“1) Except [for] the fossil fuel borne CO2-emissions by the livestock industry (production, processing and commercialization of meat and milk) and except [for] some unique biosphere borne CO2-emissions, associated with land use change (e.g. deforestation), domestic animal husbandry is totally “climate neutral” (using a controversial terminology, only justified under the assumption of any measurable effect of anthropogenic GHG-emissions on global temperature). Why? Because all the CO2 emitted by forage digestion and respiration had previously been captured from the atmosphere through photosynthesis. Therefore, not a single CO2 molecule is added additionally to the atmosphere that had not been there before, recently.
2) This is also true for the methane produced by internal fermentation. Methane derives from organic substances originating from recent photosynthetic processes. And – as Richard Douthwaite from Ireland correctly points out in his letter (page 11) – methane molecules in the air are oxidized to CO2 and water at the end of their residence time in the atmosphere, closing the cycle. As a matter of fact the methane concentration has stabilized or even passed its peak just at the beginning of the new millennium. So obviously, just as much methane is oxidized in the atmosphere as is added to the air per unit of time. The resulting CO2 is available to be re-captured by photosynthesis. Therefore animal borne methane (how much its proportion ever may be among the total global methane emissions), just like CO2, forms part of a natural cycle, and not a single methane molecule is added additionally to the atmosphere by rumen fermentation that had not been there before, recently, unless livestock numbers increase.
3) The European satellite ENVISAT measured over a three years period the world wide close-to-the-surface-methane-concentrations. The average values are shown in figure 2 (source: University of Bremen <http://www.iup.uni-bremen.de:80/sciamachy/NIR_NADIR_WFM_DOAS/>). Not even international organizations like the IPCC or FAO seem to have taken notice of the fact, that even the humid tropical forests do obviously emit far more methane than grazing cattle. How can the big grazing areas of the world (Australia, Southern Latin America, South and East Africa, and Western United States with hundreds of millions of cattle) and even India with the highest cattle density worldwide show such low methane concentrations? Something wrong with the theory?
4) While it is banally true that all improvements in the efficiency of livestock production reduce herbage intake and along with it GHG emission per unit of product (meat or milk), the often cited figure of 18% of anthropogenic GHG emissions originating from domestic animal husbandry, as claimed by the highly controversial FAO-Report “Livestock’s Long Shadow” <http://www.virtualcentre.org/en/library/key_pub/longshad/A0701E00.htm> is clearly exaggerated. This document, that has done so much damage to the reputation of the livestock industry, was still proudly exposed at an international FAO symposium on the “Mitigation of GHG Emissions from Livestock”, held last month in Asunción, Paraguay:
a) How can the FAO claim that 25% of the domestic-livestock-borne CO2-equivalents originate from internal fermentation (methane), considering what has been outlined in the paragraphs 2 and 3? Just like CO2-emissions from the biosphere, animal borne methane emissions are part of a natural steady state equilibrium. So the 25% should be corrected to 0% as long as livestock numbers are constant.
b) How can the FAO claim that one third of the domestic animal borne CO2-equivalents come from deforestation (land use change), considering FAO yearbook numbers telling us that net deforestation on a world wide scale is almost zero? Close to 30% of the terrestrial surface are covered by forests and woodlands with very little change over the past 6 decades. So, once again just one scale pan of the balance has been taken into account. …
So definitely there is no need at all to be concerned about our livestock’s emissions of so called Greenhouse Gases! We won’t save the planet distorting ourselves in an effort to teach our cattle how to emit less methane. And we will not harm the planet when we go on with our cattle industry business as usual. Let’s just rebut unqualified attacks (unfortunately also originating from such prominent organizations as the FAO) on our livelihood! The sound arguments are ours.” From CCNet today. Profile of Dr. Glatzle here.