Why is the global climate changing?
In a nutshell, humans are altering the radiative balance of the Earth. The balance between incoming energy and outgoing energy dictates the temperature of the Earth. Temperatures increase when more energy is received than lost. The Earth’s surface absorbs shortwave radiation from the Sun. This energy is then redistributed by atmospheric and oceanic circulation and radiated back to space at longer, infrared wavelengths. On average for the Earth as a whole, the incoming solar radiation energy is balanced approximately by the outgoing terrestrial radiation. Global climate can be affected by any factor that alters the radiation received from the Sun or lost to space, or that alters the redistribution of energy within the atmosphere and between the atmosphere, land, and ocean. A change in the net radiative energy available to the global Earth-atmosphere system is termed radiative forcing. Positive radiative forcing tends to warm the Earths surface and lower atmosphere, whereas negative radi
