Unit 7: Temperatures of the Lower Atmosphere

Average January surface temperatures. Source: http://www.meteo.psu.edu/~j2n/3_1_avetemp_sub.bmp

OBJECTIVES• Discuss the measurement and

characteristics of temperature and heat

• Explain the adiabatic process whereby vertically moving air warms and cools

• Discuss the global distribution of temperatures and their variation in time and space

Temperature, Temperature Scales• What is temperature?• Thermometers• Scales: Celsius, Fahrenheit, Kelvin

Source: http://www.windows2universe.org/physical_science/basic_tools/images/thermometers_kelvin_celsius_fahrenheit_sm.gif

The Vertical Distribution of Temperature• Environmental Lapse Rate

• Adiabatic Lapse Rates -Dry Adiabatic Lapse Rate (DALR) - Saturated Adiabatic Lapse Rate (SALR)

• Stability -stable -inversions (ground, subsidence) -unstable -conditionally stable

• Stability and Air Pollution

Source: http://www.fas.org/irp/imint/docs/rst/Sect14/Sect14_1b.html

James Glaisher and his assistant, Coxwell, during a balloon flight on September 5, 1862.

Concept of Stability

Source: http://epswww.unm.edu/facstaff/gmeyer/envsc101/wk11atmcompcirc.htm

Environmental lapse rate conditions

Source: https://www.meted.ucar.edu/sign_in.php?go_back_to=http%253A%252F%252Fwww.meted.ucar.edu%252Fmesoprim%252Fbandedprecip%252Fprint.htm

In an unstable atmosphere numerous thunderstorms billow up as viewed over southern Florida looking south.

Downtown Los Angeles is a leading city of air pollution due to poor vertical and horizontal mixing. Throughout the summer, there is a restrictive temperature inversion over the region. Adopting the strictest air pollution controls in the world, the air quality has improved remarkably.

Fig. 8.7 3rd ed.

Horizontal Distribution of Temperature• Temporal cycles -Daily cycle -Annual cycle

• Heating of land vs. water -maritime effect -continental effect, continentality

• Global temperature variations -seasonal variations -isotherms and temperature gradients

Daily Radiation Patterns

Figure 3.12

Land–Water Heating Differences

Figure 3.20

The annual range in sea surface temperature (A) and the lag between maximum solar heating and the date of maximum temperature (B).

Fig 8.9-annual temperature regimes for inland vs coast

Effects of Latitude

Figure 3.17

Source: http://www.verkhoyansk.climatemps.com/

Annual Temperature Regime in Siberia

Mean sea-level air temperatures, in Fahrenheit for January

Source: http://apollo.lsc.vsc.edu/classes/met130/notes/chapter3/graphics/jan_temps.jpg

Mean sea-level air temperatures, in Fahrenheit for July

Source: http://apollo.lsc.vsc.edu/classes/met130/notes/chapter3/graphics/july_temps.jpg

Global Temperature Ranges

Figure 3.28

Urban Heat Island

Figure 3.30

Air Temperature and the Human Body

• Wind chill– Correlates cold and wind speed

• Heat index– Correlates heat and humidity

Wind Chill Table

Figure 1

Heat Index Table

Figure 2