A Ratio for the Relative Climate Change Impact of an Economic Activity

I propose a ratio for assessing the climate change impact of an economic activity as a function of global greenhouse gas emissions and annual gross world product. To construct a simple example, I consider only CO2 emissions and use the purchase and combustion of gasoline. I show that it has a ratio of 8.82:1 in the United States as of March 6, 2019 at a national average price of $2.44 per gallon. This means that in consideration of the direct impacts of gasoline’s combustion alone, gasoline would have to cost $21.50 per gallon in order to achieve a 1:1 ratio. Other applications of the ratio and its impact are discussed.