GLOBAL WARMING: COWS OR CARS? - MEAT: A Benign Extravagance - page 218

al respiration, G&A claim, is responsible for more CO 2 emissions than all the rest of the
FAO's 18 per cent, effectively doubling the amount of CO 2 attributable to livestock:
Livestock (like automobiles) are a human invention and convenience, not part of
pre-human times, and a molecule of CO 2 exhaled by livestock is no more natural than
one from an auto tailpipe. Moreover, while over time an equilibrium of CO 2 may ex-
ist between the amount photosynthesized by plants that equilibrium has never been
static. Today tens of billions more livestock are exhaling more CO 2 than in pre-in-
dustrial days, while earth's photosynthetic capacity (its capacity to keep carbon out of
the atmosphere by absorbing it in plant mass) has declined sharply as forest has been
cleared.
While there is little point in pursuing semantic arguments about the relative 'naturalness'
of photosynthesis and fossil fuels, the last sentence requires scrutiny. First of all, the tens
of billions of extra livestock, where do they come from? If there are more of them in the
world today than there were 200 years ago, that has to be because there is more of the kind
of vegetation they like to eat, both through the replacement of relatively inedible forests by
edible grassland, and through the increased luxuriance of vegetation thanks to additional
inputs of nitrogen, phosphate and water. There is no other way these animals can absorb
the carbon that they exhale. The process is neutral and short term: animals eat and exhale
every day, and plants go on absorbing carbon throughout most of the year.
That leaves us with G&A's assertion that the equilibrium has been disturbed as a result
of the decline in photosynthetic capacity caused by forest clearance. Forests photosynthes-
ize carbon, and since much of this carbon is not eaten by animals, instead it is stored in
the trees, and released over a longer time scale, when the forest is burnt or the trees rot.
The clearance of forests releases this carbon prematurely into the atmosphere, causing an
increase in CO 2 levels in the atmosphere. All this we know already. But carbon release
through deforestation caused by livestock is already accounted for by the FAO: by adding
their figure for livestock respiration to the FAO's figure for livestock-induced deforesta-
tion, G&A are double counting - clocking up carbon at one part of its cycle as it comes
out of an animals' lungs to enter the atmosphere, and a second time when it remains in the
atmosphere because it fails to be sequestrated for a period of years in a forest that no longer
exists. As for deforestation that is carried out for other purposes than livestock, it is hard
to see what connection that could possibly have with animals whose CO 2 output is entirely
reliant on the photosynthesized CO 2 that they ingest.
G&A cite only one source to back up their calculations about animal respiration - Alan
Calverd's article in Physics World . 81 He is their only source because, in their words, 'Cal-
verd's estimate is the only original estimate of its type'. They do not inform their readers,