amandadouglas 's List: Solar Radiation

. Solar  radiation
 
 
1. Explain in terms of the  electromagnetic spectrum we have studied  [remind yourself here] what are the types and  amounts [descriptions are sufficient] of light produced by our star. State the other [only two] sources of energy  input on Earth. 
2. State and explain how  the solar radiation that strikes Earth is distributed [see here]. Be sure to  explain the concept of albedo and insolation.
    
3. Explain how  the tilt of the Earth causes seasonal changes on Earth. Be sure to discuss the  angle of sunlight with respect to latitude, not distances. Explain the seasonal effects on length of day,  growing seasons changes in average temperature. 
4. Identify a satellite responsible for gathering  evidence about solar radiation flux. Describe its age, orbit and what it  measures.
   

 

 

 

 

 

 

Three atmospheric processes modify the solar  radiation passing through our atmosphere destined to the Earth's surface. These  processes act on the radiation when it interacts with gases and suspended  particles found in the atmosphere. The process of scattering occurs when small  particles and gas molecules diffuse part of  the incoming solar radiation in random directions without any alteration to the  wavelength of the electromagnetic energy (Figure 7f-1). Scattering does,  however, reduce the amount of incoming radiation reaching the Earth's surface. A  significant proportion of scattered shortwave solar radiation is redirected back  to space. The amount of scattering that takes place is dependent on two factors:  wavelength of the incoming radiation and the size of the scattering particle or  gas molecule. In the Earth's atmosphere, the presence of a large number of  particles with a size of about 0.5 microns results in shorter wavelengths being  preferentially scattered. This factor also causes our sky to look blue because  this color corresponds to those wavelengths that are best diffused. If  scattering did not occur in our atmosphere the daylight sky would be  black.

Solar radiation is becoming increasingly appreciated because of its influence  on living matter and the feasibility of its application for useful purposes. It  is a perpetual source of natural energy that, along with other forms of  renewable energy, has a great potential for a wide variety of applications  because it is abundant and accessible. Solar radiation is rapidly gaining ground  as a supplement to the nonrenewable sources of energy, which have a finite  supply.

The solar radiation spectrum

Solar radiation is commonly divided into various regions or bands on the  basis of wavelength (Table 1). Ultraviolet radiation is that part of the  electromagnetic spectrum between 100 and 400 nm. It is, in turn, divided rather  arbitrarily from the viewpoint of its biological effects into three major  components (Fig. 1). Table 1. Spectral bands of incoming solar energy and  atmospheric effects.