Bangladesh Dairy Study: Farm-Specific Data Cuts Milk Carbon Footprint Estimate by 27%

Researchers at UConn and Bangladesh Agricultural University used five years of farm-level data from a Bangladeshi dairy herd to recalculate the carbon footprint of milk. Applying IPCC Tier 2 methods instead of Tier 1 regional defaults lowered the estimated footprint by 27%, to 5.18 kg per kg of milk. Enteric fermentation was the largest source at 48%, followed by feed production at 24% and manure at 20%. The findings appear in the Journal of Dairy Science. Most of the gap with U.S. and European dairy comes down to accounting. Bangladeshi farms raise cattle for both milk and meat, so allocating all emissions to milk makes it look far worse. The team also found that raising milk output per cow, which climbed 63% over the study period, cut the per-kg footprint by 37%. For anyone working on low-carbon food systems, the lesson is that better data and better productivity can matter as much as new mitigation tech.