How does global warming work?

Human activity affects global surface temperatures by changing Earth’s radiative balance—the “give and take” between what comes in during the day and what Earth emits at night. Increases in greenhouse gases—i.e., trace gases such as carbon dioxide and methane that absorb heat energy emitted from Earth’s surface and reradiate it back—generated by industry and transportation cause the atmosphere to retain more heat, which increases temperatures and alters precipitation patterns.