Most of a latte’s carbon footprint is the milk

A conventionally grown, conventionally shipped latte works out at about 0.55 kg CO2e per serving. A black espresso pulled from the same beans works out at about 0.28 kg. The beans are identical. The difference is the milk.

Those figures come from a life-cycle assessment by Carmen Nab and Mark Maslin of UCL, published in 2020 in Geo: Geography and…