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Science at the bleating edge

Filed under: — gavin @ 7 July 2009

Many of you will remember our pioneering discussion of the Sheep-albedo hypothesis, where we suggested that increasing numbers of sheep would cause a cooling climate because of their impact on the ground reflectivity. Well, new observations have now added significantly more complexity to this seemingly understood situation. It has just been reported that as well as the original sheep-albedo effect, there is now evidence of a second sheep-albedo effect (smaller sheep as the world warms). That would be a amplifying effect in general, but the actual population of sheep concerned come in many colours, so the overall affect is uncertain. (There is even speculation about a third effect (the sheep lifetime albedo impact), which could go either way depending the Lamb Marketing Board advertising campaign).

Yet more evidence that the science is very woolly.

*Title taken from a comment from glen

68 Responses to “Science at the bleating edge”

  1. 51
    Vicky I says:

    I think we’ve definitely uncovered some more known unknowns here. The theories flying around our office include a spectacular debate about blondes vs brunettes.

    There’s so much potential for further research here. For example, what has been the impact on surface albedo during the summer months with Scouts and Guides moving away from green canvas ridge tents, to white bell tents?

    So many hypotheses, so little time…

  2. 52
    Jeffrey Davis says:

    Great. The wife already accuses me of wool gathering when I read this site.

  3. 53
    Lynn Vincentnathan says:

    I don’t know, this sounds like it could lead to the “wool ball” effect.”

  4. 54
    Colin says:

    If more sheep impact the albedo enough to cause a cooling effect, wouldn’t more solar panels (which absorb light–especially in high albedo deserts) cause a global warming impact.

    I did some really back of the envelope math on this before (e.g. Ast 101 level greenhouse effect model),and converting all of the u.s.’s electricity production to solar, and assuming all panels were placed in the desert, would cause a small, but significant increase in equilibrium temperature.

  5. 55
    Bert Oleander says:

    Does this have any chance of being considered in the cap and trade legislation? Could I maybe acquire a herd or three and sell credits?

  6. 56
    Lynn Vincentnathan says:

    Again, we are not taking a holistic approach on this. What about other species?? Like the Arctic wolf spider, which is getting bigger in a warming climate (at least the females) — see: (below)

    “Climate change and sexual size dimorphism in an Arctic spider”

    Abstract: Climate change is advancing the onset of the growing season and this is happening at a particularly fast rate in the High Arctic. However, in most species the relative fitness implications for males and females remain elusive. Here, we present data on 10 successive cohorts of the wolf spider Pardosa glac-ialis from Zackenberg in High-Arctic, northeast Greenland. We found marked inter-annual variation in adult body size (carapace width) and this variation was greater in females than in males. Earlier snowmelt during both years of its biennial maturation resulted in larger adult body sizes and a skew towards positive sexual size dimorphism (females bigger than males). These results illustrate the pervasive influence of climate on key life-history traits and indicate that male and female responses to climate should be investigated separately whenever possible.

    And they might be getting more numerous — see:

    This may mean a positive feedback, since they appear somewhat darker (than white snow or sheep), or at least they might cause an arctic amplification effect, and this might overwhelm the negative feedback of shrinking sheep.

    And we’re not talking arctic wolf spiders in sheep’s clothing.

  7. 57

    Ah, it’s truly summer …

  8. 58
    Michael Hauber says:

    Don’t you know that the Vikings had tiny sheep about 3 inches high when they colonised Greenland. Therefore it is impossible that sheep are getting any smaller today.

  9. 59
  10. 60

    #51 Vicky I

    “So many hypotheses, so little time…”

    I’m all for further study of both blondes and brunettes. This is an area of scientific interest.

    The examination of species differences and potentials regarding atmospheric/climate heating and cooling based on short and long term environmental changes combined with internal natural variation and external forcing could net important discoveries.

  11. 61

    EL writes:

    If you have a large number of stations being shutdown in warmer climates, would the trend not show colder figures?

    The average in a given grid square would remain about the same.

  12. 62
    Chris Winter says:

    Ha! And you people keep saying that wethers is not climate. ;-)

    To quote a popular SF franchise:

    The Master: “Woolly thinking, Doctor.”
    The Doctor: “Yes, but it feels so comfortable worn next to the skin.”

  13. 63

    Re: #48

    El, there is a new angle on this. A retraction is being published in the J. Irreprod. Results, Vol. 243, in press.

  14. 64
    David B. Benson says:

    The wool is being pulled over your eyes…

  15. 65
    Spudder says:

    Suggest that everyone paint their roofs white starting with the folks in North America.

  16. 66

    Great post–but from the title, I expected a serious treatment of the denialosphere’s latest. Of course, this was a lot more fun–even if it hardly qualifies as a “maunder minimum.”

  17. 67
    jayskew says:

    Apparently Norstrilian several-ton legless sheep will evolve from Australian sheep as the climate warms….

  18. 68
    Hank Roberts says:


    I _really_ miss the previous blog comment layout in which the FIRST THING at the top of each comment was the commenter’s name and timestamp.

    It used to look like this:
    # raypierre Says:
    28 April 2006 at 7:10 AM

    What’s at issue is not just a matter of making mistakes…..