Global Warming Greenhouse Effect Shown above is an Infrared Map of the Earth.
Red areas represent regions of high heat retention in the atmosphere.
This is an equatorial band because that is where the atmosphere has the most water vapor. The enhanced greenhouse effect refers to the augmentation of these natural gases by human activities. This is technically known as an Albedo . Note that during Ice Ages, the Albedo of the earth increases as more of its surface is reflective. This, of course, exacerbates the problem.