Solar constant

About: Solar constant is a research topic. Over the lifetime, 967 publications have been published within this topic receiving 29647 citations.

Chapter 2 – solar radiation

Abstract: Publisher Summary This chapter provides an overview on solar radiation. The availability of solar energy in any location in the world can be studied by two methods. The first involves measurements from a radiation monitoring network and the second is based on the use of physical formulae and constants. Solar constant is a term used to define the rate at which solar radiation is received outside the earth's atmosphere, at the earth's mean distance from the sun, by a unit surface perpendicular to the solar beam. The spectral distribution of direct solar radiation is altered as it passes through the atmosphere by absorption and scattering. The amount of energy absorbed depends on the length of path in which the solar beam traverses. A common method of describing relative energy levels is the air mass, which is the ratio of the actual length the solar beam traverses relative to the depth of the atmosphere with the sun in its zenith position. The chapter also highlights the data from a radiation measurement network. It is difficult to obtain reliable solar radiation data. The most reliable data is associated with the main meteorological stations, but these are often widely dispersed and a considerable distance from the location of any potential application.

Major Chinese cities' solar radiant intensities in winter

Abstract: For lack of direct and scattering solar radiation intensities in current "Table Solar Radiation Intensi- ties of Major Chinese Cities in Winter", hiemal atmospheric transparencies and ratios of scattering solar radia- tion on the horizontal to direct solar radiation on the plane that was perpendicular to the light beam are calcu- lated from the total and scattering solar radiation intensities on the horizontal. And direct, scattering and total solar radiation intensities per hour in major Chinese cities in winter are calculated using the calculated atmos- pheric transparencies and the ratios. In comparison with the data calculated using the cosine rule from the ex- isting table, the results have a higher precision.

Surface temperature of the early Earth and the nature of the terrestrial atmosphere.

Abstract: THE detailed models of solar evolution now available clearly indicate that the luminosity of the Sun has been gradually increasing since it first arrived on the main sequence some 5 × 109 yr ago. If it is assumed that any changes in the orbit of the Earth during this time have been periodic—so that the present orbit is very nearly the average orbit—then it follows that the value of the solar constant has also increased correspondingly. The possibility of a resultant variation in the surface temperatures of the planets is of particular interest for the Earth, which is the only planet at present possessing a considerable quantity of water in the liquid state on its surface.