The New Scientist February 10, 2009
Eating less meat could cut climate costs
By Jim Giles
Cutting back on beefburgers and bacon could wipe $20 trillion off the cost
of fighting climate change. That's the dramatic conclusion of a study that
totted up the economic costs of modern meat-heavy diets.
The researchers involved say that reducing our intake of beef and pork would
lead to the creation of a huge new carbon sink, as vegetation would thrive
on unused farmland.
The model takes into account farmland that is used to grow extra food to
make up for the lost meat, but that requires less area, so some will be
abandoned. Millions of tonnes of methane, a potent greenhouse gas, would
also be saved every year due to reduced emissions from farms.
These impacts would lessen the need for expensive carbon-saving
technologies, such as "clean coal" power plants, and so save huge sums, say
Elke Stehfest of the Netherlands Environmental Assessment Agency and
colleagues.
Flatulent feeders
Climate-change experts have warned of the high carbon cost of meat for
several years.
Beef is particularly damaging. Methane, a potent greenhouse gas, is released
from flatulent cows and by manure as it decays. Furthermore, to produce a
kilogram of beef (2.2 pounds), farmers also have to feed a cow 15 kg of
grain and 30 kg of forage. Grain requires fertiliser, which is energy
intensive to produce.
Stehfest has now weighed the economic impact of beef and other meats against
the cost of stabilising carbon dioxide levels at 450 parts per million - a
level that some scientists say is needed to help prevent dangerous droughts
and sea level rises.
If eating habits do not change, Stehfest estimates that emissions would have
to be cut by two-thirds by 2050, which is likely to cost around $40
trillion.
If, however, the global population shifted to a low-meat diet - defined as
70 grams of beef and 325 grams of chicken and eggs per week - around 15
million square kilometres of farmland would be freed up. Vegetation growing
on this land would mop up carbon dioxide. It could alternatively be used to
grow bioenergy crops, which would displace fossil fuels.
Supermarket labels
Greenhouse gas emissions would also fall by 10% due to the drop in livestock
numbers, she calculates. Together, these impacts would halve the costs of
dealing with climate change by 2050.
To help consumers, the environmental cost of meat, in terms of carbon
emissions per portion, could also be included in the purchase price, says
Stehfest.
The costs sound about right, says Raymond Desjardins of Agriculture and
Agri-Food Canada. However, it may be unfair to compare future farms to
current ones, he adds.
Journal reference: Climatic Change (DOI: 10.1007/s10584-008-9534-6)