Page 103 - Intro to Space Sciences Spacecraft Applications

Introduction to Space Sciences and Spacecraft Applications
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thermosphere
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TEMPERATURE (OK)
Figure 4-6. The “standard” atmosphere. The temperature of the atmosphere
varies with altitude.

mid-latitudes. This temperature variation delineates several distinct
regions also identified in the figure.

Troposphere. The troposphere is an area of unstable air where most of the
weather we experience is formed. The region is unstable due to the turbu-
lent convection of air heated at the surface by the infrared energy that the
earth emits due to its temperature, which is a result of the earth’s absorp-
tion of solar radiation. As can be seen, the temperature decreases linearly
through this region until we reach the tropopause-the transition region
between the troposhere and the stratosphere-where the temperature
remains relatively constant (isothermal).

Stratosphere. Unlike the troposphere, the stratosphere is relatively non-
turbulent. Temperature increases with altitude through this region due to
the continued absorption of the earth’s infrared radiation by H20 and C02
molecules and absorption of solar ultraviolet radiation by the ozone that
exists at the top of this region.

Mesosphere. Above the isothermal layer at the top of the stratosphere (the
stratopause), the mesosphere is a region where the temperature once again