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KICK THE HABIT
THE PROBLEM
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intensive agriculture, and for transporting animals and crops from farm to
market. But the main GHGs emitted in agriculture are methane and nitrous
oxide, which underlines the need to become climate and not just carbon-
neutral. This is mainly due to meat production.
Cattle, water buffalo, sheep and other ruminants are animals with a spe-
cial stomach that allows them to digest tough plant material. Digestion
produces methane, which the animals get rid of by releasing it at either
end. Nitrous oxide release is mostly linked to the use of artificial nitrate
fertilizers to improve yields. Nitrogen fertilizer in particular is extremely
fossil fuel-intensive, requiring 1.5 tonnes of oil equivalents to make 1 tonne
of fertilizer.
A 2006 study of the impacts of the
food production chain
across the Euro-
pean Union found it accounted for 31 per cent of all EU GHG emissions.
Land use change and deforestation
Another important part of the CO
2
in the atmosphere comes from chang-
es in land use, responsible for almost 20 per cent of atmospheric carbon.
Trees and other plants remove carbon from the atmosphere in the process
of growing. When they decay or are burnt, much of this stored carbon es-
capes back into the atmosphere.
Deforestation also causes the release of the carbon stored in the soil (as
does ploughing), and if the forest is not restored afterwards the land will
store much less CO
2
.
If you do a life-cycle analysis of the food chain you must factor in agricultural
production, manufacturing, refrigeration, transport, packaging, retail, home stor-
age, cooking and waste disposal. Different foods cause impacts at different stages.
Potatoes, chickpeas and tea leaves, for example, need fewer greenhouse gases to
grow than they do to cook – baking a potato in an oven, boiling chickpeas for an
hour till soft, or switching the kettle on for tea all consume significant amounts of
energy. For frozen vegetables refrigeration is the key emission stage. Considering all
these factors and obtaining all the necessary information to do so may be a difficult
task, therefore doing a qualitative assessment can sometimes be a good alternative
and the more practical solution.