Background: The goal of this activity is to debunk the following statements of the article. "From 2009 to 2050 global population is projected to increase by 36% (ref. 10). When combined with the projected 32% increase in per capita emissions from income-dependent global dietary shifts, the net effect is an estimated 80% increase in global GHG emissions from food production (from 2.27 to 4.1 Gt yr21 of CO2-Ceq).This increase of 1.8 Gt yr21 is equivalent to total 2010 global transportation emissions."

The Question: How much was 2.27 Gt of CO₂-Ceq. in relation to global emission circa 2010?

To find out global emssion of GHG expressed in CO₂-eq., let's visit this World Bank website. Total Emission in 2010 was approximately 50,000 Tg or 55 Gt (gigatonnes)

The top one (Diet and GHG) presents in a schematic way the results presented by Tilman and Clark to illustrate the emission 'savings' that would occur between 2009 an 2050 would move from the income-dependent diet to the Mediterranean diet, the Pescatarian diet and the vegetarian diet.

This slide shows the relative emissions of the main greenhouse gases (carbon dioxide, methane, nitrous oxide and a few others) from different sectors of the world economy according to a study of the World Resource Institute. Lets' assume that these proportion have remained unchanged since then.