The sun emits shortwave radiation because it is extremely hot and has a lot of energy to give off. The ground heats up and re-emits energy as longwave radiation in the form of infrared rays. Earth emits longwave radiation because Earth is cooler than the sun and has less energy available to give off.
III. Solar Radiation Outside the Earth's Atmosphere - Engineering LibreTexts
Figure A shows the Atmospheric Window of the wavelengths that enter our atmosphere. Our atmosphere is transparent to radio waves, visible light, and some infrared and UV radiation. Basic information about skin cancer. April 24, Long-wave radiation is emitted by the atmosphere and propagates both upward and downward. According to the Stefan-Boltzmann law , the total amount of long-wave energy emitted is proportional to the fourth power of the temperature of the emitting material e.
The magnitude of this radiation reaching the surface depends on the temperature at the height of emission and the amount of absorption that takes place between the height of emission and the surface.
A larger fraction of the long-wave radiation is absorbed when the intervening atmosphere holds large amounts of water vapour and carbon dioxide. Clouds with liquid water concentrations near 2.
Clouds with lower liquid water concentrations require greater depths before complete absorption is attained e. The amount of long-wave radiation emitted corresponds to the temperature of the lowest levels of the cloud. Clouds with warmer bases emit more long-wave radiation downward than colder clouds. The magnitude of heat flux by conduction below a surface depends on the thermal conductivity and the vertical gradient of temperature in the material beneath the surface. Soils such as dry peat , which has very low thermal conductivity i.
In contrast, concrete has a thermal conductivity about 75 times as large i. In water, the thermal conductivity is relatively unimportant, since, in contrast to land surfaces, insolation extends to substantial depths in the water; in addition, water can be mixed vertically.
Vertical mixing convection occurs in the atmosphere as well as in bodies of water. This process of mixing is also referred to as turbulence. It is a mechanism of heat flux that occurs in the atmosphere in two forms.
- Reconnection Space.
- Radiation in the Atmosphere, Volume 12.
- Rotaviruses: Methods & Protocols (Methods in Molecular Medicine).
When the surface is substantially warmer than the overlying air, mixing will spontaneously occur in order to redistribute the heat. This rate is called the adiabatic lapse rate the rate of temperature change occurring within a rising or descending air parcel. Introduction to the use of a modern radiation model.
To get a basic introduction to the theory of scattering, absorption and emission of electromagnetic radiation in atmospheres, and an introduction to an existing radiation transport model with applications on for example the analysis of data from the UV, visible and IR area.
Random radiation clouds found in atmosphere at flight altitudes
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