Ozone depletion refers to the thinning of the ozone layer, a protective region in the Earth's atmosphere that absorbs most of the sun's harmful ultraviolet (UV) radiation. This thinning is primarily caused by human-made chemicals, particularly chlorofluorocarbons (CFCs), which break down ozone molecules when released into the atmosphere. The consequences of ozone depletion can lead to increased UV radiation reaching the Earth's surface, resulting in higher rates of skin cancer, cataracts, and other health issues. Additionally, it can harm ecosystems, particularly in marine environments, where increased UV can affect the growth of phytoplankton, a crucial part of the food chain.