Livestock and Climate Change: What if the key actors in climate change are… cows, pigs, and chickens?



From ROBERT GOODLAND AND JEFF ANHANG
Worldwatch Institute
Thanks to RON EPSTEIN
Ukiah

Whenever the causes of climate change are discussed, fossil fuels top the list. Oil, natural gas, and especially coal are indeed major sources of human-caused emissions of carbon dioxide (CO2) and other greenhouse gases (GHGs). But we believe that the life cycle and supply chain of domesticated animals raised for food have been vastly underestimated as a source of GHGs, and in fact account for at least half of all human-caused GHGs. If this argument is right, it implies that replacing livestock products with better alternatives would be the best strategy for reversing climate change. In fact, this approach would have far more rapid effects on GHG emissions and their atmospheric concentrations—and thus on the rate the climate is warming—than actions to replace fossil fuels with renewable energy.

Livestock are already well-known to contribute to GHG emissions. Livestock’s Long Shadow, the widely-cited 2006 report by the United Nations Food and Agriculture Organization (FAO), estimates that 7,516 million metric tons per year of CO2 equivalents (CO2e), or 18 percent of annual worldwide GHG emissions, are attributable to cattle, buffalo, sheep, goats, camels, horses, pigs, and poultry. That amount would easily qualify livestock for a hard look indeed in the search for ways to address climate change. But our analysis shows that livestock and their byproducts actually account for at least 32,564million tons of CO2e per year, or 51 percent of annual worldwide GHG emissions.

Complete article available here
~~

One Comment

Discussion Forum on Livestock Emissions:
Alexander Ochs Dateline Copenhagen 2009-11-05

In an article in the November/December 2009 [PDF] edition of World Watch Magazine (“Livestock and Climate Change”), authors Robert Goodland and Jeff Anhang argue that livestock emissions have been severely underestimated. In their view, livestock and their byproducts account for at least 32.6 billion tons of carbon dioxide equivalent each year, or 51 percent of annual worldwide GHG emissions. Based on their analysis, Goodland and Anhang recommend a radical decrease in meat consumption in order to help slow climate change.

Goodland and Anhang’s numbers are far above those reported in a widely cited 2006 report, Livestock’s Long Shadow, by the United Nations Food and Agriculture Organization. It estimates that 18 percent of annual worldwide GHG emissions are attributable to cattle, buffalo, sheep, goats, camels, pigs, and poultry. “Livestock and Climate Change” has stirred intensive discussion in a number of fora. While some readers supported the authors’ assessment and recommendations, others disagreed with either or both.

We want to provide everyone who is interested in this important debate—experts or not—with an open forum for discussion. While the magazine’s masthead clearly states that “Opinions expressed in World Watch are those of the authors, and do not necessarily reflect the positions of the Worldwatch Institute,” scientific integrity and the search for viable sustainability solutions are the foundation of the Institute’s daily work.

We invite you to contribute to the discussion by commenting on the article here. The most constructive and compelling comments will also be printed in a future issue of World Watch. In addition, please check out our blog, Nourishing the Planet, where the Worldwatch food and agriculture team argues for a different, and in their view more effective, way to address mixed-crop livestock and sustainable food than the Goodland/ Anhang article recommends.
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15 Comments

1.
Jeff in Cincinnati, OH says:
November 5, 2009 at 9:45 pm

The biggest part of the problem is factory farms, mostly. Read ‘Righteous Porkchop’ http://bit.ly/1oJ66a. Diet has big impact on enteric emissions.
2.
Robert Goodland says:
November 6, 2009 at 2:36 pm

In “Livestock and Climate Change,” I and Jeff Anhang estimated that at least 51% of human-caused GHGs are attributable to the life cycle and supply chain of livestock products. We appreciate comments from readers showing us where our arguments could have been clearer.

One comment we’ve seen is that livestock respiration is not normally counted in GHG inventories, as livestock consume plant matter whose photosynthesis balances the respired carbon. In fact, we used carbon from livestock respiration as a proxy for carbon absorption foregone in land cleared for livestock and feed production. We did this because it enabled us to reference a published calculation, whereas we found no published calculation for carbon absorption foregone in land. To be careful not to double count, we estimated that a minimal “at least 4.2%” of global GHGs are attributable to carbon absorption foregone in land set aside for livestock and feed production. It should be obvious that the true number is much higher.

Therefore, to address this comment, we can replace the use of respiration as a proxy by restating our analysis as follows. Total foregone reduction attributable to livestock and feed production can be counted as the sum of the “at least 4.2%” of global GHGs that we previously assigned to foregone reduction plus the 13.2% of global GHGs that we assigned to livestock respiration. This way, the same total as we previously reached for respiration and land use – i.e., at least 17.4% of global GHGs – would be assigned to carbon reduction foregone in all the land cleared for livestock and feed production. This is a very conservative estimate.

We believe that counting foregone carbon reduction is analogous to the common, uncontroversial counting of foregone emissions in GHG assessments. Counting a foregone reduction of any magnitude is valid because it has exactly the same effect as an increase in emissions of the same magnitude. Moreover, carbon reduction available from land used for livestock and feed production is the only feasible way to absorb a significant amount of today’s atmospheric carbon in the near term. For those readers who have wondered where the “missing” carbon sink is to match all the GHGs we’ve counted, we would note that foregone carbon reductions involve a potential carbon sink rather than an actual carbon source.

Second, some readers have commented that our article should have included a re-calculation for non-livestock methane. In fact, the methane re-calculation in our article was built on an amount of livestock methane reported by the FAO. We haven’t yet found a figure for non-livestock methane that we are comfortable using in parallel with the FAO’s figure for livestock methane. Our article noted that further work on this topic was needed. At the same time, publication proceeded without an accurate figure for the total number of livestock worldwide. We discovered after publication that the FAO’s own statistical division reported 56 billion livestock worldwide in 2007. This is many more than the count in our article, and doubtless outweighs whatever the increase would be in non-livestock methane.

Third, some readers have commented that we failed to assess fully the health and environmental impacts of fake meats. In fact, a veggie burger can made by simply chopping and pressing whole legumes and vegetables, or it can be heavily processed. Our article includes whole grains and legumes as an option. But the key challenge is to help Western consumers transition away from a diet typically heavy in meat. Most people who have made such a transition have used fake meats to ease the process. Fake meats are easily marketable on a large scale in a short time frame, as appears necessary to reverse climate change. The inputs of grain and legumes required to produce them are a small fraction of those required to produce animal-based meats. So our proposal would stop today’s trend of increasing conversion of forest to livestock and feed production, as already-converted land would be more than enough to produce fake meats. Dietary and environmental improvements could and should still be pursued over time.
3.
Tuomas Mattila says:
November 9, 2009 at 7:39 am

Thank you for the thought provoker.
You might have an inconsistency in the counting of “biogenic” CO2, though. If you opt to count for the respiration of animals, you should also count the CO2 released by biofuels. And if you do that, there would be minimal benefits compared to coal, right? The Stern report follows the “normal procedure” of counting only fossil CO2.

If you think it the other way around (as you do in the comment above), that the climate impact of livestock is caused by not-reforesting, the same problems apply. If you use the areas saved from livestock to biomass production, the overall biomass would not increase, neither would the sequestration. (At least not immediately… after decades you would have a standing mature forest, which you could manage for biomass.)

Even if you remove the impact of potential biomass production (2.67 Gt) the overall impact of continuing animal product instead of quitting it remains considerable. So shoudn’t you either remove the foregone sequestration or the biofuels? “You can’t eat the cake and have it.”

All the best,
Tuomas
4.
Keith Akers says:
November 10, 2009 at 3:13 pm

David Steele of EarthSave Canada says in his blog on your article:

“What we really need to consider is not the absolute amount of CO2 breathed out by the farm animals but, instead, the amount by which that number exceeds what would be pumped out if the land now used to feed the farm animals was allowed to return to nature instead.”

What would your response to this be?

My suspicion is that the wild animals displaced are fairly small compared to the livestock biomass added (and thus GHG emissions). Humans harvest close to 100% of the edible crop to feed to livestock, but wild animals would not be nearly as efficient. Furthermore, wild plants have evolved over millions of years to be difficult for animals to eat, whereas humans have selected crops to maximize food yield. So without any particular facts or figures, my suspicion would be that the biomass of wild animals displaced is quite small relative to the biomass of the livestock added. Just some thoughts.

Keith
5.
Stephen R. Kaufman, M.D. says:
November 11, 2009 at 10:14 pm

I commend the authors of “Livestock and Climate Change” (LCC) for their thoughtful analyses. They make a strong case that the 18% figure of the 2006 FAO report “Livestock’s Long Shadow” (LLS) is too low, but I have some reservations about some aspects of the LCC analysis.

LCC argues that land currently used for grazing and growing animal feed is not being allowed to grow back into forests, and this constitutes GHG contribution by virtue of forgoing a means by which GHG could be reduced. It seems to me that it is inaccurate to count this as an ongoing source of GHG. As forest or other land is cleared for grazing, there is a net release of greenhouse gasses (primarily carbon). Subsequently, there develops a balance between carbon sequestered in plants grown for animal consumption and carbon released by the animals into the atmosphere on account of animal respiration. It seems that LCC charges the enterprise of animal agriculture annually for plant growth foregone due to animal agriculture, whereas it seems to me that a one-time charge as the land is cleared is more appropriate.

When calculating human-caused global warming due to animal agriculture, as best I can tell, LCC has not considered global warming from the plant-based agriculture that would replace the animal agriculture if people reduced their consumption of animal products. If people moved toward plant-based diets, they would generally reduce their carbon and other greenhouse gas footprint substantially. Nonetheless, land is cleared for plant foods that humans eat, and fossil fuels are used to grow, transport, store, and cook these plant foods (again, generally much less than animal-based foods).

LCC asserted that biofuels can yield 80% less GHGs per unit of energy than coal. I was surprised to read this, since it has been my understanding that both biofuels and coal generate most of their energy from carbon-carbon bonds. I wondered what sources would back this up. In addition, coal is often “dirtier” than biofuels, particularly in developing nations that don’t have strong environmental laws. Particulate matter released from burning coal tends to have a global cooling effect, though it is my understanding that these particles don’t have a long atmospheric half-life.

LCC noted LLS was based on data from 2002, and there has been a 12% increase in worldwide animal agriculture since that time. In arriving at the figure of 51% of total GHG emissions from animal agriculture, LCC evidently holds that total GHG emissions from other sources have not unchanged over this period. Is this a valid position?

I am hopeful that LCC’s authors or others can address these concerns.
6.
Jack Zhao says:
November 25, 2009 at 11:55 pm

Yes, the livestock is the main thing which we need to decrease, otherwise the doomsday will come soon.
7.
Brenda says:
December 10, 2009 at 9:59 am

Thank you World Watch for your courageous analysis and leadership on this matter.

If there were one message to drive home with world leaders and those meeting in Copenhagen, it would be that the thing to do right now, immediately, is to stop subsidizing animal production.

I have been noticing over since the UN report came out just how much money the government spends propping up these industries. The banks were not the first ones to get the massive bailouts. Just in the county where I live, the slaughterhouse was subsidized, the railroad (which is connected to the graneries where the get the feed to transport out to where the cows are) is subsidized, the land trust (which is mostly for ranching and dairy) is subsidized, the USDA indemnity insurance for crops and cows is subsidized. The research on animals to try to cure all the dread diseases that result from eating them is subsidized. The healthcare is subsidized. It’s endless.

And it is the taxpayers who ultimately foot the bill.

If you add it all up, the money we could save, the greenhouse gases we could cut, and the health problems we could prevent or reverse (you can read “The China Study” for more info on that), and all the money you can save from people not developing dread diseases from eating animals and not having to spend billions of dollars on research to treat totally preventable health problems, and not having to contribute to the enormous suffering of animals on farms and in laboratories all over the world, it really adds up.

So just stop subsidizing animal agricultrue ASAP and let’s see what happens. It certainly can’t hurt.
8.
Sue Michalsky says:
December 10, 2009 at 3:05 pm

While it appears that the calculations in LCC are quite complex, what the authors seem to lack is a basic understanding of agriculture. In addition to attributing the carbon reduction from land clearing to livestock and assuming the highly unlikely scenario that without livestock the land would not be converted to grain or legume production, there are a number of issues not addressed in the calculations.
1. A significant amount of grain and especially legume production does not meet human consumption standards. Without livestock to consume this supply, what do the authors suggest be done with this product and how would they calculate the GHG emissions from waste crops? How much extra land would have to be put in to crop production to provide profits to cover the financial loss to farmers of non-human grade crops? Perhaps the waste crops could go into biofuels? However, there are biofuel standards too. Or perhaps enough investment in GMOs so weather and pests will have less impact on the grade of crop?
2. Biofuels made from grains produce a byproduct that may be utilized by livestock. Again, without livestock to consume this byproduct, what happens to it? How would this waste be accounted for in GHG calculations? And how much less effective would that make biofuels?
3. Livestock producers in North America sell carbon credits on the carbon market for land converted from annual crops to perennial crops. That means the marketplace values the carbon sequestration potential of land that produces livestock. How do the LCC authors justify discounting this value?
4. There are millions of livestock produced on the Great Plains of North America and other natural grasslands around the world. These grasslands have evolved with grazing and support grazing in addition to ecological values. They have not been cleared and converted to annual crops, but they would be if they did not support livestock. There are many studies around the world that show that any change that tips the balance towards plant crop production as opposed to livestock production results in additional land being cleared of natural vegetation. A case in point is the recent increase in grain production for ethanol in the US. The world’s natural landscapes provide the best environmental protection; the best carbon sequestration, the best water retention, the best water quality, the best biodiversity etc. Many jurisdictions around the world pay livestock producers to retain natural habitat because there is an inherent comptability between the two. None of this is addressed in the LCC.

The simplistic assumption that ridding the world of livestock would solve our climate change problems is just that – too simplistic. A far more effective approach would be to target the livestock production techniques that contribute most to GHG emissions and other environmental degredation in an effort to reduce this type of production; while simultaneously promoting the livestock production techniques that result in carbon neutral or carbon sink scenarios.
9.
Robert Goodland says:
December 11, 2009 at 12:25 am

1. Jeff Anhang and I appreciate all the comments and questions from readers. We also appreciate the high volume of media coverage of our article in recent weeks. ***

2. The U.N. Food and Agriculture Organization invited me to participate in its expert consultation in Rome on December 2-4, 2009. My presentation to the consultation can be seen at http://www.wellfedworld.org/PDF/FAOConsult12-09.pdf.
***
3. To Tuomas Matilla, we would maintain that the benefits of biofuels over coal are as described in our article. Our article does not propose that the benefits from replacing livestock with biomass would be immediate, nor does it propose that more sequestration could coexist with biofuels. Yet we believe there would be benefits before decades passed. ***

4. To Keith Akers, we would say that indeed, all the numbers applicable to realistic scenarios of land use should be counted; and indeed, a key reason why livestock are introduced on any given plot of land is to raise many more than the number of wild animals that could be raised on that same amount of land. ***

5. To Stephen Kaufman, we’d say that a one-time charge does not suffice for carbon emissions from land cleared for livestock and feed production. That’s because on most such land, forest could regenerate. In such cases, there’d be not merely an equilibrium between carbon emitted by livestock and carbon absorbed by plants, but large amounts of carbon sequestered each year. In fact, in few areas does equilibrium exist. In most areas, soil emits carbon each year, with particularly high amounts in tropical areas. Plant-based products require much less land than meat and dairy products; so we believe we’ve indeed considered what you’ve suggested we did not consider. Our sources are listed on Worldwatch’s website, and they show that we did not use statistics for emissions from 2002. ***

6. To Brenda, we’d say we agree that subsidies for animal agriculture should be lifted. As our article proposes, we also believe that there is more to be done. ***

7. To Sue Michalsky, we’d say we agree that there are many topics unaddressed in our article. We think it is a stretch to say this means that we do not understand the missing topics. Indeed, we had to cut our article by more than half to meet the word limit for articles in World Watch. We are quite sure that our article nowhere proposes ridding the world of livestock. However, we believe that wherever crops are fed to livestock, they could instead be fed to humans directly. We agree that it makes sense to graze livestock where there would be little or no net emissions and forest cannot be regenerated. However, this would involve a small fraction of today’s worldwide livestock numbers, as no more than eight percent of meat in the world today is produced without feeding crops to livestock.
10.
Steve Rudman says:
December 11, 2009 at 4:38 pm

In an article titled “Don’t Blame Cows for Climate Change,” UC Davis professor Frank Mitlhoehner
says that “…leading authorities agree that, in the U.S., raising cattle and pigs for food accounts for about 3 percent of all greenhouse gas emissions, while transportation creates an estimated 26 percent.” See http://www.news.ucdavis.edu/search/news_detail.lasso?id=9336&fu=121109

His full analysis was published in the journal Advances in Agronomy.

Professor Mitlhoehner further “notes that “Livestock’s Long Shadow” produced its numbers for the livestock sector by adding up emissions from farm to table, including the gases produced by growing animal feed; animals’ digestive emissions; and processing meat and milk into foods. But its transportation analysis did not similarly add up emissions from well to wheel; instead, it considered only emissions from fossil fuels burned while driving.

“This lopsided ‘analysis’ is a classical apples-and-oranges analogy that truly confused the issue,” Mitloehner said.” [Quoted from the UC Davis research news article cited above.]

Any comments on Professor Mitloehner’s claims?
11.
Robert Goodland says:
December 17, 2009 at 1:03 am

Steve Rudman has asked a question that my co-author Jeff Anhang and I believe should be answered as follows. ***

It is unclear whether Professor Mitloehner has read our article “Livestock and Climate Change,” and if so then how he would react to it. But it seems fairly clear that Professor Mitloehner is unaware of the widely-accepted GHG protocol on how to count emissions in GHG inventories across all industries, described at http://www.ghgprotocol.org/. According to this protocol, emissions counted on the site of an industry should be attributed directly to that industry as Scope 1 emissions. Emissions from energy purchased offsite should be attributed directly to that industry as Scope 2 emissions. Other emissions are counted optionally, and are called Scope 3 emissions. ***

Most emissions counted in both “Livestock’s Long Shadow” and our “Livestock and Climate Change” would normally be considered as Scope 1 emissions. That’s because most emissions counted in both reports are attributable to feed production and to the physiology of livestock. Emissions attributable to the physiology of livestock are obviously Scope 1. In case it is less clear that emissions attributable to feed production are Scope 1: When assessing the livestock sector as a whole – rather than an individual livestock business – feed production would be considered an integral part of the livestock sector. Perhaps these emissions could arguably be considered as Scope 2, but certainly not as Scope 3. ***

Conversely, in the transportation sector, emissions from fossil fuels burned while driving would normally be considered as Scope 3. After all, almost none of the fuels burned in driving are purchased by any part of the transportation industry. So it would make sense if Professor Mitloehner proposed that comparing livestock and transportation industries requires attributing to the transportation industry all the emissions from steel production to car dealerships – as they are Scope 1 and Scope 2 – and perhaps require excluding Scope 3 emissions from fuels burned in driving. But then livestock wouldn’t seem as benign as he proposes. ***

Further, as explained earlier on this blog, it is essential to count emissions attributable to foregone carbon absorption on land set aside for livestock and feed production – as regenerating forest on such land is probably the only feasible way to absorb a large amount of today’s atmospheric carbon in the near term. Counting these emissions is a less-controversial alternative to counting emissions directly from livestock respiration. Either way, the amount of these emissions is very large; yet it seems that Professor Mitloehner has neglected to consider them, along with other emissions attributable to the life cycle and supply chain of livestock products both within and outside the U.S. Professor Mitloehner is remiss in considering livestock emissions only within U.S. borders, as livestock products and feed are global commodities – flown, shipped and trucked all over the world – and climate change is of course transboundary.
12.
Shanna Cheng says:
December 22, 2009 at 1:27 am

I visit here now and then to learn more about climate facts. Thank you! Thank you! I have learned a lot!
13.
Keith Akers says:
December 28, 2009 at 12:48 am

Hi all:

I have a comment to make on Sue Michalsky’s comment about biofuels. She says:

“2. Biofuels made from grains produce a byproduct that may be utilized by livestock. Again, without livestock to consume this byproduct, what happens to it? How would this waste be accounted for in GHG calculations? And how much less effective would that make biofuels?”

Of course Goodland and Anhang could respond correctly that they did not propose the complete elimination of livestock. But assuming we are talking about a vegan world, even then this is an extraordinarily small issue.

At the ASPO-USA conference in Houston in 2007, Dr. Kyriacos Zygourakis, of Rice University (chair of chemical and biomolecular engineering) gave a talk entitled “How Good is Our Bet on Biofuels?” I think you can hear the talk online at the ASPO-USA web site. His conclusions are roughly as follows: Pimentel and Patzek’s assessment of biofuels gives them an EROEI of about 0.75, others who count the livestock co-product give it an EROEI of 1.25. The difference in EROEI is roughly the energy “wasted” by eliminating livestock.

This is an initial ballpark estimate, because different forms of energy are involved with different GHG consequences, there are land use issues, and so forth. Others have said that corn ethanol actually contributes to global warming emissions, such as Tim Searchinger, a research scholar at Princeton University’s Woodrow Wilson School of Public and International Affairs who was the lead author of a study on this subject published in early 2008 in Science magazine.

The consensus appears to be that current biofuels (corn ethanol, etc.) are a colossal waste of time and money. If the best we could do for energy across the board was an EROEI of 1.25, the world would likely be reduced to an economic level roughly equivalent to that in medieval times: enough surplus energy to support kings, jesters, literate monks, and a few other things, but certainly not enough to support modern industrial society. The fact that corn ethanol continues to be subsidized (in “Our Choice” even Al Gore now thinks it’s a mistake) is yet another example of the triumph of politics over science.

Barring some revolutionary breakthrough in biofuels to increase EROEI (cellulosic, anyone?), which has been promised for a long time but seems perpetually in the research stage, I’d say that biofuels are a marginal issue here and that calculating the GHG consequences of eliminating this source of “productive” use of biofuel byproduct is vanishingly small.
14.
Chris Mentzel says:
January 1, 2010 at 2:00 pm

Thanks for your phenomenal work – here is an article I wrote about it’s place in Copenhagen:

The Copenhagen Fools

It was freezing cold in Copenhagen and the way into the Bella Center was lined with delegates and journalists eager to participate in what was called the most important conference since the Second World War. Little did they know that they would have to stand in the freezing winter day for eight hours, only to be turned away without an explanation.

At the Metro station stood two Taiwanese women in chicken and a cow costumes. They distributed flyers with their vegetarian agenda. What fools, I thought, there should be solar energy advocates in their place.

Copenhagen saw a huge, mostly peaceful demonstration. “Bla Bla Bla…Act Now!” and “There is no Planet B” were the helpless paroles of the 100,000 young people, whose future was ground up to sawdust in the political machinery. In many other cities around the globe, protesters marched as well.

All this made some impression on the delegates who were working on a deal, but it was not enough to get over the stage of bickering. The poor countries used the stage to demand money from the rich. The industrialized countries made their reductions dependent on other countries actions. The soon-to-be-flooded islands ignored that they were ultimately dependent (like Maui) on climate-destroying flights. And all were waiting for The One.

He arrived on the 18th and he was pissed. In his first speech he said that he was here to act and not talk. Anger and irritation were in his voice. He teamed with Chinese Premier Wen Jiabao to draft a late night compromise. But in the end, even Obama could not get more than a faint declaration that was even weaker than the positions before the conference. Say goodbye to your beach mansions, Wailea.

Back to the chicken and the cow.

According to a Sept 2009 Worldwatch Institute report, more than 51% of worldwide emissions are due to raising livestock, not 18% as was previously assumed by the FAO. Expect emissions to double by 2050.

This is a revolutionary insight. According to the numbers, a 1% reduction in worldwide meat intake has the same benefit as $3 trillion in solar energy investments. Hundred times today’s solar market. It is time to rethink how we can save the world.

The fools, it turned out, were right.

Chris Mentzel bms@mentzel.com
15.
David Michael says:
January 12, 2010 at 1:32 am

It’s an interesting story from Goodland and Anhang. But there is an unfortunate bias against livestock in the strenuous effort to measure all the omissions and errors that weigh against the sector, but then neglect factors that can be positive, including, for example, changes in soil carbon. Deep rooted perennial pastures can sequester more soil carbon than forests in well managed soils. Measurement of soil carbon is or would be a challenging exercise if credits are to be given for increased soil carbon content. But that’s OK because such measurement problems have not stopped the authors from making claims about the carbon absorption foregone in land set aside for livestock and feed production.

It’s also a little disingenuous to dismiss Sue Michalsky’s comments about natural grasslands on the grounds the article was already over the worldwatch word limit, especially when it leads off with a sensational claim that emissions from agriculture are understated by a factor of 3.

But lets assume the theme is valid and that agriculture actually accounts for over 50% of emissions. This seems also to have implications for the distribution of emissions between developed and developing countries. For example, according to FAO statistics less developed countries account for around 20% of the global cattle stock and developing countries overall account for over 70%. Similar ratios probably exist for other ruminants. Does this mean the conventional wisdom that global warming is due mainly to high income country consumption is now false and that developing countries are actually the gig emitters?

One thing, however, we can all agree on is that population growth is the key risk for measures to effectively combat climate change.

Despite the above comments I liked the article. It points out anomalies in the measurement of emissions. I would like to see a comment from Robert or Jeff on the soil carbon issue. I think the subject came up at Copenhagen.

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