How does carbon dioxide trap heat? That carbon dioxide and other greenhouse gases trap heat is something scientists have known about for more than a 150 years. The underlying concept behind climate change is simple enough that school children can replicate the chemistry and physics and so can you. The why and how it happens is only a bit more complicated. Just as a greenhouse traps heat or a blanket keeps you warm, carbon dioxide, methane and other gases—nicknamed greenhouse gases—trap heat from the sun that would otherwise bounce back into space. The blanket or greenhouse aren't perfect analogies but they give the right sense of what is happening, said University of Pennsylvania climate scientist Michael Mann. Without the greenhouse effect, Earth would be freezing, scientists said. The greenhouse effect, which is natural but then put on steroids by carbon pollution, is responsible for conditions that make life on Earth possible. But there can be too much of a good thing. Scientists point to the runaway greenhouse effect on Venus as a case example. In fact, former top NASA climate scientist James Hansen, often called the Godfather of global warming, initially was studying what was happening on Venus before he turned to his home planet and accurately warned people about a smaller scale version happening here. Heat from the sun comes through the atmosphere and then bounces back as infrared radiation, a different wavelength than it came in on. If you put your hand over a dark rock on a warm sunny day you may be able to feel that heat heading off Earth. The greenhouse effect is when that heat tries to escape Earth, but some of it is trapped by different chemicals in the atmosphere, such as water vapor, carbon dioxide and methane. In the 1820s, French mathematician and scientist Joseph Fourier figured that something keeps Earth warmer than a bare rock out in space: Our atmosphere. "Our atmosphere, thrown as a barrier across the terrestrial rays, produces a local heightening of the temperature at the Earth's surface," Irish physicist John Tyndall said in 1862, identifying water vapor and carbon dioxide as natural greenhouse gases trapping heat. Then in 1896, Swedish chemist Svante Arrhenius took it one step further and calculated that changes in carbon dioxide may affect the climate. Read More: https://phys.org/news/2022-10-climate-carbon-dioxide.html