evidence: The answer is that water vapor is indeed responsible for a major portion of Earth’s warming over the past century and for projected future warming. However, water vapor is not the cause of this warming. This is a critical, if subtle, distinction between the role of greenhouse gases as either forcings or feedbacks. In this case, anthropogenic emissions of CO2, methane, and other gases are warming the Earth. This rising average temperature increases evaporation rates and atmospheric water vapor concentrations. Those, in turn, result in additional warming. [...] Water vapor is a greenhouse gas, and sustained additional water vapor concentrations (resulting from higher average temperatures) will trap additional heat and result in additional warming. Increasing temperatures also influence cloud formation, though the relationship is complex and humidity is but one of many contributing factors. Clouds both trap heat below them, heating the Earth, and increase the reflectivity of the Earth (the albedo) by reflecting light off their white surfaces, cooling the Earth. There remains considerable uncertainty regarding the magnitude of cloud feedbacks, though many researchers believe that the net radiative forcing is either neutral or slightly positive. [...] Claims that water vapor is the "dominant" driver of recently observed climate change are spurious at best. While uncertainties in the magnitude of water vapor feedbacks are one of the key areas concerning climate change, none of this research casts any doubt on the role of carbon dioxide and other anthropogenic greenhouse gases as the initial forcings behind our current climate perturbation.