MEA 200 Lecture Notes - Lecture 8: Radiant Energy, Northern Hemisphere, Convection Cell
Document Summary
Insolation - the solar radiation that reaches the earth"s surface. Measured by the amount of solar energy received per square centimeter per minute. A measure of the reflectivity of the earth"s surface. The fraction of solar energy reflected from the earth back to space. Ice, especially with snow on top of it, has a high albedo: most sunlight hitting the surface bounces back towards space. Surface w/o snow or ice absorbs more heat. Surface w/ snow and ice reflects more heat. Is less than that received in low (latitudes?) Equatorial regions receive more heat per unit area b/c: Implies that sunlight passes through thinner column of atmosphere, leading to less absorption. Earth"s axis of rotation is tilted 23. 5 degrees with respect to plane of the ecliptic. Plane of the ecliptic - plane traced by earth"s orbit around the sun. Northern and southern hemispheres are alternately tilted towards and away from the sun. A net loss is experienced in high latitudes.