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Climate Change 

March 14, 2008

Ignoramus et ignorabimus

The new California Academy of Sciences is headed toward completion, and the process of preparing the new facility, readying the exhibits, and moving the more than 20 million specimens in our natural history collections is keeping many of us very busy. You can find out more about the happenings here, and view a very nice video here.

Nevertheless, science goes on. While discussing our planned exhibit on climate change with some external designers a couple of weeks ago, one of them commented on the topic of “uncertainty.” She said that we should avoid the word at all costs because the general public already does not trust scientists, and that everytime they hear that particular word, it reinforces the notion that we scientists don’t know what we’re talking about (“You can’t even predict the weather 12 days from now!”). Is this true? Please send comments if you have any! Anyway, nothing could be farther from the truth. Let me tell you, Uncertainty is part of the beauty of the Universe.

When we (scientists) use the term Uncertainty, we mean either unknown, not understood, or unknowable. Let me attempt to explain using climate change science as an example. There is uncertainty in our predictions of the future’s climate because there are unknown quantities in our reasoning. Some of these quantities include important feedbacks in climate change processes that we simply have not recognized. For example, who would have thought ten years ago that as ice sheets melt, that they would lubricate and accelerate their own slide towards the sea? Other important unknowns include all the human ones. How quickly will the developing world increase its carbon emissions over the next 100 years? How much international economic cooperation can we all count on? Then there is the “not understood.” There are processes and phenomena whose science still escape us. E.g. we know that clouds play a role in climate, but will it be an important role as the planet continues to heat up? Will it be a cooling role? I don’t know, though there are some very clever people out there trying to figure it out.

And then there is the unknowable. The notion that once we’ve understood the mechanisms at work in the world, and have measured the right things, that we will be able to predict the future the way that we predict the ticking of a clock, is a deep-rooted consequence of the Newtonian and Cartesian revolutions. It is a dangerous hubris. The Universe does not work that way. The revolution of quantum physics told us that the Universe is random at the smallest scales. More recently, areas such as Chaos Theory and Catastrophe Theory have revealed that even the most innocent looking phenomena, such as weather(!), can be full of surprises. Take a look at this little equation.
X(t+1) = rX(t)(1-X(t))

logistic_chaos.jpgIt simply tells us that the size of an animal’s population, X, at time t+1 is the product of the population’s size at time t, multiplied by the typical birthrate of the species (r). If r is 3 (members of the population have 3 offspring per breeding season in excess of deaths), then we see that one can predict population size well into the future; it’s a simple cycle (upper graph). Sir Isaac is happy. Now, however, let’s say that r is 3.6 (I know, you can’t have three and a bit kids, but just indulge me). At this value, and for most values beyond, population size is effectively unpredictable! There’s no randomness here folks. This is a deterministic but inherently unknowable system! Welcome to Chaos Theory. And welcome to weather prediction. In this case, Uncertainty is not the result of ignorance, it is part of the inherently unknowable Universe. The system cannot tell us where it’s headed if the system itself doesn’t know. Beautiful.

Btw, if any of you yougsters out there think that you can predict where the second population is headed, then you deserve a Fields Medal (let me know; I’ll nominate you). In the next posting we’ll get back to our modeling, touch on Catastrophe Theory, and chat about tipping points.

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Filed under: Climate Change — Peter @ 7:32 am

4 Comments »

  1. EMISSIONS TRADING GOES GLOBAL
    More governments and multi-national companies are using emissions trading as a business weapon to fight climate change.

    The carbon market was worth $64 billion last year and is expected to double this year.

    Cap and trade schemes enable energy-intensive industries to buy permits to emit greenhouse gases such as carbon dioxide, which is produced from burning fossil fuels.

    The European Union launched its cap and trade scheme in 2005 while New Zealand will launch a similar initiative this year. Canada and Australia propose to launch schemes in 2010. And the US senate is scheduled next month to debate details of a proposed Federal US climate change bill that will include cap and trade.

    As well, countries and companies can trade carbon offsets under three, UN-led Kyoto Protocol schemes. Richer countries can earn emission permits by investing in cuts in greenhouse gases in less wealthy countries.

    The three sub-schemes of the Kyoto pact included the Clean Development Mechanism (CDM) whereby rich countries can invest in clean energy projects in developing nations. Joint Implementation (JI) in which rich countries invest in clean energy projects in former communist countries, and Assigned Amount Units (AAU) that allows signatories to trade surplus emissions rights.

    For more information, please visit http://www.earthcharterfoundation.com and http://dailyplanetmedia.com

    Comment by Eve Earth Charter Foundation — May 28, 2008 @ 1:23 am

  2. Hi Peter,

    I read this article from the Wall Street Journal and was aggravated by it. I would be interested in hearing how you would respond:

    Global View
    Global Warming as Mass Neurosis
    By Bret Stephens
    743 words
    1 July 2008
    The Wall Street Journal
    A15
    English
    (Copyright (c) 2008, Dow Jones & Company, Inc.)
    Last week marked the 20th anniversary of the mass hysteria phenomenon known as global warming. Much of the science has since been discredited. Now it’s time for political scientists, theologians and psychiatrists to weigh in.
    What, discredited? Thousands of scientists insist otherwise, none more noisily than NASA’s Jim Hansen, who first banged the gong with his June 23, 1988, congressional testimony (delivered with all the modesty of “99% confidence”). But mother nature has opinions of her own. NASA now begrudgingly confirms that the hottest year on record in the continental 48 was not 1998, as previously believed, but 1934, and that six of the 10 hottest years since 1880 antedate 1954. Data from 3,000 scientific robots in the world’s oceans show there has
    been slight cooling in the past five years, never mind that “80% to 90% of global warming involves heating up ocean waters,” according to a report by NPR’s Richard Harris. The Arctic ice cap may be thinning, but the extent of Antarctic sea ice has been expanding for years. At least as of February, last winter was the Northern Hemisphere’s coldest in decades. In May, German climate modelers reported in the
    journal Nature that global warming is due for a decade-long vacation. But be not not-afraid, added the modelers: The inexorable march to apocalypse resumes in 2020.
    This last item is, of course, a forecast, not an empirical observation. But it raises a useful question: If even slight global cooling remains evidence of global warming, what isn’t evidence of global warming? What we have here is a nonfalsifiable hypothesis, logically indistinguishable from claims for the existence of God. This doesn’t mean God doesn’t exist, or that global warming
    isn’t happening. It does mean it isn’t science.
    So let’s stop fussing about the interpretation of ice core samples from the South Pole and temperature readings in the troposphere. The real place where discussions of global warming belong is in the realm of belief, and particularly the motives for belief.
    I see three mutually compatible explanations. The first is as a vehicle of ideological convenience. Socialism may have failed as an economic theory, but global warming alarmism, with its dire warnings about the consequences of industry and consumerism, is equally a rebuke to capitalism. Take just about any other discredited leftist nostrum of yore — population control, higher taxes, a vast new regulatory regime, global economic redistribution, an enhanced role for the United Nations — and global warming provides a justification. One wonders what the left would make of a scientific
    “consensus” warning that some looming environmental crisis could only be averted if every college-educated woman bore six children: Thumbs to “patriarchal” science; curtains to the species.
    A second explanation is theological. Surely it is no accident that the principal catastrophe predicted by global warming alarmists is diluvian in nature. Surely it is not a coincidence that modern-day environmentalists are awfully biblical in their critique of the depredations of modern society: “And it repented the
    LORD that he had made man on the earth, and it grieved him at his heart.” That’s Genesis, but it sounds like Jim Hansen.
    And surely it is in keeping with this essentially religious outlook that the “solutions” chiefly offered to global warming involve radical changes to personal behavior, all of them with an ascetic, virtue-centric bent: drive less, buy less, walk lightly upon the earth and so on. A light carbon footprint has become the 21st-century equivalent of sexual abstinence.
    Finally, there is a psychological explanation. Listen carefully to the global warming alarmists, and the main theme that emerges is that what the developed world needs is a large dose of penance. What’s remarkable is the extent to which penance sells among a mostly secular audience. What is there to be penitent about? As it turns out, a lot, at least if you’re inclined to believe that our
    successes are undeserved and that prosperity is morally suspect. In this view, global warming is nature’s great comeuppance, affirming as nothing else our guilty conscience for our worldly success.
    In “The Varieties of Religious Experience,” William James distinguishes between healthy, life-affirming religion and the monastically inclined, “morbid-minded” religion of the sick-souled. Global warming is sick-souled religion.

    Comment by Maral Ruiz — July 29, 2008 @ 2:29 pm

  3. Thank you for the discussion. When it comes to climate there are many uncertainties. The problem with climate scientists and public credibility may be related to scientists becoming advocates and exaggerating. Of course government scientists are not going to tell Congress, the source of their money, what it does not want to hear. They are smarter than that!

    This may be beside the point, but I assume your reference to ice sheet sliding along lubricated by melt water refers to Greenland and Antarctic Ice sheet. Apparently that is NOT POSSIBLE See: Cliff Ollier, School of Earth and Geographical Sciences, The University of Western Australia, Crawley, WA 6009, Australia (cliffol@cyllene.uwa.edu.au) He suggests that Hansen’s models are based on a lack of understanding of how glaciers flow. Regarding clouds and positive feedback, what do you think about Roy Spencer’s observations that there is evidence of a strong negative feedback?

    I have always had a difficult time understanding positive feedback. Most of what I have been told has been that there are negative feedbacks, e.g., for every PhD there is an equal and opposite PhD.

    Comment by Don — September 1, 2008 @ 4:05 pm

  4. Climate change for the coastal region will be presented at sears building in irvine with steven and mike and the coastal asset protection team. eight pm video after the attorney speaker

    Comment by theresa — March 2, 2009 @ 11:09 am

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