Friday, May 9, 2008

Feedlot cows produce more methane than pasture cows

As more researchers work to understand where ghg emissions occur in ag practices, we can begin to parse growing practices to determine which have a lower carbon footprint.

Environmental Health Perspectives posted recent research, Global Farm Animal Production and Global Warming: Impacting and Mitigating Climate Change, that does some of this parsing by combining the results of various related studies.

Here are some emerging facts from that article:
  1. "Animal agriculture sector accounts for approximately 9% of total CO2 emissions, which are primarily the result of fertilizer production for feed crops, on-farm energy expenditures, feed transport, animal product processing and transport, and land use changes (Steinfeld et al. 2006)."
  2. "Burning fossil fuels to produce fertilizers for feed crops may emit 41 million metric tons of CO2 per year (Steinfeld et al. 2006)."
  3. " Farm animals and animal production facilities cover one-third of the planet's land surface, using more than two-thirds of all available agricultural land including the land used to grow feed crops (Haan et al. 1997). "
  4. "Typically, cattle confined in feedlots or in intensive confinement dairy operations are fed an unnatural diet of concentrated high-protein feed consisting of corn and soybeans. Although cattle may gain weight rapidly when fed this diet (Pollan 2002), it can cause a range of illnesses (Smith 1998). This diet may also lead to increased methane emissions."
  5. And this: "The standard diet fed to beef cattle confined in feedlots contributes to manure with a "high methane producing capacity" (U.S. EPA 1998). In contrast, cattle raised on pasture, eating a more natural, low-energy diet composed of grasses and other forages, produce manure with about half of the potential to generate methane (U.S. EPA 1998)."
So feedlot cattle appear to produce twice the methane as pasture due to the diet. I assume this does not include the any methane from fertilizer or feed growing practices.

The first response seems obvious: eat less meat. The counterpoint is that we need protein. We can of course grow more pasture beef, but at current consumption habits we would have to expand land use for cattle quite significantly if we consume meat at current levels. Also, as health efforts (partially) succeed in getting us to reduce our red meat consumption in this country, as economic progress grows in developing nations, particularly China and India, meat consumption increases potentially negating any ghg reduction we have accomplished.

Ugh. So what can we do?

Since the climate is a global issue the pathway forward needs to incorporate global, national, and local concerns:
  1. Reduce feedlot cattle consumption everywhere.
  2. Increase the production of pasture beef.
    1. Which also decentralizes manure production and reduces the necessity of using fossil fuels to create fertilizers, and then transport them to buyers.
  3. Generate large consumer awareness programs in developing nations that as they turn their diets towards more red meat consumption that they request pasture beef.
    1. Other research shows that pasture beef has more omega 3 fatty acids than feedlot beef (will get source).
  4. Encourage trade policies that incentivize the production of low carbon meat.

Secondary source (primary sources in brackets, available in article): Koneswaran G and Nierenberg D, Global Farm Animal Production and Global Warming: Impacting and Mitigating Climate Change, Environmental Health Perspectives Volume 116, Number 5, May 2008,

Wednesday, February 20, 2008

Shipping emisssions recalculated

The UK Guardian ran a story last week entitled "True scale of CO2 emissions from shipping revealed: Leaked UN report says pollution three times higher than previously thought". The story is based on a report leaked from the UN to the Guardian that "calculates that annual emissions from the world's merchant fleet have already reached 1.12bn tonnes of CO, or nearly 4.5% of all global emissions of the main greenhouse gas." This number, 1.12 bn tons, is almost three times higher than previous estimates of a maximum 400 tons.

The report also mentions these points:
  • " CO₂emissions are set to rise by a further 30% by 2020."
  • " Other pollutants from shipping are rising even faster than CO₂emissions. Sulphur and soot emissions, which give rise to lung cancers, acid rain and respiratory problems are expected to rise more than 30% over the next 12 years."
  • " A recent peer-reviewed study of shipping emissions found world shipping led directly to 60,000 deaths a year."
Does this mean that ocean transport is not the preferred shipping method with regards to carbon footprint? Doubtful, but it may take some pressure off of the concerns around air shipments which the reports.

The best metric is still around volume or weight measurement. How much cargo is shipped that generates 1.12 billion tons of carbon for ships? How much cargo is shipped that generates the 325 million tons of airborn-shipping carbon?

Source: John Vidal, "True scale of CO2 emissions from shipping revealed, The Guardian, Wednesday February 13 2008, viewed online Feb. 20, 2008,

Wednesday, February 6, 2008

Economics of Buying Local, Part 1

Buying local has caught on around the country. Good for people, good for communities, good for health, good for farmers, good for ag land preservation, good for air, land, water, climate .... The beat goes on.

But is it good for the economy?

Separating out the economic return of growing local food for local consumption is gaining momentum as more governments and communities measure the economic return of going local.

New Jersey is one state that has measured such efforts. The state supports a Jersey Fresh program with an annual expenditure from state funds. From the 2004 NJ Agriculture Annual Report comes this fact:

Jersey Fresh Economic Impact – Using federal funds, a study was conducted to determine the economic impact of the Jersey Fresh Promotional Program. The study showed that each dollar spent on the Jersey Fresh program increased farm revenues by $31.54. That increase boosted farm-related businesses by an additional $22.95 of sales in agricultural support industries. In total, each dollar spent on Jersey Fresh promotion resulted in $54.49 of increased economic output in the State.

With a current budget for Jersey Fresh being about $800,000, this means an increase in farm revenues of $25.2 million, and a total increase in economic output for the state of $43.6 million.

Pretty good return.

Source: New Jersey Agriculture 2004 Annual Report, Agricultural Statistics, New Jersey Department of Agriculture / National Agricultural Statistics Service, USDA,

Tuesday, January 29, 2008

Ethanol and E Coli

New reports are emerging around a concern that the increase in ethanol production is fueling an increase in E. coli contamination. The connection is distiller's grain, a byproduct of ethanol production, that is becoming a cheap source of food for cattle.

As reported in the Des Moines Register on Jan 27, 2008: "Studies at two universities suggest that feeding cattle a byproduct of ethanol production known as distillers grains may increase levels of a deadly form of E. coli bacteria.

"Concerned about those findings, U.S. Department of Agriculture scientists have recently put 300 cattle on a diet of distillers grains and are testing them regularly for the bacteria. Results won't be known until later this year."1

The article continues to say that "Researchers at Kansas State University noticed the possible E. coli connection to distillers grains in 2005. A second study found a twofold increase in E. coli levels in cattle fed the product compared with those that ate only corn. Research at the University of Nebraska showed mixed results. Cattle fed a diet comprising 10 percent to 30 percent distillers grains actually had lower rates of E. coli than cattle on a diet of all corn. But cattle fed 40 percent to 50 percent distillers grains showed higher E. coli rates.

"That would suggest that there was something about these distillers grains diets that influenced the ability of these cattle to shed E. coli," said David Smith, one of the scientists who worked on the Nebraska research."2

Richard Raymond, the U.S. Department of Agriculture's undersecretary for food safety, was referenced as saying "the government had no intention of restricting the use of distillers grains even if the E. coli link is confirmed, and would instead leave it to the industry to decide how to address the issue. One possibility, he said, is to vaccinate cattle."3

This is an ironic twist to progressive policy solutions and shows that we are indeed in a new world needing new solutions for new problems. By increasing biofuels we are increasing the economics of 'factory farms'. "Closing the loop", or turning a waste in to a product, has meant that in ethanol production wet grain mash is being reused as a feed supply for cattle, thereby lowering the production costs of cattle and increasing the economic returns of Confined Animal Feeding Operations (CAFOs, a.k.a factory farms). As well, a wet grain is more energy efficient since you do not use additional energy to dry the grain after ethanol production, which means the net energy balance of corn based ethanol is better with wet distillers grain than dried grain.

As well, recent federal legislation encourages the expansion of ethanol production. This will mean an increase in distiller's grain. Will it mean an increase in E. coli as well?

Makes the stomach turn just thinking about it.

1) Philip Brasher, "Scientists study possible link between ethanol byproduct and E. coli", Des Moines Register, January 27, 2008,
2) Ibid.

3) A quote from same article, not exact quote from Raymond.