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The tragedy of climate commons

Filed under: — gavin @ 7 May 2009 - (Svenska)

Imagine a group of 100 fisherman faced with declining stocks and worried about the sustainability of their resource and their livelihoods. One of them works out that the total sustainable catch is about 20% of what everyone is catching now (with some uncertainty of course) but that if current trends of increasing catches (about 2% a year) continue the resource would be depleted in short order. Faced with that prospect, the fishermen gather to decide what to do. The problem is made more complicated because some groups of fishermen are much more efficient than the others. The top 5 catchers, catch 20% of the fish, and the top 20 catch almost 75% of the fish. Meanwhile the least efficient 50 catch only 10% of the fish and barely subsist. Clearly, fairness demands that the top catchers lead the way in moving towards a more sustainable future.

The top 5 do start discussing how to manage the transition. They realise that the continued growth in catches – driven by improved technology and increasing effort – is not sustainable, and make a plan to reduce their catch by 80% over a number of years. But there is opposition – manufacturers of fishing boats, tackle and fish processing plants are worried that this would imply less sales for them in the short term. Strangely, they don’t seem worried that a complete collapse of the fishery would mean no sales at all – preferring to think that the science can’t possibly be correct and that everything will be fine. These manufacturers set up a number of organisations to advocate against any decreases in catch sizes – with catchy names like the Fisherfolk for Sound Science, and Friends of Fish. They then hire people who own an Excel spreadsheet program do “science” for them – and why not? They live after all in a free society.

After spending much energy and money on trying to undermine the science – with claims that the pond is much deeper than it looks, that the fish are just hiding, that the records of fish catches were contaminated by being done near a supermarket – the continued declining stocks and smaller and smaller fish make it harder and harder to sound convincing. So, in a switch of tactics so fast it would impress Najinsky, the manufacturers’ lobby suddenly decides to accept all that science and declares that the ‘fish are hiding’ crowd are just fringe elements. No, they said, we want to help with this transition, but …. we need to be sure that the plans will make sense. So they ask their spreadsheet-wielding “advocacy scientists” to calculate exactly what would happen if the top 5 (and only the top 5) did cut their catches by 80%, but meanwhile everyone else kept increasing their catch at the current (unsustainable rate). Well, the answers were shocking – the total catch would be initially still be 84% of what it is now and would soon catch up with current levels. In fact, the exact same techniques that were used to project the fishery collapse imply that this would only delay the collapse by a few years! and what would be the point of that?

The fact that the other top fishermen are discussing very similar cuts and that the fisherfolk council was trying to coordinate these actions to minimise the problems that might emerge, are of course ignored and the cry goes out that nothing can be done. In reality of course, the correct lesson to draw is that everything must be done.

In case you think that no-one would be so stupid as to think this kind of analysis has any validity, I would ask that you look up the history of the Newfoundland cod fishery. It is indeed a tragedy.

And the connection to climate? Here.

I’ll finish with a quotation attributed to Edmund Burke, one the founders of the original conservative movement:

“Nobody made a greater mistake than he who did nothing because he could do only a little.”

See here for a much better picture of what coordinated action could achieve.


1,401 Responses to “The tragedy of climate commons”

  1. 1401
    J.S. McIntyre says:

    re 1394: J.S. McIntyre Says (11 juin 2009 at 9:48 PM):

    ME: “So as long as the diabetes is under control, it is okay to die of a heart attack.
    Great logic! Seriously! *sarcasm off*”

    JAMES: Not sarcasm at all, but apparently a major difference in values.

    James, you have yet to demonstrate you have any ‘values’ of merit. Unless you would characterize a consistant effort to avoid owning up to anything you have to say as a ‘value’ (though, in a sense, that is a ‘value’ … just not a positive one).

    JAMES: “I have an acquaintance whose diabetes progressed to the point where he had both legs amputated.”

    My sympathies for your alleged acquaintance. Unfortunately, his plight and your wandering hypothetical have nothing to do with the focus of the discussion, no matter how much you want to stamp your virtual foot and yell “Does to!”

    But that’s okay … it’s an obvious pattern with you. If you can’t honestly address the subject at hand, you figure changing the subject will allow you breathing room … or something. Frankly, I do not understand what it is you think you are accomplishing here, but it certainly has nothing to do with an honest, open and relevant exchange of ideas.

    JAMES: “I’d rather live life than sit & watch because I’m afraid of dying.”

    We’re all going to die, James. And while your alleged friend has my sympathies, amputation does not mean your life is over. More difficult, perhaps, altered, but far from over. And heart attacks kill, unless you missed that little detail.

    This red herring, like so many you have tossed up in the series of posts between us, does little to help you, and only underscores the understanding that when push comes to shove, you seem incapable of actually engaging anyone openly if they happen to disagree or take issue with what you have to say.

    Sincerely, what a sad way to carry on …

    ME: “And I still have a half of basketball to watch…”

    JAMES: Explains a lot, that does.

    Really? And what would that touch of innuendo ‘explain’, pray tell? Do you have something against physical activity, or the enjoyment thereof? Are you trying to suggest that because someone draws pleasure from watching great athletes competing, he or she is somehow lacking in some fashion? I find that odd, even contradictory, particularly given just a moment ago you were singing the praises ‘living life’.

    [Response: This conversation has outlived all usefulness. Comments are now closed. – gavin]


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