Modern models of climate change are grounded in observable evidence and reasonable inference, so they can be regarded as factual. Global warming happens when sunlight warms the Earth's surface and causes it to radiate heat back up into the atmosphere. That heat is then trapped by several known gases.
These gases, mainly carbon-based molecules such as carbon monoxide, carbon dioxide and methane, preferentially absorb light at the infrared frequencies Earth emits. The concentration of these gases has been increasing throughout the Industrial Age, and the average global temperature has risen in response. These findings are well-supported by extensive research in the fields of physics, chemistry, geology, biology and meteorology.