold temperatures
At night
Warm daytime
Temps
Clouds help
To keep in temps
Radiation cooling
Causes valleys to
Be cold at bottom
Special Topic
 Record high temperatures
 Record low temperatures
 When it comes to temperature, what is
normal?
 A thousand degrees and freezing to death
Controls of Temperature
 Latitude
Equator
 Polar regions

 Land and water
Beaches
 Mountains
 Deserts

 Ocean currents

California current/Gulf stream
 Elevation

Valleys/mountains/coast
Specific Heat
 Amount of heat needed to raise the
temperature of one gram of a substance by
one degree Celsius
 Takes more heat to raise temperature of
oceans than to raise temperature of land.
 This explains why our ‘oceans’ have memory
of heat stored and can determine climate
over ‘decades’.
Mean Average Temperature
 This is the average temperature of any
weather station for the entire year
 Average is just a fancy name for ‘normal’
 What is normal temperature for L.A. for this
time of year?
 This can be applied to the rainfall total for
this time year
Tables to look at….
 Wind Chill Table……3.2
 How cold the wind makes us feel
 The ‘feels like’ temperature
Measuring air temperature
 Instrument Shelter
 Liquid glass thermometer
 Maximum Thermometer
 Minimum Thermometer
Instrument shelter must be at
Least several feet from the ground
Automation of Weather Instruments
 Automated Surface Observing Systems
(ASOS)
 Electronic weather stations
End of Chapter 3
 Key Terms
 Questions for review
1, 2, 3, 5, 6, 8, 9, 10, 14ab, 15
Questions for thought…..
1, 2, 5, 7, 8