Global warming refers to the long-term increase in Earth's average surface temperature, primarily caused by the accumulation of greenhouse gases in the atmosphere. Human activities, such as burning fossil fuels, deforestation, and industrial processes, have contributed to the release of large amounts of carbon dioxide (CO2) and other greenhouse gases into the atmosphere. These gases trap heat, leading to the greenhouse effect and subsequent global warming.

The consequences of global warming are far-reaching and include rising sea levels, melting polar ice caps, more frequent and severe weather events (such as hurricanes, droughts, and heatwaves), disruptions in ecosystems, and the endangerment of various plant and animal species. It also poses risks to human health, agriculture, and economies.

Ozone layer depletion is a related issue, but with a distinct focus. The ozone layer is a region in the Earth's stratosphere that contains a high concentration of ozone (O3) molecules. It plays a crucial role in protecting life on Earth by absorbing most of the Sun's harmful ultraviolet (UV) radiation, preventing it from reaching the Earth's surface.