Today, world leaders are meeting in Paris to discuss climate change at the COP21 conference. They are going to be discussing many issues around climate change from how to lower emissions to how to deal with rising sea levels. It is up to every country to change how their policies to be more sustainable and the wealthy countries that made their riches by exploiting the environment need to do even more. How then, do they decide what to do and based on what information?
The CBC is doing a series of investigations into issues and the like related to climate change that people may still be unclear on. One of their first articles is about how CO2 is measured.
When we measure carbon dioxide, can we tell how much came from burning fossil fuels?
Yes. The carbon in carbon dioxide comes in different forms called isotopes, namely carbon-12, carbon-13 and carbon-14. Levels of each vary depending on the source of the carbon dioxide, says Doug Worthy, study lead for Environment Canada’s greenhouse gas observational program.
Natural gas, coal and oil each also have distinct signatures for carbon-13, Worthy said.
Meanwhile, higher levels of carbon-14 mean that carbon dioxide sample is mostly from natural sources, such as plants. Lower levels mean it’s mostly from burning fossil fuels.