GEOG 131 Chapter Notes - Chapter 2.7(A-B)-2.10: Solar Constant
Document Summary
Solar constant- consistent amount of energy that is radiated on this disc every second: 1366 watts per square meter. The amount of insolation varies during the year because the earth is closer to the sun at certain times of the year: closer to sun during the northern hemisphere"s winter. Perihelion- date of the closest approach (early january) Aphelion- date of the farthest approach (early july) Seasons cannot be explained by out changing distance from the sun. Main factor controlling maximum possible amount of insolation is a site"s position on the earth, speci cally the latitude. Sun angle- angle between incoming light and the surface. Attenuation- sun angle passing through more of the atmosphere to reach the surface: causes less energy to reach the surface. The progression from season to season accompanies changes in the position of the. Orbital plane- the plane in which we orbit the sun tilted relative to the earth: 23. 5 degrees from vertical to orbital plane.
