This document provides a simplified explanation of the greenhouse effect and global warming. It explains how greenhouse gases in the atmosphere trap heat similarly to how a greenhouse works, warming the Earth's surface. An increase in greenhouse gases from human activities is enhancing the greenhouse effect and causing global warming. Some effects of global warming include melting polar ice caps, changes to ecosystems, and more frequent extreme weather events. The document lists various greenhouse gases and their sources to help explain the causes and impacts of climate change.