Roast lamb and roast beef are classic Australian dinners, and both are, in their own right, quite delicious. In recent years, however, there have been a growing number of articles in the popular press examining the environmental impact of eating meat. Which got me thinking: is it more environmentally friendly to eat lamb or beef? And how do these meats stack up against the other ingredients that are commonly used in a roast?
The data presented in the graph below relates to the amount of water (in cubic metres) and CO2-equivalent emissions (in tonnes) required to produce one tonne of the selected ingredients in Australia. Lamb appears to be more environmentally friendly than beef, at least when evaluated in terms of water and carbon emissions. Nevertheless, both meats have a substantially greater impact on the environment than vegetables. So, next time you are making a roast, think about using lamb instead of beef and consider reducing the amount of meat that you use.
Notes:
- Yes, pumpkin and onions are essential elements of a roast, but I couldn’t find Australian water consumption figures for these vegetables.
- The Peters et al. (2010) paper provides several estimates of the CO2-e emissions associated with both beef and lamb production. The means of these estimates were used in the graph above.
- The CO2-e figures relate only to the production of the raw ingredient. Thus, the energy required to transport and prepare these ingredients is not considered.
- Maraseni et al. (2010) – An assessment of the greenhouse gas emissions from the Australian vegetables industry: Table 4
- Peters et al. (2010) – Red meat production in Australia: Life cycle assessment and comparison with overseas studies: Table 3
- Water footprint network – Water footprints of crop and livestock products (m3/ton) for some selected countries (1997-2001)
Discussions about mitigating the effects of climate change invariably lead to national comparisons of greenhouse gas emissions, and such comparisons reveal that China is the world’s largest emitter of CO2, followed closely by the USA. One of the problems associated with such comparisons, however, is that they fail to account for national differences in population. A fairer comparison would therefore be to examine per capita CO2 emissions.
The graph below contains the per capita CO2 emissions of various nations in 1990 and 2007. As the graph reveals, many nations throughout this period experienced dramatic growth in per capita CO2 emissions, and this growth was particularly evident in the Asia-Pacific region. It should be noted, however, that much of this growth took place off the back of low per capita CO2 emissions.
Juxtaposed with this growth was the small to moderate declines in per capita CO2 emissions throughout Western Europe and the former Soviet Union. Nevertheless, per capita CO2 emissions in many of these nations still remained high. If we are to take to heart Jefferson’s sentiment that ‘all men are created equal’, then we must move towards a future where everyone has the same right to emit the same (sustainable) amount of CO2.
Source:
- International Energy Agency: CO2 emissions from fuel combustion 2009 - pp. 89-91