translation.en: And not only that, when you cut emissions, you don't cut concentrations, because concentrations, the amount of CO2 in the air, is the sum of emissions over time.
translation.zh: 不仅如此，当你减少排量的时候，你并没有减少浓度。 因为浓度的定义是空气中CO2的总量， 是长期排放的总和。