The temperature at which all molecular motion ceases (0 degrees Kelvin)
Particulates (very small liquid or solid particles) that are suspended in the atmosphere.
The envelope of gases that surrounds the earth.
A trace gas that absorbs terrestrial radiation.
Mass per unit volume.
The ratio of pressure to the product of temperature and density is always the same (P/DT = 1).
International Standard Atmosphere (ISA)
A model atmosphere based on average vertical distributions of pressure, temperature, and density as prescribed by international agreement.
A deep layer of charged particles (ions and free electrons) that extends from the lower mesosphere upward through the thermosphere.
The energy that exists by virtue of motion.
The upper limit of the mesosphere and the boundary between the mesosphere and thermosphere; slightly more than 280,000 feet MSL.
A layer of the atmosphere where temperature decreases with height. The mesosphere is located immediately above the stratopause, between about 160,000 and 280,000 feet.
Makes up 78% of the atmosphere. Nitrogen does not contribute to weather-producing processes under ordinary atmospheric conditions, although exceptions occur when it is subjected to very high temperatures.
Oxides of Nitrogen
Nitrogen combines with oxygen under extremely high temperatures to form these air pollutants.
21% of the atmosphere and its most important role is to support life. Concentration decreases with altitude. Supports combustion and contributes to both the formation and the destruction of air pollutants through chemical combinations with other gases.
An unstable form of oxygen; greatest naturally occurring concentrations are in the stratosphere (ozone layer); abosrbs damaging ultraviolet solar radiation; prolonged exposure to high concentrations causes respiratory problems and causes some materials to deteriorate.
The region of the ozone layer that has a lower-than-normal concentration of ozone.
A layer of ozone found in the lower stratosphere near 80,000 feet MSL. Characterized by a relatively high concentration of ozone, this layer absorbs damaging UV radiation and is the cause of the increase of temperature with height in the stratosphere.
Very small liquid or solid particles in the atmosphere. When suspended in the atmosphere, they are called aerosols.
The force exerted by the moving molecules of the gas on a given area.
Standard Atmosphere (ISA)
An average atmosphere based on the following characteristics: -A surface temperature of 15 deg C (59 deg F) and a surface pressure of 1013.25 mb (29.92 in. Hg.) at sea level, -A lapse rate in the troposphere of approx. 2 deg C per 1,000 ft, -A tropopause of approx. 36,000 ft with a temperature of -56.5 deg C. -An isothermal lapse rate in the stratosphere to an altitude of approx. 80,000 ft.
Occurring at an altitude of about 160,000 ft MSL, the stratopause is the top of the stratosphere.
The atmospheric layer above the tropopause, average altitude of base and top are 36,000 ft and 160,000 ft. In the ISA, the average, mid-latitude stratosphere is characterized by an isothermal lapse rate at the bottom of the layer, with an increase of temperature above.
In general, the degree of hotness or coldness as measured on some definite temperature scale by means of any of various types of thermometers. Also, a measure of the direction of heat flow; and a measure of the mean kinetic energy of the molecules.
The outer layer of the atmosphere that is directly adjacent to the mesosphere and where the temperature increases with an increase in altitude. The base of the thermosphere is about 280,000 ft.
The boundary between the troposphere and stratosphere, usually characterized by an abrupt change of lapse rate. In the ISA, the height of the tropopause is about 36,000 ft MSL. The height of the tropopause varies with season, latitude, and the presence or absence of local weather disturbances.
That portion of the atmosphere between the earth's surface and approximately 36,000 ft MSL. The average troposphere is characterized by decreasing temperature with height, and is the atmospheric layer where the great majority of clouds occur.
The gaseous form of water. Varies from trace amounts to 4% within our atmosphere.
What gases make up the earth's atmosphere?
78% Nitrogen, 21% Oxygen, and 1% other gases.
True or False: Carbon dioxide absorbs terrestrial radiation.
What are carbon dioxide and ozone also known as?
What are some ways to reduce pressure?
By cooling, by reducing mass, or by increasing volume.
When the density within a vessel is kept constant, how would you reduce its pressure?
By lowering the temperature.
When the temperature and volume of a vessel remain the same, how would you reduce its pressure?
The pressure could only be reduced by removing gas.
When the temperature and mass of the molecules in a vessel remain the same, how can we lower the pressure?
By increasing the volume of the vessel.
What is the distance in nautical miles from pole to equator?
What is the circumference of the earth?
What is the radius of the earth?
Why is water vapor an important gas for weather production?
Because it can also exist as a liquid (water) and as a solid (ice). These contribute to fog, clouds, precipitation, and icing.
Where is the greatest concentration of ozone located?
Between 50,000 and 100,000 ft (within the stratosphere).
Why are particulates important?
Because they intercept solar and terrestrial radiation, provide surfaces for condensation of water vapor, reduce visibility, and can even foul engines (in the worst cases).
T/F: The greater the average kinetic energy, the lower the temperature.
FALSE: The greater the average kinetic energy, the GREATER the temperature.
What is absolute zero on the Kelvin scale?
0 degrees Kelvin - the point where all molecular motion ceases.
T/F: In general, density decreases with height.
T/F: Density can also be critically low near the ground because of very high surface temperatures.
What are the three standard atmospheric pressure values at sea level?
14.7 lbs/sq in 1013.25 mb 29.92 in. Hg.
What are two notable features of pressure curve?
1) Pressure always decreases with altitude. 2) Rapid decrease in pressure just above the ground and the very gradual decrease at the higher levels.
In the lower troposphere, how much altitude is gained for every one inch decrease of mercury?
Pressure decreases about one inch of mercury for each 1,000 feet of altitude gain.
In the lower troposphere, pressure decreases about _____ mb for each 1,000 feet of altitude gain.
What is the Gas Law?
The ratio of pressure to the product of density and temperature is always the same. (P/DT = R)
At least half of the earth's atmosphere is located below _______ feet.
At least 75% of the earth's atmosphere is located below _______ feet.
At least 90% of the earth's atmosphere is located below _______ feet.
Which atmospheric layer is located from sea level to 36,000 feet?
Which atmospheric layer is located from 36,000 feet to 160,000 feet?
Which atmospheric layer is located from 160,000 feet to 280,000 feet?
Which atmospheric layer is the highest layer, with temperatures increasing with altitude?
What are the four atmospheric layers we discussed in this chapter?