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The Sheep Albedo Feedback

Filed under: — raypierre @ 1 April 2007 - (Español)

The already-reeling "consensus" supposedly linking climate change to CO2 is about to receive its final coup-de-grace from a remarkable new result announced in a press conference today by Dr. Ewe Noh-Watt of the New Zealand Institute of Veterinary Climatology [1]. Noh-Watt and his co-workers, describing work funded by a generous grant from the Veterinary Climate Science Coalition, declared "We have seen the future of climate — and it is Sheep." Prof. Jean-Belliere Poisson d’Avril, star student of Claude Allegro Molto-Troppo (discoverer of the Tropposphere) reacted with the words, "Parbleu! C’est la meilleure chose depuis les baguettes tranchées!"

The hypothesis begins with the simple observation that most sheep are white, and therefore have a higher albedo than the land on which they typically graze (see figure below). This effect is confirmed by the recent Sheep Radiation Budget Experiment. The next step in the chain of logic is to note that the sheep population of New Zealand has plummeted in recent years. The resulting decrease in albedo leads to an increase in absorbed Solar radiation, thus warming the planet. The Sheep Albedo hypothesis draws some inspiration from the earlier work of Squeak and Diddlesworth [2] on the effect of the ptarmigan population on the energy balance of the Laurentide ice sheet. Noh-Watt hastens to emphasize that the two hypotheses are quite distinct, since the species of ptarmigan involved in the Squeak-Diddlesworth effect is now extinct.

The proof of the pudding is in the data, shown in the Figure below. Here, the Sheep Albedo Index is defined as the New Zealand Sheep population in each year, subtracted from the 2007 population. The index is defined that way because fewer sheep means lower albedo, and thus a positive radiative forcing. It can be seen that the recent warming can be explained entirely by the decline in the New Zealand sheep population, without any need to bring in any mysterious so-called "radiative forcing" from carbon dioxide, which doesn’t affect the sunlight (hardly) anyway — unlike Sheep Albedo. Some researchers have expressed surprise at the large effect from the relatively small radiative forcing attributable to New Zealand Sheep, or indeed to New Zealand as a whole. "This only shows the fallacy of the concept of Radiative Forcing, which is after all only a theory, not a fact," says Noh-Watt. "Evidently there are amplifying feedbacks at work which give the Sheep Albedo Index a disproportionate influence over climate."

"A real breakthrough was using the statistical technique pioneered by Frusen-Glädje and Haagendassen in their study of the solar-climate connection." said Noh-Watt "Just as in their case, to get a good match to the observed climate, we had to optimize our smoothing algorithm by smoothing some parts of the sheep record more than others, and then rescaling the results." The optimized smoothing was applied to the years 1975-1991. Noted skeptic Rasmus Benestad has criticized this technique as meaningless curve-bashing (see footnote [3] below), but according to Noh-Watt, " All these guys are interested in is getting rich by riding their bicycles to work and selling carbon credits to the EU."

Not everybody agrees with the Sheep Albedo Hypothesis. Leading the flock of skeptics is the New Zealand Sheep Farmers Guild. Their spokesman, Steve Ramsturf (no relation) was quoted as saying "Baaah, Humbug. No matter what goes wrong with the world, they’re always trying to blame the poor New Zealand Sheep Farmer. First it was the methane belch tax. Now this Albedo thing. "

The recognition of the role of sheep albedo opens up some fascinating new possibilities for climate change mechanisms. There is in fact an important destabilizing feedback in the system: as climate gets warmer, there is less demand for wool sweaters and wooly underwear. Hence the sheep population tends to drop, leading to even more warming. In an extreme form, this can lead to a "runaway sheep-albedo feedback," which is believed to have led to the present torrid climate of Venus. Most researchers do not think this could happen on Earth, though. In fact, Oprah and Averell Chanteur, authors of the popular "Unstoppable" series (soon to be a major motion picture) say that the warming will usher in a new era of peace and prosperity, with less enslavement of domestic wool-bearing animals. The hypothesis is laid out in their forthcoming book, "Unstoppable Sheep, every five or six days," which expands on earlier popular titles in the series, such as "Unstoppable daylight, every 42 hours," "Unstoppable Summer, every 17 months, " and the ever-popular autobiographical work "Unstoppable nonsense, every two or three years."

However, Dirk Blitzen, noted researcher from Hogwartz Institute of Technology, has proposed an additional wrinkle on the sheep-albedo idea, which he calls the "sheep-Iris effect" (see Dasher et al. [4] for details). According to Blitzen, a reanalysis of Landsat images shows that as the climate gets warmer, sheep tend to huddle together less. Since wool has a lower emissivity than bare ground, the lack of huddling allows more infrared emission to escape from the ground, cooling the planet and stabilizing its climate. "Frankly, I don’t see how the climate can change much at all," stated Blitzen in recent testimony before the House of Lords, "To be honest, at this point I have a little trouble figuring out how there can even be summer and winter. In the end, I think it will turn out to be a problem with the data." Ozark Junior College satellite expert Jhon Chrystal agrees; his new analysis of MSU satellite data in fact casts doubt on the "consensus" that summer and winter have different temperatures.

But the sheep story may not be as simple as it seems. Hendreck Svampmark of the Danish Institute for Solar-Sheep Interactions notes that at the same time the number of sheep has been going down, the number of cows (which have a lower albedo than sheep) has been going up. "We believe that what is really behind it all are Galactic Cowsmic Rays, which are transmuting sheep DNA into cow DNA." Svampmark hypothesizes a currently undetected particle flux, which he calls "Cowsmic," because there is no observed trend in any of the better-known components of the Galactic Cosmic Ray flux. "We are trying to get money to put sheep in dark-matter accelerators to test our hypothesis, but there’s a hold-up with PETA. It’s all a big conspiracy to protect the consensus, I say."

Footnotes:

[1] Noh-Watt, Ewe "Sheep-Albedo Feedback: A paradigm shift for climate change science." To be submitted to Readers’ Digest, "Humor in Uniform" section.

[2] Squeak, P.P. & Diddlesworth, I.R. 1987. The influence of ptarmigan population dynamics on the thermal regime of the Laurentide Ice Sheet : the surface boundary condition. In eds Edwin D. Waddington & Joseph S. Walder, The Physical Basis of Ice Sheet Modelling (Proceedings of a symposium held during the XIX Assembly of the International Union of Geodesy and Geophysics at Vancouver, August 1987), p.381-384.

[3] Benestad, a well-known spoilsport, points out that without the "optimized" smoothing out of the sheep-albedo-dip in the 1970′s, the correlation breaks down; it breaks down further if one looks at the pre-1966 record. His unprocessed version of the data is shown below:

[4] Dasher ON., Dantzer ON, Prantzer ON, Vixen ON, Comet ON, Cupid ON Donner . , and Blitzen, D.R , (2007) "Why does Rudolf’s nose glow so bright? Infrared effects of mammalian herd behavior." Bull. Tromsø Inst. Reindeer Husbandry


206 Responses to “The Sheep Albedo Feedback”

  1. 151
    Ray Ladbury says:

    Re 143: John, I fear you may be screwed and tatooed. Your brother is suffering from an incurable disease: Male Answer Syndrome or MAS. It is more common than one would think–as all of our wives know. Your brother seems to believe that since he has once solved tha Navier-Stokes Equation, then he must understand any nonlinear system he comes across. I fear that to admit that there are things he does not understand might be too great a blow for his ego to bear. Just keep him from voting.
    Actually, it is clear that his opposition stems from politics rather than an understanding of the science. The Economist Magazine has had some rather good pieces on climate change, and it can hardly be dismissed as a liberal mouthpiece. Unfortunately, your brother will probably dismiss it as “Eurotrash”. You might point out to him all of the politicians, businessmen and others with impeccable conservative credentials who have acknowledged that anthropogenic climate change is a threat–e.g. James Baker, most Republican Senators, many Fortune 500 CEOs and so on. It is clear that he will trust no source unless it is of a conservative bent. In fact, he may have gone so far to the right that his politics are coming back on the left again–he sounds more radical than conservative.

  2. 152
    John Mruzik says:

    I am 56 year old, work 18 hours 6 days a week as a emergency physician, I am on call 24 hours a day. I guess I can quit and try to convert a GW denier who has two masters and a phD in materials science. I just wanted help. Sorry to leave a long post, perhaps you could direct me to a more helpful site. I remember now why I left the accedemic world.

  3. 153
    John Mruzik says:

    Thank for the help and non-arogant response. Please direct me to a web-site that might help me repute GW deniers without quiting work and spending all day in research.

  4. 154
    Lynn Vincentnathan says:

    RE #149, one solution: Stay at home and eat vegetarian. Or cycle rather than drive to the burger place, then order a veggie burger.

  5. 155
    Ike Solem says:

    Now I understand that Monty Python claim in The Holy Grail of how sheep’s bladders may be used to prevent earthquakes!

    Reducing the global sheep population means that less light will be reflected to space; this will cause the ice sheets to melt, leading to ewe-static rebound and a higher incidence of earthquakes.

    Looks like Monty Python got it wrong; harvesting sheep bladders will actually lead to more earthquakes, not less. On the other hand, sheep flocks may expand due to the economic demand for sheep bladders for earthquake prevention… Perhaps we could launch the sheep into orbit; where they could more effectively block sunlight?

  6. 156
    J.C.H says:

    John – I would start him with Joseph Fourier and Svante Arrhenius.

    Einstein said it would just take one scientist to prove him wrong, so ask him to find just one scientist who has proved those two dinosaurs were wrong in any material aspect of their theories.

  7. 157
    SomeBeans says:

    John – I’d go have a look at Gristmill’s skeptics guide (http://gristmill.grist.org/skeptics). Its more focussed on the problem you have than here…

  8. 158

    John,

    Considerable research was done in the 1930s into the art of persuasion and it was found that, for men at least, it is impossible to win an argument. Even if you persuade him with the science to agree with you, he will still harbour the thought that there may be an unknown factor which you have not considered. Moreover, if you prove him wrong he will lose face, and no man can accept that. The research was carried out by Dale Carnegie, and is recorded in his book “How to Win Friends and Influence People.”

    The correct approach is to agree with him. Point out that he is correct. It is a well known fact that all the radiation in the greenhouse bands is absorbed by the atmosphere within the first 30m (100ft) from the surface. Thus doubling the concentration of CO2 will not affect how much radiation is absorbed, only where it is absorbed. It will then be absorbed within first 15m (see Beer’s Law,) and so it will double the warming near the surface where we live.

    Then you can point out to him that it is not the lunatic left that are publishing the IPCC FAR report. It is thousands of scientists just like him. Does he really think that they are going to admit that they are all wrong, and that their model, which predicts warming rising only with the log of the concentration, is faulty?

    Scientists are like sheep. Just as it is difficult to get a flock of sheep to go through a gate, so it is difficult to get scientists to accept a new theory. But once one has, then they all follow. However, if the theory is wrong, then it is well nigh impossible to get them back through the gate and through another. If they find it hard to accept a new theory, how much harder do they find it to reject an old one first?

  9. 159
  10. 160
    Ray Ladbury says:

    John Mruzik, Everybody makes mistakes–and in some ways it is probably useful for folks here to see the absolute certainty some of their opponents have. Believe me, I understand your frustration. I have been tilting at windmills of those with similar denial complexes, and it is definitely complicated by the fact that the denialists take any attack on their position personally. My favorite is when they resort accuse us of ad hominem attacks–usually after implying that all climate scientists are money-grubbing frauds.
    All I can say is that if you find a strategy that works on your brother, come back and tell us about it–PLEASE!

  11. 161

    Hi John,

    Here is proof that it is the scientists that are pushing climate change not the press and the tree-huggers. See http://www.royalsoc.ac.uk/page.asp?id=6229

    One of the founders of the The Royal Society was Issac Newton, and George Stokes of the Navier-Stokes equation was also a fellow.

    Cheers, Alastair.

  12. 162

    Re:161
    I agree with Alastair that Martin Rees is articulating a much cleaner case than Lord May or departed RS Senior Manager for Policy Communications Robert Ward .

    So he should, but the charge of having a policy agenda to push around the wool sack floor still stands:

    http://adamant.typepad.com/seitz/2007/03/letter_from_a_n.html

  13. 163
    Lynn Vincentnathan says:

    RE #153, John, why not have your brother come to this site and air his doubts or beliefs. That way the scientists can respond to each one.

    I remember from 9th grade science class — the boy scout list:
    A scientist is open-minded.
    A scientist is honest.
    A scientist is objective.
    LABORATORY: follow the first 5 letters, not the last 7.
    And I learned later: A scientist is humble (or if not will soon be made to eat humble pie, or pride comes before the fall).

    If he remembers and values these, he might be swayed.

    Also, it’s important to point out that while scientists may get big grants to study things, the money mainly goes for the project and to pay their regular (not enhanced) salaries that they would have gotten even without the grant. (I also know that universities often suck up at least 1/2 of it supposedly into their general budget…and no one sees it again, poof).

    OTOH contrarian scientists are paid huge consultant fees for their denying GW, above and beyond their salaries. And there’s a lot of money from where that comes from. I’m just happy that most scientists are scupulous & have not gone over to the dark side.

  14. 164
    Chuck Booth says:

    John Mruzik,
    If your brother is a scientist, he should be able to read and understand the ICPP reports – ask him to read those and explain to you which conclusions, and which peer-reviewed papers cited as evidence, he doesn’t believe. Surely, he would not appreciate a biologist, or geologist, or a climatologist, telling him that what he knows to be true in the field of materials science is flat out wrong? Likewise,he should understand that climatologists tend to get annoyed when educated people from other disciplines tell them their climate models wrong, esp. when those educated people offer explanations based on misinformation or misconceptions about atmospheric physics and climate science.

  15. 165
    Chuck Booth says:

    Re 164 Oops..that would be IPCC reports.

    Sorry.

  16. 166
    Darren McManaway says:

    Been both a Kiwi and a climatologist – this really is the funnest thing I have read in years.

    Well done guys!!

  17. 167
    Joseph O'Sullivan says:

    I will admit I total fell for the April fools joke.

    At first I skimmed the post and I thought it was about the land use part of climate change, and the first thing that struck me was the discussion of ptarmigan. I thought “hey there are not ptarmigan in New Zealand”, and I carefully re-read the post and had a good laugh.

    Well done! Even though there is an impending crisis, that does not mean we can not have a good sense of humor.

  18. 168
    Geoff Russell says:

    WARNING: This is a serious comment.

    FAO figures show that the world produces about 570 calories per person per day
    per annum of rice — for about 60 Tg/yr of methane (e.g. Houghton “Global
    Warming — The Complete Briefing). Beef and sheep between them produce about
    50 calories per person per day — for about 90 Tg/yr of methane (again using
    Houghton’s figure).

    If the Chinese ever seriously switch from rice to beef then all the carbon
    sequestration in the world won’t save us from the methane forcings. Are
    the Chinese moving to beef? Well yes, they are, again FAO figures show Chinese
    beef and sheep consumption has gone from 11.4 cal/person/day in 1990
    to 46 cal/person/day in 2005.

    But instead of policy makers taking meat seriously as a climate issue. All
    we get, at best, are farting cow jokes. So while climate scientists, and
    others, stand around BBQs talking earnestly about arctic melt and brown
    coal, a really serious and quickly fixed (i.e., requiring no new technology)
    forcing is literally under their noses. Meat reduction is a serious issue that
    is, almost, uniformly ignored by “objective” scientists. Why? And if it
    isn’t ignored, then can you please provide references of scientists who
    have given it a mention in serious papers.

    P.S. I’ve only recently discovered RealClimate, it is an absolutely
    brilliant site.

    Cheers,
    Geoff Russell

  19. 169
    Chuck Booth says:

    Re #168 I’m not so sure this problem has been totally ignored. For example:

    A country-specific, high-resolution emission inventory for methane from livestock in Asia in 2000

    Kazuyo Yamaji, Toshimasa Ohara, Hajime Akimoto

    Atmospheric Environment,37(31), 4393-4406, 2003.

    Methane emissions from livestock in South, Southeast, and East Asia were estimated to be about 29.9 Tg CH4 in 2000 using the Food and Agriculture Organization database and district-level data on regional activity and emission factors, considering regional specificities. These emissions consisted of 25.9 Tg CH4 from enteric fermentation and 4.0 Tg CH4 from livestock manure management systems. India had the greatest production, with 11.8 Tg CH4 from livestock, primarily cattle and buffaloes. China was also a high-emission country, producing about 10.4 Tg CH4. To determine their spatial distribution, emissions at the country and district levels were plotted on a 0.5Â?~0.5Â?â?¹ grid according to weight, using high-resolution land cover/use datasets. This gridded database shows considerable emissions throughout the Ganges basin, with peak emissions exceeding 30 Gg CH4 grid-1 in the Ganges River delta. The total methane emissions from livestock increased by an average of 2% per annum from 1965 to 2000. The recent increase in methane emissions in China was especially remarkable.
    http://www.jamstec.go.jp/frcgc/research/d4/pubs/03ky1ab.htm

    Moreover, the relative importance of cattle vs. rice paddies with regard to methane emission is well established, and methods to reduce methane production by cattle have been under development during the past twenty years:
    http://www.epa.gov/rlep/faq.html
    http://www.ciesin.columbia.edu/docs/004-180/004-180.html
    http://jeq.scijournals.org/cgi/content/abstract/32/1/269
    http://www.umanitoba.ca/afs/fiw/040304.html

    Finally, for what it’s worth: As most of their methane is produced in their forestomach (rumen and reticulum), I suspect cows emit more methane when they belch than when they fart.

  20. 170
    Chuck Booth says:

    RE #168 Rice vs. Cattle in China

    It’s perhaps also worth noting that the FOA report to which you referred made the news in China:

    UN Report: Rearing cattle produces more greenhouse gases than cars

    Peopleâ??s Daily Online December 01, 2006

    Cattle-rearing generates more global warming greenhouse gases, as measured in CO2 equivalent, than transportation, according to a new United Nations report released on Thursday.
    “Livestock are one of the most significant contributors to today’s most serious environmental problems,” senior UN Food and Agriculture Organization (FAO) official Henning Steinfeld was quoted by the Ghana News Agency as saying on Thursday.
    “Urgent action is required to remedy the situation,” he said in a statement released by the UN Information Centre in Accra…

    http://english.people.com.cn/200612/01/eng20061201_327245.html

    If you are really asking, “Do the latest climate models take into consideration predicted shifts in agriculture around the world?” I don’t know, but I can’t imagine they would ignore this. Have to check the IPCC reports…

  21. 171
    Dave Rado says:

    Re. 168 and 169 – isn’t methane from cattle digestion part of the carbon cycle and therefore not a *net* affector of long term atmospheric carbon levels?

  22. 172
    Chuck Booth says:

    Re 171 Bovine methane and the carbon cycle

    Well, yes, any carbon transformed within the biosphere is part of the carbon cycle. But, plants take in CO2 from the atmosphere (the level of which is rising due to combustion of stable hydrocarbons extracted from reservoirs in the earth’s crust), cows eat the plants, and the microbes in the cows’ stomachs produce methane, a more potent greenhouse gas (i.e., better absorber of terrestrial IR) than the CO2 that was in the atmosphere. I don’t have figures handy, but I think it is safe to say there is a lot more bovine biomass producing methane now than there was a few centuries ago. And this could increase further as countries like China become more developed (the original point here). This is explained in the FAO report, and in the People’s Daily news article I cited in #170.

  23. 173
    Ray Ladbury says:

    Chuck, the question is how long the methane stays in the atmosphere. I believe it gets oxidized to CO2 and H2O on a timescale of years, does it not. In which case, you at least do not have the buildup like we see with CO2. And since the carbon ultimately came from plant material–and demonstrably is not fossil carbon, does it have a significant contribution?

  24. 174
    Geoff Russell says:

    Re: #169. My mistake, it isn’t that there are no scientists measuring
    livestock methane or working on reducing emissions from ruminants, but
    there is, it seems a serious asymmetry in the way livestock emissions
    are approached as opposed to motor vehicle or other emissions. Every
    Government has websites telling people things they can do to reduce
    greenhouse emissions: drive less, buy a Prius, turn off lights, change
    thermostats, etc etc. I haven’t found one which advises people to eat
    less meat.

    I emailed James Hansen a while back, to ask him why this advice
    was missing from one of his papers advocating methane reduction.
    He replied: “Geoff, a very good point, which I usually forget to mention —
    thanks for reminding me.”.

    It seems everybody forgets, that’s my point.

  25. 175
    J.C.H says:

    I would think that the American Bison probably produce similar emissions. Their population before Columbus can only be estimated, but I would not be surprised if there were more of them then than there are cattle today. Other than man, they have few predators.

  26. 176
    Hank Roberts says:

    Looking this up: +methane +feedlot +grass

    Among the first page of hits with Google, this: http://www.foodrevolution.org/grassfedbeef.htm

    “According to David Pimentel, a Cornell ecologist who specializes in agriculture and energy, the corn we feed our feedlot cattle accounts for a staggering amount of fossil fuel energy. Growing the corn used to feed livestock in this country takes vast quantities of chemical fertilizer, which in turn takes vast quantities of oil. Because of this dependence on petroleum, Pimentel says, a typical steer will in effect consume 284 gallons of oil in his lifetime. Comments Michael Pollan,

    “We have succeeded in industrializing the beef calf, transforming what was once a solar-powered ruminant into the very last thing we need: another fossil-fuel machine.”

    “In addition to consuming less energy, grass-fed beef has another environmental advantage – it is far less polluting. The animals’ wastes drop onto the land, becoming nutrients for the next cycle of crops. In feedlots and other forms of factory farming, however, the animals’ wastes build up in enormous quantities, becoming a staggering source of water and air pollution. ….”

  27. 177

    re 168

    “All politics is local”
    In the land of the bean and the Cod
    But Beefeaters here are quite vocal
    “If beans mean methane
    We’re all scrod.”

  28. 178
    Geoff Russell says:

    Re: #171 and #172. Imagine a planet with plants and an atmosphere and some
    level of methane such that sources and sinks are balanced. Now breed
    up a billion ruminants which are regularly eaten and replaced. Atmospheric
    methane will rise — presumably only until it reaches some new equilibrium.
    But if you keep adding more ruminants, then it will keep rising (pending
    some change in the sinks — more hydroxyl from somewhere).
    The total carbon in the system doesn’t change, but the radiative forcing does.
    Effectively, ruminants and most other animals convert low forcing carbon
    to high forcing carbon.

  29. 179

    Re 174 – Geoff,

    Jim Hansen has been advocating reducing methane rather than CO2 to combat global warming for several years now. His most recent comments can be seen and heard here.

    Since the main anthropogenic sources of methane are the paddy fields in southern Asia, it does not seem a good idea to me that half the world’s population should give up their staple food and starve, in order that US citizens can continue their way of life, which appears to consist of driving SUVs, and eating beefburgers from McDonalds. It seems that you and Jim Hansen think otherwise!

  30. 180
    Geoff Russell says:

    Re: #179 – Alastair, please see my original message #168. For
    anthropogenic methane emissions see:

    http://www.mnp.nl/edgar/model/v32ft2000edgar/docv32ft2000/

    The beef burgers provide very few calories per kg of methane
    compared to rice.

  31. 181

    Re #180 Geoff,

    I still think there is more chance of you saving the world if you give up driving your car to the supermarket, than if you stop eating hamburgers.

  32. 182
    J.C.H says:

    The world has always been teaming with plenty of ruminants.

    Right now, because of ethanol, the competition for corn is poppin’. Americans are about to pay a whole bunch more for any meat from a beast that consumed corn to gain weight. Do farm-raised catfish eat corn? Yes, they eat some corn. Chickens eat corn, so your eggs come from the same amount, by ratio, of fossil fuel. Corn brings animals to market faster, which makes the product cheaper.

    Bottom line, the fossil fuel used to produce corn (a major portion of the fossil fuel used to produce beef) is not going to be much nullified by not eating beef; at least, not until cellulosic ethanol/some other renewable becomes a reality in the market place.

    Also, if nobody in America eats beef, grass fed or corn fed, you would soon have around 100 million rotting critters. Nobody is going to feed 100 million pets. What would that do to emissions?

    Like veggies don’t require fossil fuels to produce? Find a target that has a higher net yield.

  33. 183
    Chuck Booth says:

    Re 173
    Ray,
    According to the U.S. E.P.A. (http://www.epa.gov/methane/scientific.html), the half-life for methane in the atmosphere is 12 years, and levels have risen from 70 ppb in the year 1750 (based on ice core samples) to 1,745 ppb in 1998; levels were relatively stable at 1751 ppb from 1999 to 2002 (most recent data shown). The EPA methane webpage also indicates that methane reacts with hydroxyl radicals to form CH3 (not quite sure what this combines with) and water; it doesn’t mention this forming CO2. Without having read the literature on this topic, I have to wonder if increased cattle production hasn’t contributed to the rise in atmospheric methane levels over the past 250 years. The FAO report Geoff Russell referred to (and about which I quoted some comments from a news article) seems to consider cattle a problem, not only because of the methane, but also their emissions form HNO3 vapor, another greenhouse gas and contributor to acid rain.

    There are, of course, many good reasons to cut back meat consumption:

    In addition to the fossil fuels combusted in raising cattle (noted by Hank Roberts, I think), David Pimental at Cornell also estimated a decade ago that the grain fed to the 7 billion head of cattle in the U.S. (not 100 million, JCH!) could feed 800 million people. And , the replacement of rain forest with cattle ranches in the Amazon basin should be a major cause of concern.

    JHC: As for American bison, according to Charles C. Mann (1491: New Revelations of the Americas Before Columbus), the large bison herds seen by settlers in the west in the 19th century were probably an artifact of the decimation of Native American hunters over the preceeding 250 years. Prior to the arrival of Europeans on North America, hunting probably kept the herds at much smaller levels. Also, because of allometric scaling effects, a given biomass of large bison will consume less food and, almost certainly, produce less methane, than an equal mass of smaller domestic cattle. I don’t know anything about large populatations of ruminants elsewhere (e.g, Caribou in the Arctic, or grazers in Mongolia), but I suspect there are far more ruminants on the planet now than ever before; that is just a guess, though.

  34. 184
    J.C.H says:

    Chuck – there approximately 100,000,000 (one hundred million) cattle in the United States. By the time I was eighteen I think I had vaccinated, castrated, dehorned, blood tested, ear tagged, and branded about half of them. I love the smell of burning flesh in the morning and the sound of bellerin’ at the saw.

    The guy says 7 billion livestock animals in the United States. I know some ranchers who would like to hire him to make head counts at the sale barn.

    I believe that India has the world’s largest population of cattle. I wonder why? A suggestion: kill theirs.

  35. 185
    Chuck Booth says:

    Re 184 OK, JHC, Iâ??ll concede to your intimate knowledge of cattle: The EPA estimates that the U.S. has 100 million head of cattle, with about 1.2 billion large ruminants world wide (at least one published report cites a total number for ruminants world wide, both domestic and wild, at over 4 billion*). I donâ??t know where David Pimentel got his figure of 7 billion animals in the U.S., though I may have misread that; Iâ??m trying to track down the article from the Cornell Univ. Veterinary College that I read on Pimentelâ??s work.
    The EPA also estimates that â??Globally, ruminant livestock produce about 80 million metric tons of methane annually, accounting for about 28% of global methane emissions from human-related activitiesâ?¦.In the U.S., cattle emit about 5.5 million metric tons of methane per year into the atmosphere, accounting for 20% of U.S. methane emissions.”
    http://www.epa.gov/rlep/faq.html

    *Leng, R. A. 1993. Quantitative ruminant nutrition – A green science. Australian Journal of Agricultural Research 44: 363-80.
    http://www.ciesin.columbia.edu/docs/004-180/004-180.html

    Iâ??ll have to ruminate on these numbers for a while.

  36. 186
    J.C.H says:

    I emailed a researcher and suggested to him that India be pressed to eliminate the majority of its cattle. I think they would be entitled to significant credits if they were to do that. They have a huge number of cattle – perhaps as many as 300 to 400 million.

    I also suggested he test the methane emissions from deer. While hard to estimate, the population of deer in the United States may exceed 50 million. They’re a pest. They love to get into cornfields and eat all your popcorn. If they are producing significant methane, there is no reason to have more than a few million deer in this country.

    One thing that surprised me was the difference between grass-fed beef and corn-fed beef with respect to methane emissions. Just based upon the STUFF they produce on corn, I would have guessed a corn-fed animal would produce more methane. That does not appear to be the case. A California researcher has found dairy cows are producing about half the methane prior research, which they say was done in 1938, indicated. Dairy animals are generally full-sized, and exceptionally well fed with grains. Cow-calf operations have a large grazing component, and their animals are probably producing more methane per animal.

    I rarely eat beef. We used to have a small herd of buffalo, which we finished on corn. It’s the very best meat – very lean and manly tasting stuff.

    I do think wild ruminates outnumbered our domesticated populations in pre-European America. That’s my hunch. One thing I do know, they weren’t eating corn back then. The Indians who lived on our ranch land before the Sioux massacred them were farmers. They probably ate buffalo, but I doubt they depended upon them like the Sioux did.

  37. 187
    Nick Gotts says:

    Re #186 It’s true grass-fed cattle produce more methane than corn-fed, but against that you have to consider at least three factors: the CO2 and N20 emitted in producing the corn, the ability of untilled grassland to act as a carbon sink, and the excess methane produced from manure “lagoons” as opposed to allowing the same amount of manure to degrade in aerobic conditions in a field. I don’t know what the overall balance is. Many of India’s cattle are draught animals – I don’t know how valid the stereotype of millions of “sacred cows” doing nothing useful is. Fairly simple supplementation could greatly increase the efficiency of cattle in many poor countries, in terms of units of milk/meat/labour per litre of methane. Wild ruminants in North America may have outnumbered current domesticates, though I doubt it, but they wouldn’t have been eating anything like as much – both beef and dairy cattle are fed huge amounts to produce the stuff people consume. By the same token, I’d think the amounts of methane deer produce are trivial. I found some figures from 1993 in a quick internet search, suggesting wild ruminants in total produce less than 1/10 of the methane domestic ones do.

  38. 188

    [[I emailed a researcher and suggested to him that India be pressed to eliminate the majority of its cattle.]]

    Cows are sacred in India, and killing them is sacrilege. We tend to be amused or contemptuous of this theme, but it has a very logical underpinning to it — cows pull the plows. Wipe out the cows and you wipe out Indian agriculture.

    A request to India to kill most of its cattle would be seen as offensive and would, at best, be ignored.

  39. 189
    James says:

    Re #188: [A request to India to kill most of its cattle would be seen as offensive and would, at best, be ignored.]

    But isn’t this exactly like the response you get from the average American (or Western European, etc), if you suggest they give up eating meat?

  40. 190
    Alvia Gaskill says:

    Just when my Global Albedo Sheep Project was about to get off the ground, our research facility is shut down for no reason. It must have been all the bad publicity here at realclimate. Thanks alot guys.

    http://english.pravda.ru/news/world/29-03-2007/88777-sheep-0

    http://www.newsobserver.com/559/story/559249.html

    http://www.newsobserver.com/100/story/557976.html

  41. 191
    Nick Gotts says:

    Re #189 “Re #188: [A request to India to kill most of its cattle would be seen as offensive and would, at best, be ignored.]

    But isn’t this exactly like the response you get from the average American (or Western European, etc), if you suggest they give up eating meat?”

    No, in the sense that objecting to the loss of your livelihood is more reasonable than objecting to the loss of a luxury (in a situation where both have bad effects on others). The average American/W. European could give up eating meat without endangering their health – indeed, probably benefiting it; many Indian farmers would be destitute without their cattle, which supply milk in otherwise protein-poor diets, manure and urine to fertilise the land, and draught power. It is the poorer farmers who are cattle-dependent – rich ones can afford tractors and artificial fertilisers. Whether this mechanisation is a net plus or minus from the point of view of GHG emissions I don’t know – but measures to improve cattle productivity by supplementation (and so reduce the numbers needed) might be the best approach.

  42. 192
    James says:

    Re #191: [...many Indian farmers would be destitute without their cattle...]

    I think we’re arguing at cross-purposes here. I understood the suggestion to be that India kill off their excess sacred cows – the unowned multitudes that for religious & cultural reasons are allowed to roam at will – not working draft & dairy cattle.

    I think that would be the sense of Indian response to such a suggestion. The objection would be rooted in religion & culture, not in the practicalities of agriculture, and so would be no different to the average Westerner’s response to the idea that they should give up meat.

  43. 193
    Numb Nuts says:

    Yikes! Methane and CO2, silent killers! Does this mean I have to stop brewing my beer and farting?

  44. 194
    Hank Roberts says:

    America worships the automobile. Go figure.

  45. 195

    [[Yikes! Methane and CO2, silent killers! Does this mean I have to stop brewing my beer and farting?]]

    I’m afraid so. But whatever you do, don’t stop adding your valuable commentary to this and other web sites.

  46. 196
    J.C.H says:

    So the American ox is “goreable”, but the Indian ox is “ungoreable”? They are producing about 4 times as much methane, and they have significantly more cattle than other countries that both rely on draught animals and eat meat.

    Num Nuts – you don’t have a cud, so I would say you only have to give up farting if you redrink your own beer barf.

    A reasonable population for Indian cattle would be around 40 million. If you are serious about reducing methane, the rest should be boinked in the head.

    Horses do not emit methane, or at least not much. We have a sort of religious opposition to eating horsies. For instance, as I understand it, explained to me by a European who owns a horse kill plant in Texas – in Texas you can butcher horses and you can eat horse meat, but not horse meat that was butchered in Texas. Horse meat butchered in Texas has to be shipped out of Texas to be legally eaten by a human being. He was shipping most of his meat to Europe. To eat legal horse meat in Texas, a Texan has to buy meat that was butchered somewhere else and then shipped into Texas. To me, that byzantine mess sounds sort of religious: kind of biblical like.

    So I think we could compromise. If the Indians were to reduce to 40 million cattle, we would agree to replace cow-calf operations with mare-colt operations. Their religion would take a hit and our religion would take a hit. It would be pain for all. Just imagine all the screaming little kids be drug to eat pony burgers.

    Between the two, you would be knocking off around 400 million large methane producers, which is a significant percentage of the total number of ruminants on the face of the earth.

    And guess what, most people would not know the difference. Think you haven’t chewed up some Kangaroo; think again. It’s amazing how a few Kangaroos make hamburger inventories last and last.

  47. 197
    Numb Nuts says:

    Thanks for the kudos Dr. Levenson. And J.C.H., I’ll try that redrinking the beer barf routine tonight (it may be an acquired taste), but I’m not going to give up farting. I’ll pay Al Gore the Dangerous Emissions Tax before I’ll give up farting. I wonder how much that costs? What does he do with all that money?

  48. 198
    Jim Roland says:

    Further to #8, a petition has now been started on the Prime Ministerial website against the proposal: http://petitions.pm.gov.uk/barbecue/

  49. 199
    Aaron Frost says:

    I am new to this site and having read a bit through this I am still confused as to whether or not this is actually a serious article!

    Honestly, it may not have been necessary for this hypothesis to actually be tested since most people that have at least taken a general Earth Science course could tell you that anything light in color has a high albedo. Even if one does not know what albedo is, most know not to wear black during the long, hot summer days as to not make them hotter! So, the findings here are certainly to no surprise that masses of white sheep are going to lower temperatures a bit. So is that to say we should all adopt sheep to fight global climate change? Or perhaps we should paint all of our buildings and streets white to raise albedo too?

    It is easy to take a sarcastic view to this (a joke or not?), but global climate change is a serious matter and as you all know, the more information we can gather to understand it, even quantifying sheep albedo, the better we can fight it. So understanding the feedbacks and possibly offsets to real temperatures is important stuff! I am certainly not advocating for the sheep, since, regardless of how much we can lower temperatures by adopting them or painting the town white, we would only be disguising the raising temperatures and its associated problems by sweeping it under the rug for a period, until the pile is found by the next generation, bigger and worse than ever.

    I hope I didn’t spoil the fun :) – party on, we have to have some fun while saving the world, right?

  50. 200
    Nick Gotts says:

    Re #192 I don’t have any information on how many unowned “sacred cows” there are in India. You talk about “unowned multitudes”, but my guess would be very few if any have no owner – a cow (or for that matter a bull or bullock) is a valuable asset, and can be used as collateral for loans in addition to the other uses already noted. However
    http://tedeboy.tripod.com/drmichaelwfox/id47.html
    is an interesting article which supports the point that India has far too many cattle (for the amount of feed available), and that politically-exploited religious dogmas are standing in the way of remedying this.


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