Projections for the future: really conservative or just unreliable?

Before The Flood - Jason Box

In the documentary “Before the flood” there was this scene in which Leonardo DiCaprio was in a conversation with Jason Box on a glacier in Greenland. This came after a scene of Leonardo DiCaprio in his earlier days when he still was thinking that global warming could be solved with small individual actions, like changing light bulbs. Then an ominous sounding voice-over:

But it is pretty clear that we are way beyond that point right now. Things are taken a massive turn for the worse.

Cue in a calving glacier, followed by Jason Box saying:

“We keep finding things that aren’t in the climate models. They are used to project the future. So that tells me that the projections for the future are really conservative.”

That was interesting. I heard many times before that climate models are “too conservative”. I understood that the models were cautious and underestimated things, therefor it is expected that it would get worse than the models showed. That is also how I understood the statement from Jason Box. I am pretty sure that this statement was not being used as having some innocent meaning in this one-sided documentary, immediately after the statement that “things are taken a massive turn for the worse”…

Until now I didn’t understand the reason for this “conservative”-claim. Luckily, this time the reason is mentioned: many things are still being found that have to be put into the models. Okay, I could somehow understand this kind reasoning.

I have no problem agreeing that many things are not in the climate models yet and that scientists keep finding things that are not accounted for in the models. That is the consequence of the Earth, and its climate, being a complex, coupled and chaotic system. In such a system it is not unusual that some things are not accounted for.

But how could we then, in such a system, be sure that the projections for the future are “really conservative”? As far as I know it cuts both ways. We don’t know the things we don’t know. Maybe these will confirm the theory, maybe not.

If it is true that we keep finding things that aren’t in the climate models, then the conclusion would rather be that the projections for the future are not really reliable at this point, especially when it comes to policies. We can not assume a direction if we keep on finding things that are not accounted for.

From previous experiences I know that such claims about the performance of the models concerning the ice melt don’t mean much. The best example was the one in which was stated that the climate models were lagging far behind the (sea ice) observations, until reality finally caught up and the opposite was claimed. I expect that this “projections for the future are really conservative”-claim is also just the same hyperbole.

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4 thoughts on “Projections for the future: really conservative or just unreliable?

  1. Climate Otter

    I believe it is true that many new things are being found which are not accounted for in the models. And many of those things are Negative Feedback mechanisms.

    But they are not going to acknowledge that fact. The claim that ‘the models are conservative’ seems nothing more than a specious attempt to account for science that doesn’t toe the AGW line. The claim allows them to skip over the contradictory facts by just saying it is ‘new science’ and the public never hears more than that. (a bit incoherent, sorry, very early in the morning)

    Reply
  2. poitsplace

    Its an amusing bait and switch. First we’re told to believe the consensus…then we’re told the consensus are likely wrong and things are far worse. So basically what we’re supposed to believe from this movie is that we’re not really supposed to trust the experts but the fear mongering, doomsday cultists of the greens. Perhaps that sounds a bit harsh. Is there someone else we’re supposed to believe?

    Oh yes, things are certainly different…its just that almost across the board the changes are lower than expected by models. Emissions are following near the top level “if we went crazy” projections. Actual atmospheric levels are following the “what if we did nothing” levels. And temperatures are following the “what if we stopped 100% of carbon emissions in 1997” path. Anyone that takes the time to actually look at the sorts of extreme weather events finds no meaningful change or pronounced reductions. The earth is greening, not dying. About the only thing that seems to be changing faster than predicted is sea ice in the arctic, which suppresses almost all life, save a tiny number of species like some seals and polar bears (Note: I did not say its lack is causing their numbers to drop)

    But in the end it all comes down to sea level…really. If there’s so much extra heat going into the system, especially with the ocean absorbing extra to conveniently hide what warming there has been, then sea level rise would be significantly higher from thermal expansion. And if the ice sheets really are going through significant mass changes resulting in more water going into the ocean…well that too should raise sea level. But there isn’t any sea level rise measured in any of the hundreds of tide gages across the planet. Each of the hundreds of gages are independently falsifying the claim that there is some kind of radical change happening. It is not “worse than we thought”. It is “better than the IPCC ever hoped it could be”.

    Reply
    1. trustyetverify Post author

      I don’t think it is a bait and switch. As far as I know, the consensus is about temperatures rising and humans having something to do with it.

      The issue here is a bit different: the models (already being alarmist) are assumed to be “conservative”. Meaning: Oh! My God! It is worse than we thought!

      Reply

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