I just Googled population of the US and China, that's 326,766,748 (For US) vs 1,415,045,928 (For China).

So,

> China produces twice the amount of CO2 as the U.S. does

1,415,045,928 / 2 = 707,522,964

And

707,522,964 > 326,766,748

People in the US, please save some energy will you?