Global warming refers to the rising average temperature of the Earth's atmosphere and oceans over time. The document discusses the causes of global warming, including increased carbon dioxide and methane emissions from human activities like burning fossil fuels and deforestation. The effects of global warming include rising sea levels, more extreme weather events, species extinction, and changes to agricultural yields. While global warming continues to occur, reducing carbon emissions from fossil fuels and preserving carbon sinks can help control the problem.