I don't know what the reduction goal is, but a quick duckduckgoing found a number of 45 billion metric tons of CO2 added each year[1] as of 2017, which comes ou

I don't know what the reduction goal is, but a quick duckduckgoing found a number of 45 billion metric tons of CO2 added each year[1] as of 2017, which comes out to 12.2 billion metric tons of carbon (C is ~27% of CO2 by weight). So 4 million metric tons of carbon is about 0.03 percent of that total. [1] https://www.usatoday.com/story/news/world/2017/11/13/global-carbon-dioxide-emissions-reach-record-high/859659001/ https://www.usatoday.com/story/news/world/2017/11/13/global-...