Meat Eaters Guide: Methodology - Environmental Working Group

Meat Eaters Guide: Methodology
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trailer truck.
• All food items are assumed to be produced and transported domestically, with the exception
of lamb and salmon, which are assumed to be imported and transported via ship a distance
equal to the average distance of the top two producing countries. Lamb production data is
domestic; our calculations assume that 50% is imported by ship from New Zealand and Australia.
• All food products are assumed to travel 2,253 km (1,500 miles) and by semi-trailer truck 161
km (100 miles) by single-unit truck to final retail establishment. 16
• For imported products (lamb, salmon, imported cheese), we estimate emissions for each item
using the average distance (in nautical miles) from the top two exporting countries.
• All transport modes are assumed to have 100 percent utilization (full use of the truck) and 100
percent backhaul (use of the return trip for hauling other freight).
Clearly, the actual distance traveled by different inputs will vary by region and production system. In
some cases, animals are trucked much farther than 300 km from where they are born to where they
are raised in confinement. The distance that food travels to its final destination will also vary. For the
purposes of this analysis, we selected a set of consistent assumptions based on general averages. In
order to provide a sense of the differential GHG impact of eating locally or regionally, our model calculated
GHGs of food that was transported either 2,253 km or 161 km (100 miles). Surprisingly, the actual
GHG differential between 2,253 km and 161 km is quite small. In the case of beef, eating a kilogram
of beef that travelled 161 versus 2,253 km only changes the GHG footprint by 0.28 kg CO 2 e per
kg of beef consumed – less than 1 percent of beef’s total emissions. The difference is much greater in
vegetables, where the overall footprint is much smaller. Buying locally can reduce the overall footprint
by as much as 20 percent for broccoli and 25 percent for tomatoes; local purchasing reduces meat’s
carbon footprint by just 1-3 percent. We also considered the GHGs associated with shipping products
such as cheese and lamb (about 50 percent of lamb is imported). Shipping adds 0.18 kg CO 2 e per kg
beef, but just 0.06 kg CO 2 e per kg of cheese.
c. Fertilizer and Pesticide Production
Fertilizer production is an energy-intensive process that relies primarily on natural gas. Pesticide
production is also energy intensive, relying primarily on the use of crude petroleum oils and/or natural
gas. CO 2 is generated from the energy used in production and in treating the resulting wastewater.
CleanMetrics based emission factors for fertilizer production on International Fertilizer Association
(IFA) publications. 17 Pesticide data were derived from the Encyclopedia of Pest Management.Water/
wastewater treatment data are from American Council for an Energy Efficient Economy (ACEEE) and
IPCC. Emissions associated with transportation of fertilizers and pesticides to the agricultural sites
are based on an assumption of 1,600 km by semi-trailer truck and 200 km by single-unit truck. 18
Environmental Working Group Meat Eaters Guide: Methodology 2011