What Causes Global Warming
Causes Of Global Warming The greenhouse effect The average surface temperature of Earth is maintained by a balance of various forms of solar and terrestrial radiation. Solar radiation is often called “shortwave” radiation because the frequencies of the radiation are relatively high and the wavelengths relatively short—close to the visible portion of the electromagnetic spectrum . Terrestrial radiation, on the other hand, is often called “longwave” radiation because the frequencies are relatively low and the wavelengths relatively long—somewhere in the infrared part of the spectrum. Downward-moving solar energy is typically measured in watts per square metre. The energy of the total incoming solar radiation at the top of Earth’s atmosphere (the so-called “ solar constant ”) amounts roughly to 1,366 watts per square metre annually. Adjusting for the fact that only one-half of the planet’s surface receives solar radiation at any given time, the average surface ins