Burning vegetation only increases the greenhouse effect if it is done on a massive scale without the replacement of the lost vegetation. For example, massive deforestation in developing nations has not been offset by new forest growth elsewhere, and therefore represents a significant portion of man-made greenhouse gas emissions and an imbalance within the carbon cycle. In addition to natural CO2 emissions and water vapor, N2O, or methane, also contributes to the greenhouse effect. Methane is produced from the decomposition of organic materials, and therefore in normal amounts does not have adverse effects on the atmosphere. There has been questions however, about whether or not manmade sources of methane, such as cattle raising and rice growing be more damaging to the environment than CO2. If this were the case, more research would be necessary before any policies involving the greenhouse effect are introduced.

             There has been great controversy over whether or not a build-up of greenhouse gases from human activities is causing the earth's temperature to rise beyond natural levels, and what the effects of this possibility might be. Many people have shown distress at the plausibility or perhaps eventuality of this prospect. This concern is evident in the form of the recent United Nations convention on climate change, better known as the Kyoto protocol which dealt with industrial restrictions on account of increasing man-made CO2 emissions. Under much criticism from American industries, the Clinton administration just signed this controversial document which restricts the release of greenhouse gases into the atmosphere and exhibits a commonly held concern about the greenhouse effect.

             This protocol came about because many scientists believe that rising levels of carbon dioxide emissions will cause climatic changes such as warmer, drier, weather in the northern hemisphere and wetter weather in tropical and subtropical regions.