Scientists project the temperatures of the future.
New climate research shows how the U.S. would experience warmer temperatures in the coming century as concentrations of the greenhouse gas carbon dioxide increase in the atmosphere. The research was conducted for the National Climate Assessment, an effort by the U.S. Global Change Research Program to study and prepare for climate change. In the first scenario, in which carbon dioxide emissions level off at about 550 parts per million (ppm) toward the end of the century, the average temperature of the continental U.S. would increase 4.5 degrees Fahrenheit by the year 2100. In the second scenario, in which carbon dioxide emissions rise to about 800 ppm (roughly double the 2013 level), temperatures would be, on average, 8 degrees Fahrenheit hotter than they were at the end of the 20th century. Watch the videos to see how each scenario give rise to warmer temperatures across the country.