The document discusses the greenhouse effect and its causes. It begins by explaining the natural greenhouse effect process whereby the Earth's atmosphere traps heat from the sun. It then discusses factors that enhance the greenhouse effect, including human activities like the burning of fossil fuels, deforestation, electrical appliances, and population growth which increase greenhouse gas emissions. The document also notes some of the consequences of an enhanced greenhouse effect, such as changes in weather patterns, rising sea levels, and effects on farming and food availability.