Global warming refers to the long-term rise in the average temperature of the Earth's climate system due to human activities that increase heat-trapping greenhouse gases. The main causes of global warming are burning fossil fuels like coal, oil and gas, agriculture, deforestation, and industrial processes. Some of the impacts of global warming include rising sea levels, stronger extreme weather events, damage to coral reefs and glacial melting, which can threaten both humans and ecosystems. While the concept remains controversial, the majority of scientific evidence supports that global warming poses severe risks if left unaddressed.