Chapter 9 - Causes of Atmosphere Pressure

Two basic factors explain the circulation of air in the atmosphere: 1) The Earth receives an unequal amount of heat energy at different latitudes, and 2) it rotate son its axis. The area between the equator and the 35th parallel receives a surplus of net radiation, while the latitudes poleward of the 35th parallel has a deficiency of radiation, with the outgoing amount surpassing that of the incoming amount. The main for this unequal distribution of heat energy is because the sun hits the earth at higher angles, and thus the lower latitudes receive a greater intensity. As a result the equator receives about 2.5 times as much solar radiation as the poles.