1. Deforestation
2. Fossil Fuels
3. Global Warming

Deforestation

When trees die and decompose, CO₂ is released. This is part of the normal carbon cycle. When trees are cut down and used for fuel, the CO₂ is also released. The rate at which CO₂ is released as a result of using trees for fuel is increased. However, when trees are used for building construction, furniture, etc, the carbon is not released rapidly into the environment. One would suspect then that harvesting trees for this purpose would result in less CO₂ release into the atmosphere for any given period. That might be correct, except that the tropical forests are being depleted, and with a reduction in vegetation, there is a reduction in photosynthesis. As a result, the carbon cycle is interrupted and the CO₂ is not being converted into sugars and oxygen. CO₂ accumulates. According to University of Maryland researchers ⁽³⁾, the UN reported that deforestation had decreased between 1980s and the 1990s, when, in fact, it had increased, and the CO₂ emissions from deforestation had increased. If CO₂ is increased due to deforestation, one would expect the oxygen level to decrease as a result of decreased photosynthesis.

Fossil Fuels

A third source of carbon dioxide comes from stored CO₂. The carbon found in fossil fuels was laid down over millions of years. Because the organisms did not decay completely, the carbon was never released into the atmosphere as CO₂. Instead, it was stored up in the earth. Once fossil fuel has been recovered, processed and burned, the CO₂, which would normally have been released over tens of millions of years, is suddenly all released within a period of a few hundred years, thus increasing the amount of CO₂ in the environment.

Global Warming

Some scientists have suggested that ocean warming is resulting in increased CO₂ and not the other way around ⁽⁵⁾. This is based on the idea that there is a lot of CO₂ trapped in the oceans, and as the temperature rises, the CO₂ is released, since the solubility of gases is inversely proportional to temperature. Oceans have long been considered to be a sink for atmospheric carbon. If it is releasing CO₂ as a result of warming temperatures, the CO₂ should be decreasing in the oceans.