Terrestrial radiation

Land/atmospheric interfacial processes which impact climate and biological activity on earth are illustrated in Figure 3. Emissions of carbon dioxide, methane, nitrogen dioxide, and chlorofluorocarbons (CFCs) have been linked to the transmission of solar radiation to the surface of the earth as well as to the transmission of terrestrial radiation to space. Should solar radiation be an internal process or an external driver of the hydrologic cycle, weather, and air surface temperatures Compounds of sulfur and nitrogen are associated with acidic precipitation and damage to vegetation, aquatic life, and physical structures. 

In addition to biogeochemical cycles (discussed in Section 6.5), the hydrosphere is a major component of many physical cycles, with climate among the most prominent. Water affects the solar radiation budget through albedo (primarily clouds and ice/snow), the terrestrial radiation budget as a strong absorber of terrestrial emissions, and global temperature distribution as the primary transporter of heat in the ocean and atmosphere. 

Clouds. Cloud feedback mechanisms are among the most complex in the climate system, due to the many disparate roles played by clouds, which control a large portion of the planetary albedo but also trap terrestrial radiation, reducing the energy escaping to space. To complicate matters further, different t5 es of clouds behave differently in the same environment. In the present climate mode, clouds have... 

Background Radiation—The amount of radiation to which a member of the general population is exposed from natural sources, such as terrestrial radiation from naturally occurring radionuclides in the soil, cosmic radiation originating from outer space, and naturally occurring radionuclides deposited in the human body. 

The greenhouse effect works because of the atmosphere s ability to trap terrestrial radiation. If the atmosphere were less able to trap terres-... 

There are a number of ARCSS data projects that provide CDs. They include the LAII Flux Study Alaska North Slope (data sampler CD) OAII Northeast Water (NEW) Polynya project CD Arctic solar and terrestrial radiation CD, etc. 

The processes of scattering and absorption of radiation in the atmosphere so significantly alter the spectral distribution that any similarity to extra terrestrial radiation is almost coincidental. Experiments with radiation between surfaces have shown that blackbody radiation theory can be extended successfully to many radiation heat transfer situations. In these situations the strict equilibrium requirements of the initial model have so far not proved to be necessary for practical designs. Most importantly the concept of temperature has proved useful in non-equilibrium radiation flux situations(3). 

Average equivalent dose rates received from natural radiation sources are listed in Table 22.8. The values vary appreciably with the environmental conditions. The influence of cosmic radiation increases markedly with the height above sea level, and terrestrial radiation depends strongly on the local and the living conditions. 

In addition to the effects on climate and soils, mentioned above, study of deep-sea sediments and ice cores indicate that, during glacial periods, dust deposition rates were 2-20 times the current values (Thompson and Mosley-Thompson, 1981 Hammer ef fll., 1985 Petit efal., 1990 Rea, 1994 Steffenson, 1997 Reader et al., 1999), possibly because of the effect airborne minerals had on global climate by their interactions with solar and terrestrial radiation (Andreae, 1995, 1996 Duce, 1995 Li et al., 1996 Sokolik and Toon, 1996 Tegen and Lads, 1996 Mahowald et al., 1999). Possible relations between glacial periods and dust have been the subject of intense speculation. 

There are locations of locally elevated terrestrial radiation mainly due to uranium and thorium mineralization. Examples of locally elevated dose rates are ... 

Thus terrestrial radiation levels can vary enormously around the world and result in significant doses, orders of magnitude above the average values reported for man. 

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