We are confident that rising CO₂ levels are caused by the burning of fossil fuels because atmospheric CO₂ now has the same carbon isotope ratio as fossil fuels.

Question

Quizplus · Accepted Answer

The burning of fossil fuels releases carbon dioxide with a distinctive carbon isotope ratio. This ratio has been found in atmospheric CO₂ and can be used to trace its source back to fossil fuel burning.

We Are Confident That Rising CO₂ Levels Are Caused by the Burning