Cross Post: Kesten Green – Forecasting climate in Paris: Ignoring the Golden Rule

The global political and media elites descending on Paris for talks on climate policy might want to consider the Golden Rule of Forecasting.

The Golden Rule derives from many decades of experimental research on forecasting across diverse fields and all kinds of forecasting problem. The Golden Rule of Forecasting “requires forecasters to be conservative by forecasting in a way that is consistent with cumulative knowledge about the situation and about forecasting.”

Ignoring the Golden Rule has important practical consequences: The size of forecast errors is typically increased by more than 40%.

The Paris climate talks are predicated on the dangerous manmade global warming scenarios and projections of the UN’s Intergovernmental Panel on Climate Change (IPCC). These projections are being treated as forecasts by the policy makers and media attending the Paris talks.

In anticipation of the Paris talks, Scott Armstrong and Kesten Green delivered a paper at this year’s International Symposium on Forecasting assessing whether the IPCC’s procedures are consistent with the Golden Rule. They found that the IPCC’s procedures violated all 20 of the relevant Golden Rule guidelines.

The abstract and slides of their paper, titled “Are dangerous warming forecasts consistent with the Golden Rule?” are available from ResearchGate, here. A supporting flyer is available, here.

Originally posted at Forecasting Principles.

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7 Responses to Cross Post: Kesten Green – Forecasting climate in Paris: Ignoring the Golden Rule

  1. Elizabeth (Lizzie) B.

    As if they care.

  2. Rafe

    This tells the story (the first figure) but again, who cares?

  3. Bruce of Newcastle

    Riccardo posted this fine link yesterday:

    FLASHBACK: ABC’s ’08 Prediction: NYC Under Water from Climate Change By June 2015

    That is the US ABC not our local one, but the forecasts are so lurid and so nutty it is fun to compare them with how things really turned out.

    Meanwhile they’re at it again:

    Apocalyptic forecasts increase as climate change conference draws near

    And it has been going on since the whole caravanserai started:

    Fifteen Foolish Forecasts: How did environmentalists get it so wrong on Earth Day 1970?

  4. Rafe

    A bit more on the failure of the climate models, essentially due to the fact that correlation between x and y does not necessarily mean that x causes y (or vice versa).

    Consider a graph of your age and your height. There will be a very satisfying correlation until you stop growing. We know enough about the actual mechanisms of growth so that the correlation is not regarded as causation, although if we were substantially in the dark about the real factors at work, and the research project was only being conducted during your own childhood there would be a great temptation to cling to the correlation and expect growth to continue. How long would that delusion last. Quite a long time in the case of the global temperature.

    What about the correlation then? How to explain that? Quite likely the models were built during the period 1980 to 2000 when by unhappy accident the temperature and the CO2 increased side by side. So the models “worked” during that time, in the way that models of age and height would work up to a point shortly after puberty. After that you have to look for other factors that influence global temperature/human height.

  5. egg_

    What’s the flying boulders forecast?

  6. egg_

    There’s also the margin of error (/tolerance) in measurements and thus also predictions, which they haven’t published since AR3?

    Teh AGW ‘signal’:
    0.3C/decade ±100% (AR1)
    0.15C/decade ±100% (AR3?)
    Now ‘masked’ by multi-decade cooling at the Pole?

  7. gabrianga

    Must book eye test.

    Thought at first you were referring to Turnbull’s Goldman rule

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