Greenhouse gases—facts and information – National Geographic
By trapping heat from the sun, greenhouse gases have kept Earth’s climate habitable for humans and millions of other species. But the same gases that were once beneficial now are out of balance and threaten to change drastically which living things can survive on this planet—and where.Atmospheric levels of greenhouse gases such as carbon dioxide are now higher than at any time in the last 800,000 years, primarily because humans have released them into the air by burning fossil fuels. The gases absorb solar energy and keep heat close to Earth’s surface, rather than letting it escape into space. That trapping of heat is known as the greenhouse effect.The roots of the greenhouse effect concept lie in the 19th century, when French mathematician Joseph Fourier calculated in 1824 that the Earth would be much colder if it had no atmosphere. In 1896, Swedish scientist Svante Arrhenius was the first to link a rise in carbon dioxide gas from burning fossil fuels with a warming effect. Nearly a century later, American climate scientist James E. Hansen testified to Congress that “The greenhouse effect has been detected and is changing our climate now.”Today, climate change is the term scientists use to describe the complex shifts, driven by greenhouse gas concentrations, that are now affecting our planet’s weather and climate systems. Climate change encompasses not only the rising average temperatures we refer to as global warming but also extreme weather events, shifting wildlife populations and and habitats, rising seas, and a range of other impacts.The climate is certainly changing. But what is causing this change? And how does the rising temperature affect the environment, and our lives?