Omissions of Emissions: A Critical Climate Change Issue

It is difficult to overstate the seriousness of our current predicament on climate change. Despite the gravity of our circumstances, most groups campaigning for meaningful action ignore or overlook the critical issue of animal agriculture.

In a recent article, I discussed the fact that the Greens political party in Australia generally ignores the issue. In this article, I consider  the manner in which Australia’s greenhouse gas accounts under-report its impact.

The under-reporting has occurred because relevant factors are:

(a) omitted entirely from official figures, e.g. tropospheric ozone;

(b) classified under different headings, e.g. livestock-related land clearing reported under “land use, land use change and forestry”;

(c) considered but with conservative calculations, e.g. methane’s impact based on a 100-year, rather than 20-year, “global warming potential”.

The basis of reporting is generally in line with international practice, such as the Kyoto Protocol, and is valid in many respects. However, a critical problem is that it understates the shorter-term impact of animal agriculture, which is crucial if we are to have any chance of avoiding runaway climate change.

The mis-allocation of emissions sources also creates difficulties in determining the most efficient and effective mitigation measures.

Global Warming Potential

The emissions of different gases can be aggregated by converting them to carbon dioxide equivalents (CO2-e). They are converted by multiplying the mass of emissions by the appropriate “global warming potentials” (GWPs). GWPs represent the relative warming effect of a unit mass of the gas when compared with the same mass of CO2 over a specific period.

A 20-year “global warming potential” (GWP) for methane may be more valid than the 100-year figure used by the Department of Climate Change and Energy Efficiency and most other reporting bodies. That is because methane, a critical factor in livestock’s greenhouse effects, generally breaks down in the atmosphere in 9–12 years.  Accordingly, a 100-year GWP (which shows the average impact over a period of 100 years) greatly understates its shorter term impact.

For methane, the GWPs used by the UN’s Intergovernmental Panel on Climate Change (IPCC) are 21 for 100 years and 72 for 20 years. The UN Food & Agriculture Organization used a GWP of 23 for the 100 years in its 2006 “Livestock’s Long Shadow” report. NASA’s Goddard Institute for Space Studies estimates GWPs for methane of up to 33 for 100 years and up to 105 for 20 years.

Although methane may have a shorter life than carbon dioxide (which remains in the atmosphere for many hundreds of years), its impact can be long-term if it contributes to us reaching tipping points that result in positive feedback loops with potentially irreversible and catastrophic consequences. On the positive side, the relatively short-term nature of methane’s impact means that action on livestock production can be one of the most effective steps available to us in dealing with climate change.

Examples of under-reporting

The under-reporting of animal agriculture’s impact in Australia’s official reporting can be illustrated through two examples.

Example 1

An example of under-reporting was Australia’s National Greenhouse Inventory for 2008, which indicated that electricity generation represented 37 per cent of Australia’s emissions, compared to 10.7 per cent for livestock.

The report indicated that livestock’s emissions were 59 mt. The livestock figure was based solely on enteric fermentation (which causes methane to be released, primarily through belching) and manure management (which releases methane and nitrous oxide).

Adding emissions from livestock-related deforestation and savanna burning increases livestock’s emissions to 106 mt or 17.8% of the revised total.

Using that figure and applying a 20-year GWP to all methane emissions, the final percentage increases to 29.6%.

Here’s the comparison from my presentation “Solar or Soy: Which is better for the planet?“, with the original chart as background [1]:

Alternative measures of livestock’s contribution to emissions

The comparisons allow for the following assumptions:

• 85.1% of forest clearing was for livestock grazing [2]; and
• 56.9% of savanna burning was for livestock [3].

In respect of the first assumption, it is helpful to note that the National Greenhouse Gas Inventory’s land use change estimate for 2008 includes emissions and removals from all forest lands cleared that year as well as ongoing emissions from the loss of biomass and soil carbon on lands cleared over the previous twenty years. However, it does not allow for ongoing loss of carbon sequestration relating to the loss of vegetation.

The problem of under-reporting has also occurred in subsequent inventories.

Example 2

In the “Solar or Soy” presentation, I also referred briefly to other non-CO2 climate forcing agents, such as tropospheric (or ground level) ozone and black carbon, and the role of livestock in their formation.

Those and other factors were discussed in an interview on radio station 3CR’s “Freedom of Species“ program with Gerard Wedderburn-Bisshop, Executive Director of the World Preservation Foundation, on 7th October, 2012. Gerard is a former principal scientist with the Queensland Department of Environment and Resources Management Remote Sensing Centre. He was interviewed primarily in his capacity as a researcher on the Land Use Plan being prepared by climate change campaign group Beyond Zero Emissions (BZE) in conjunction with the University of Melbourne’s Melbourne Energy Institute and Melbourne Sustainable Society Institute.

In the interview, Gerard also said that 64% of the continent is used for livestock grazing. He indicated that BZE’s land use plan, due for release during 2013, is expected to indicate that animal agriculture is responsible for around 50% of Australia’s greenhouse gas emissions. The plan will not account for the role of black carbon (soot) due to a lack of reliable data for Australia. However, black carbon generated by animal agriculture globally plays a significant role in global warming.

Additional factors considered by BZE relate to deforestation, grassland emissions and savanna burning, including the role of tropospheric ozone.

Tropospheric ozone is formed through a series of chemical reactions involving nitrogen oxide, methane, carbon monoxide and other non-methane volatile organic compounds (VOCs). It is the third most prevalent greenhouse gas after carbon dioxide and methane (not allowing for water vapour). Major sources of carbon monoxide are agricultural waste burning, savanna burning and deforestation. Livestock grazing is one of the major drivers of deforestation and savannah burning.

To put the savanna burning into context, the 2009 Black Saturday bushfires in the state of Victoria burnt around 4,500 hectares.  In comparison, each year in northern Australia where 70% of our cattle graze, we burn 100 times that area across the tropical savanna. The savanna covers around 1.9 million square kilometres across northern Australia, which is around one-quarter of the nation’s land mass. The savanna vegetation is burnt primarily to prevent new tree growth and to stimulate the growth of high-protein green grass.

Here is an image from NASA depicting the extent of burning over a ten-day period in July-August, 2012:

Extract of MODIS Fire Map 29 Jul – 07 Aug 2012 from NASA Earth Data.

NASA has commented on the MODIS fire maps [4]:

“Each of these fire maps accumulates the locations of the fires detected by MODIS on board the Terra and Aqua satellites over a 10-day period. Each colored dot indicates a location where MODIS detected at least one fire during the compositing period. Color ranges from red where the fire count is low to yellow where number of fires is large. The compositing periods are referenced by their start and end dates (julian day). The duration of each compositing period was set to 10 days.”

BZE has also attributed relevant grassland emissions, including carbon dioxide, methane and nitrous oxide, to livestock. In the Freedom of Species interview, Gerard described the “fence line effect” in northern Australia, whereby bare ground will often exist on one side of a fence, while on the other there is knee-high native grass. The bare side will generally be owned by a pastoral company seeking to maximise its financial return. It will have increased stocking rates during times of favourable rainfall, then taken too long to reduce those rates during drought. The land becomes degraded, and carbon stores are significantly depleted.

An Alternative Approach

The northern and southern Guinea Savannas in Africa have also been adversely affected by livestock grazing.

As an example of an alternative approach to livestock in Africa, Gerard Wedderburn-Bisshop discussed the Kenya Hunger Halt program, administered by the World Food Program. Under the program, people have been taught to grow alternatives such as root crops.  The Maasai, traditional herders, have been converting to the program, growing nutritious crops and thriving.

What is possible in Australia? Forests are robust and will often regrow if given the opportunity. With sound management, it would be possible to remove livestock from huge tracts of land, and rely on significantly more efficient plant sources of nutrition.

Additional Comments

The World Preservation Foundation has cited information from German consumer protection organisation, Foodwatch, to report (with my underlines): ” . . . shifting from a conventional diet, including meat and dairy, to a conventionally-raised vegan diet would reduce emissions by 87 percent, while shifting to an organic diet including meat and dairy would only reduce emissions by 8 percent. By contrast, a 100 percent organic vegan diet would reduce emissions by 94 percent.”

Conclusion

Addressing the issue of animal agriculture would represent a relatively low-cost solution to critical aspects of the climate change crisis. We must not avoid the issue simply for the sake of satisfying those who are unwilling to change entrenched practices.

References:

[1] Dept of Climate Change & Energy Efficiency, National Greenhouse Inventory 2008, Fig. 15, p. 15. Livestock’s share of deforestation and savanna burning derived references [2] and [3].