The document defines key terms related to global warming such as the greenhouse effect, climate change, and global warming. It then discusses the relationship between these concepts and how increased greenhouse gas concentrations can lead to global warming and climate change. The document also outlines some human and natural causes of global warming as well as potential economic, environmental, and health impacts. It notes arguments made by those who dispute the extent of human-caused global warming and concludes by stating that while humans contribute, climate change has natural factors and humans can help mitigate temperature increases.