Solar radiation distribution

The distribution of solar radiation, including surface radiation exchange, can account for solar heat source variations in time and local space. 

Solar radiation is distributed in the first room and not transmitted into adjacent rooms through an internal window (more sophisticated modeling may allow for this). 

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. 

The spectral distribution of this radiation is given in Table 4.3, from which we can easily see that radiation with wavelengths below 150nm represents only a tiny fraction of the total. The energy distribution of the solar radiation corresponds to that from a black body with a temperature of around 5,000 K. 

Table 4.3 Spectral distribution of the optical solar radiation in the Earth s atmosphere. Data taken from the Smithsonian Physical Tables (1959)...

The rainfall regime in arid areas is characterized by low, irregular and unpredictable precipitation, often concentrated in a few rainstorms, creating humid conditions in the soil for a short period and over a limited area. In many arid areas, several years may elapse between successive rainfalls. The moisture supplied to the soil from rain is offset by evaporation, that is related to air temperature, air humidity and intensity of solar radiation. Because of the irregular rainfall distribution, mean precipitation values have little meaning, if not also the range of variation is indicated. 

Specific solar radiation conditions are defined by the air mass (AM) value. The spectral distribution and total flux of radiation outside the Earth s atmosphere, similar to the radiation of a black body of 5,900 K, has been defined as AM-0. The AM-1 and AM-1.5 are defined as the path length of the solar light relative to a vertical position of the Sun above the terrestrial absorber, which is at the equator when the incidence of sunlight is vertical (90°) and 41.8°, respectively. The AM-1.5 conditions are achieved when the solar flux is 982 Wm2. However, for convenience purpose the flux of the standardized AM-1.5 spectrum has been corrected to 1,000 Wm2. 

Significant economies of computation are possible in systems that consist of a one-dimensional chain of identical reservoirs. Chapter 7 describes such a system in which there is just one dependent variable. An illustrative example is the climate system and the calculation of zonally averaged temperature as a function of latitude in an energy balance climate model. In such a model, the surface temperature depends on the balance among solar radiation absorbed, planetary radiation emitted to space, and the transport of energy between latitudes. I present routines that calculate the absorption and reflection of incident solar radiation and the emission of long-wave planetary radiation. I show how much of the computational work can be avoided in a system like this because each reservoir is coupled only to its adjacent reservoirs. I use the simulation to explore the sensitivity of seasonally varying temperatures to such aspects of the climate system as snow and ice cover, cloud cover, amount of carbon dioxide in the atmosphere, and land distribution. 

Parrish, J. T. 1985. Latitudinal distribution of land and shelf and absorbed solar radiation during the Phanerozoic, Open-File Report 85-31. Washington, D.C. U.S. Department of the Interior, Geological Survey. 

Fig. 40 Energy distribution of solar radiation (according to CIE, No. 20) and filtered xenon arc light (Xenotest 1200) [102].

Figure 2, Plots of the efficiencies tje, rjY, rfp, and -qc as a function of the wavelength Xg corresponding to the band gap E. The distributions have been calculated for AM 1.2 solar radiation (taken from distribution T/S of Ref. 6). Curves, E, Y, P, and C are plots of -qEy my VPy rjc as defined in Equations 3,8,12, and 16, respectively. Tfc has been calculated for 0.6, 0.8, and 1.0 eV energy loss, respectively, as...

In short, the direct effects of aerosol particles in terms of backscattering solar radiation out to space and hence leading to cooling are reasonably well understood qualitatively and provided the aerosol composition, concentrations, and size distribution are known, their contribution can be treated quantitatively as well. However, major uncertainties exist in our knowledge of the physical and chemical properties, as well as the geographical and temporal variations, of aerosol particles and it is these uncertainties that primarily limit the ability to accurately quantify the direct effects at present. 

If this excess absorption by clouds is ultimately shown to be a real phenomenon, then an increased cloud formation and extent due to anthropogenic emissions may alter the radiative balance of the atmosphere not only through increased reflectance but also through increased absorption of solar radiation. Such an effect could impact atmospheric temperatures, their vertical distribution, and circulation, as well as surface wind speeds and the surface latent heat flux (Kiehl et al., 1995). Hence establishing if this is truly excess absorption, and if so, its origins, is a critical issue that remains to be resolved. 

We measured H202 vertical profiles in Lake Erie (14, 18) and noted the similarity with oceanic profiles (23, 24). The major difference is the depth to which H202 is mixed in oceanic environments. To emphasize the effect of solar radiation and wind speed on the distribution of H202 in the epilimnion, we measured four vertical profiles of H202 concentration and temperature in Jacks Lake on 4 days, September 11-14, 1990, all at 4 00 p.m. 

Leckner. B. (1978) The spectral distribution of solar radiation at the Earth s surface - elements of a model. Solar Energy.. 20, 143. 

Krasnopol skiy, V.A. (1966) The ultraviolet spectrum of solar radiation reflected by the terrestrial atmosphere and its use in determining the total content and vertical distribution of atmospheric ozone. Russian Geomagnetism andAeronomy 6 236-242. 

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