Critical Facts 1. There are at least 22 climate change causes (drivers).
The sheer number of drivers "speaks" to the complexity of understanding climate change. The principal influence of each of the drivers and their impact is shown in the table below. Some drivers exert a more immediate influence while others contribute over much longer time scales. CO2 (carbon dioxide) is one of the drivers and while everyone agrees that CO2 does contribute to climate change as a greenhouse gas, the magnitude of CO2 's influence has not been settled within the overall scientific community, the political systems, the media or the population in general. We have determined that CO2 's influence, while significant at low concentrations in the atmosphere, is of minor impact as more and more is added to the atmosphere, a view that we address in the following Critical Facts list. For an expanded discussion of each of these 18 climate drivers, refer to our Recommended Reading List, "Fire, Ice, Paradise".