The Earth is surrounded by an enormous atmospheric layer able to absorb the sun's shortwave radiation and prevent the Earth from becoming too hot. After the Earth absorbs the heat of the sun's rays it releases it as long wave radiation. When this happens, the atmospheric layer blocks some of the long wave radiation from dissipating into space thus giving the earth a constant average surface temperature of 15 degrees Centigrade.
地球表面包裹著一層大氣，可以吸收太陽的短波輻射，使地球不至於太熱，而地球在吸收太陽光熱後，會以長波輻射的方式釋放出能量，此時，這層大氣又阻擋了部分的長波輻射溢散到太空，使地面維持在平均溫度攝氏 15 度的狀態。