Global warming is caused by increased levels of greenhouse gases in the atmosphere from human activities like burning fossil fuels. It is already causing changes to the physical, chemical, and biological processes of the Earth that are evident on every continent. If left unaddressed, global warming will have wide-ranging impacts on people, freshwater, oceans, ecosystems, and temperatures worldwide. Solutions include investing in clean energy, green jobs, and smart energy policies to limit pollution while transitioning to more sustainable transportation, housing, and infrastructure.