Scientists' Explanation for Investigation 2

Concentration of Carbon Dioxide Since the Industrial Revolution

factory CO2 is a naturally occurring gas and an important part of Earth’s carbon cycle. Prior to the Industrial Revolution (1750’s), CO2 concentrations in our atmosphere were approximately 280 ppm. However, with the onset of the Industrial Revolution, humans began to contribute to CO2 concentrations being emitted to the atmosphere through the combustion of fossil fuels. As populations continued to grow, so did our use of fossil fuels. This accelerated use has caused CO2 concentrations to increase exponentially over the last century and we have recently measured readings of up to 400 ppm.