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On diet, climate change and water use


Cattle
Photo credit.

The foods we eat are a contributing factor to climate change.


The Guardian has reported, “Emissions from livestock, largely from burping cows and sheep and their manure, currently make up almost 15% of global emissions. Beef and dairy alone make up 65% of all livestock emissions. …[A Chatham House think-tank] report builds on recent scientific studies which show that soaring meat demand in China and elsewhere could tip the world’s climate into chaos.” The article highlights, “Meat consumption is on track to rise 75% by 2050, and dairy 65%, compared with 40% for cereals. …Two recent peer-reviewed studies calculated that, without severe cuts in this trend, agricultural emissions will take up the entire world’s carbon budget by 2050, with livestock a major contributor.”

In 2009, Scientific American reported, “[A 2006 report by the United Nations Food and Agriculture Organization] found that current production levels of meat contribute between 14 and 22 percent of the 36 billion tons of ‘CO2-equivalent’ greenhouse gases the world produces every year.”

In 2010, a report by the International Panel for Sustainable Resource Management found that agriculture accounts for 70 per cent of global freshwater consumption and 38 per cent of total land use, and is a major source of greenhouse gases, phosphorus and nitrogen pollution. Frances Moore Lappe adds, “Just as climate change is making water more precious, livestock production is using ever more of it. First note that nearly 70 percent of freshwater used by humans goes into irrigation, and much of it is used on crops and pasture for livestock–the big water guzzlers. In drought-plagued California, for example, meat and dairy account for almost half of the state’s entire water footprint.” The displacement of water is also a major contributing factor to climate change.

In 2012, the United Nations Environment Program stated, “Most studies attribute 10-35 per cent of all global GHG emissions to agriculture (Denman et al. 2007, EPA 2006, McMichael 2007, Stern 2006). Large differences are mainly based on the exclusion or inclusion of emissions due to deforestation and land use change. …Scientists agree that in order to keep GHG emissions to 2000 levels the projected 9 billion inhabitants of the world (in 2050) need to each consume no more than 70-90 grams (McMichael et al. 2007, Barclay 2011) of meat per day. To meet this target, substantial reductions in meat consumption in developed countries and constrained growth in demand in developing ones would be required.”

And in 2014 report from the United Nations Intergovernmental Panel on Climate Change noted that dietary change can “substantially lower” emissions.

The US Environmental Protection Agency says that the global sources of greenhouse gas emissions by economic sector are as follows:


  • 25 per cent – the burning of coal, natural gas, and oil for electricity and heat is the largest single source of global greenhouse gas emissions

  • 24 per cent – greenhouse gas emissions from agriculture (cultivation of crops and livestock) and deforestation

  • 21 per cent – fossil fuels burned on-site at facilities for energy

  • 14 per cent – fossil fuels burned for road, rail, air, and marine transportation, with 95 per cent of this related to petroleum-based fuels, largely gasoline and diesel

  • 10 per cent – emissions from the energy sector which are not directly associated with electricity or heat production, such as fuel extraction, refining, processing, and transportation

  • 6 per cent – the on-site energy generation and burning fuels for heat in buildings or cooking in homes

Both systemic change (including challenging tar sands export pipelines and so-called ‘free trade’ agreements, like the Canada-European Union Comprehensive Economic and Trade Agreement, that promote increased beef exports and water displacement) and individual action in all of these areas is needed to address climate change.

Further reading
UN report says shift to vegetable-based diets needed to reduce climate change (June 2, 2010)
CETA promotes virtual water exports (Feb. 23, 2014)