Might the predictions of climate change be wrong? Or do you believe on faith!

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This topic contains 13 replies, has 8 voices, and was last updated by  Unseen 5 years, 3 months ago.

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  • #616

    Unseen
    Participant

    Let me start by saying I’m not a climate denier. I think the climate scientists predicting changes due to human-related causes seem to be right. The only knowledge—if you can call it knowledge—on which I base this is the fact that so many scientists seem to agree on this.

    However, let’s be clear. Climate change isn’t a fact the way the boiling point of water is a fact or even the way evolution is a fact.

    What the scientists agree on is the output of climate models. But computer models don’t have a spotless record. Not even close. In fact, their record is anything but stellar.

    A recent example: A few days ago the meteorological models predicted a record hot day here in Portland, after morning clouds that were supposed to burn off early in the day, it was supposed to go up to 100F and possibly as high as 103F. Well, contrary to the models the meteorologists used, the clouds never burned off and the temperature never got out of the low 90’s.

    Economic models are virtually useless because they are so frequently wrong. And the reason why economic models and models in areas outside economics so often fail has to do with chaos theory—the so-called butterfly effect—whereby a small error or even rounding a number off can turn out to propagate huge errors and bad predictions.

    Of course, another way to put the butterfly effect is to say “garbage in, garbage out.” It’s just that with chaos theory we now know how small that garbage can be and still make a model useless.

    Keep in mind the butterfly effect and the fact that the climate scientists compiled a mind-bogglingly huge quantity of data. What if some of that data is a little bit off?

    It seems to me that for many people, belief in human-caused climate change has become a de facto article of faith. They have lost the ability to hedge their bet by adding even a little realism, “of course, it’s based on computer models and computer models are often wrong.”

    #630

    Gallup’s Mirror
    Participant

    “Keep in mind the butterfly effect and the fact that the climate scientists compiled a mind-bogglingly huge quantity of data. What if some of that data is a little bit off? It seems to me that for many people, belief in human-caused climate change has become a de facto article of faith.”

    Faith is necessary when there is lack of evidence. We have evidence for climate change in the past. The IPCC allows for error, indicating throughout its descriptions of climate change the probability that an assertion is correct and confidence in the accuracy of the supporting data. See the included text below for an example.

    As far as models projecting the future climate based on past and current trends, sure they could be wrong. This is part of any forecast. A typical weather report indicates probability of various conditions. A lottery gives the odds of winning. An estimate of future lifespan is based on past and current health of the patient.

    I don’t take weather reports on faith. I accept that tomorrow there is a 20% chance of rain, based on the best information available, and plan accordingly. If I care to check the data, I can see approaching rain clouds on weather radar maps.

    A prediction does not have to be certain to be useful in making plans. In a weather model predicting rain, I will not put sealer on my driveway tomorrow. In a model predicting sunshine, I will. I can prepare for both outcomes. In a powerball drawing giving one chance in fifty million of winning, I’ll hold off on hiring a butler until after the drawing.

    And so on.

    ——————-
    Ocean warming dominates the increase in energy stored in the climate system, accounting for more than 90% of the energy accumulated between 1971 and 2010 (high confidence), with only about 1% stored in the atmosphere. On a global scale, the ocean warming is largest near the surface, and the upper 75 m warmed by 0.11 [0.09 to 0.13] °C per decade over the period 1971 to 2010. It is virtually certain that the upper ocean (0−700 m) warmed from 1971 to 2010, and it likely warmed between the 1870s and 1971. {1.1.2, Figure 1.2}

    Averaged over the mid-latitude land areas of the Northern Hemisphere, precipitation has increased since 1901 (medium confidence before and high confidence after 1951). For other latitudes, area-averaged long-term positive or negative trends have low confidence. Observations of changes in ocean surface salinity also provide indirect evidence for changes in the global water cycle over the ocean (medium confidence). It is very likely that regions of high salinity, where evaporation dominates, have become more saline, while regions of low salinity, where precipitation dominates, have become fresher since the 1950s. {1.1.1, 1.1.2}
    (Source: IPCC – Climate Change 2014 – Synthesis Report Summary for Policymakers)

    #637

    SteveInCO
    Participant

    I suspect that a large part of what’s going on is that the system is not fully understood. You cannot accurately model something if you don’t account for everything that effects it, and you can’t do that if you don’t even know everything that effects it.

    We just saw (over in Sunday School) that someone has suggested the Sun’s sunspot cycle is much more complicated than previously supposed. A minimum like we had ca. 1700 will have a huge effect on the weather here, and that effect could span decades.

    Would it make anthropogenic climate change untrue? Depends on what you mean by that question.

    It will swamp the warming trend for a while (so if that’s what you mean by the question, the answer is “yes, it makes it untrue”), so people will be able to point at the cold weather outside and say “see! Damn scientists! I’ll bet they’re wrong about evolution too!” It will be difficult to get them to understand it would be even colder outside were it not for the CO2.

    Does human-released CO2 have an upward effect on heat retained by the earth? Undeniably. (So if that’s what you mean when you ask questions about whether AGW is shown falsee, the answer is “no, it’s still true.”) [I will hedge though… some of the effects could cause short term local cooling; e.g., imagine what would happen to Europe if one of those effects were to kill the Gulf Stream.] Does that mean the Earth *will* warm up? Not necessarily, as other factors (such as solar variability) will come into play as well.

    Actually an upcoming minimum, if mild instead of as severe as what happened in 1700, might be good news, as it gives us time to bring non-CO2-generating power generation on line. Practical fusion is still a ways off. In spite of constant incremental improvements, batteries still suck too much to make solar truly practical for many applications (plus, widespread solar could effect the biosphere by denying it a good percentage of the sunlight that underpins it). Ideally the two effects (AGW and solar minimum) will cancel, and we have a chance to pursue developing economical alternatives rather than having to run in crisis mode and sink money into methods that must be subsidized.

    Meanwhile we in Colorado are enjoying the effects of El Nino. And I do say “enjoying” for the most part; it’s a relief to not have to worry about burning to a crisp the next time some shit-for-brains throws a lit cigarette out his car window. When someone complains about the rain we’ve had here (probably no more than the PNW gets normally, and let’s leave aside the Olympic peninsula, where even concrete grows mold), I tell them it’s better than burning.

    #641

    Unseen
    Participant

    I don’t take weather reports on faith. I accept that tomorrow there is a 20% chance of rain, based on the best information available, and plan accordingly. If I care to check the data, I can see approaching rain clouds on weather radar maps.

    A prediction does not have to be certain to be useful in making plans. In a weather model predicting rain, I will not put sealer on my driveway tomorrow. In a model predicting sunshine, I will. I can prepare for both outcomes. In a powerball drawing giving one chance in fifty million of winning, I’ll hold off on hiring a butler until after the drawing.

    A lot of money will be diverted and a lot of lives adversely affected based on these climate models, so it’s rather important that they be right. We are asking countries in the developing world to develop much more slowly in order to accommodate possibly flawed calculations. Even if we were to bear the brunt of such changes, even asking countries like China and India and Brazil to bear some of the load will place an unfair burden on them. Unfair, because we gave ourselves such a huge headstart by using fossil fuels like there was no tomorrow. Like there was an inexhaustible supply.

    While only a crazy science denier could possibly maintain that human activities have no effect on climate change, it may be that the effect is a much smaller part of the causal system than climate scientists believe based on their models. What do we tell all those affected by our futile efforts then? Oops!!!?

    #642

    Unseen
    Participant

    I suspect that a large part of what’s going on is that the system is not fully understood. You cannot accurately model something if you don’t account for everything that effects it, and you can’t do that if you don’t even know everything that effects it.

    Of course, that’s my point. A computer model is only as good as what you put into it: garbage or gold. And then there’s the effect of chaotic behavior on the model, which as I understand it is virtually unpredictable. If some scientist rounded a number somewhere, it turns out that can have a dramatic effect on the output of the model. What about a bad measurement by a defective or uncalibrated device?

    As I’ve said, I make no claim that the climate models used to support anthropogenic climate change are wrong. I just think that the general public places more faith in them than is deserved.

    While “hindcasting” is used to determine the worth of a model (e.g., could the model have predicted the inception and duration of one of the ice ages) even this can do no more than increase our confidence. It’s not proof that the model can never get things wildly wrong. We forget that a climate model, at its heart, is nothing more than a mind-bogglingly huge mathematical formula. The exact opposite of E=MC2, the very model of a formula which is simple, elegant, easily understood, and testable on a reasonable timescale.

    #645

    Syd Andrews
    Participant

    I think there is a point that is being missed.

    So far, I think we all agree that the current predictions of our future climate are based upon models. And those models may not be as accurate and reliable as we’d like them to be. So there is a chance, albeit a small one, that the whole “global warming” concept could be completely wrong and humans will be just fine.

    However, the “stakes” on our prediction are high. If our models are COMPLETELY wrong or if there is some source of data that we have no way of knowing about and adding in to our predictive models, then maybe we’re all just fine and this “global warming scare” is a laughable waste of time. Or, on the other extreme of outcomes, our predictions are actually underestimating the outcomes of global warming and we have a “runaway greenhouse effect” and life on this planet undergoes a mass extinction, possibly eliminating the human race.

    Now I think that both of those “extreme ends” of the spectrum of possible outcomes are unlikely. But I also think that humanity should err on the side of caution. If we (as humans) have to spend more money, time, and effort to implement measures to stave off a possible disaster, then so be it. And if it turns out that the disaster wasn’t going to happen after all, so what? In that outcome, we’re all still here and alive. But if we say, “Oh, maybe it won’t happen” and do nothing, we are banking on that chance that the current models are completely incorrect. And if our gamble is wrong, then we’re screwed.

    I think it is in the best interest of humanity as a whole to continue to pursue methods of power generation that don’t pump more ancient carbon into the atmosphere. I think it is in our best interest to reduce (and ultimately eliminate) our dependence on fossil fuels both in developed and also in developing regions of the world. I think that even if everything the climate models predict turns out to be completely incorrect, we would be better off on this planet if we still do what we can to change how we use resources.

    Put simply, if climate change is “wrong” but we bet that it is “right”, the end result is that humans are still around and prospering. If climate change is “right” but we bet that it is “wrong”, then we’re doomed.

    #647

    PopeBeanie
    Moderator

    I don’t think unprecedented rising CO2 level is just a butterfly, and I know this graph isn’t from bad data:
    Recent CO2 Levels and Ocean Acidification

    This one covers almost a half-million years of CO2 on Earth (and note that we’re now over 400ppm):

    CO2 ice core data 800k years ago to present

    An excerpt from scripps.ucsd.edu

    These suggest that the last time atmospheric CO2 was over 400 ppm was at least as far back as the Pliocene, three to five million years ago, before humans roamed the earth and when the climate was considerably warmer than today.

    • This reply was modified 8 months, 1 week ago by  PopeBeanie. Reason: updated the CO2 ice core graphic (800k year history)
    #648

    DrBob
    Participant

    First, let’s dispense with the nonsense over the term “model”. The climate deniers squalk about “it’s just a model” the way evolution deniers squalk about “it’s just a theory”. Modeling is how we do science. It’s part of the “scientific method” if you like that terminology. You can’t reject the process of theorizing or modeling without denying science completely.

    Second, let’s dispense with the nonsense over nonlinear dynamics and complexity (the “butterfly effect”). Physical processes that can be described by nonlinear equations that have a feedback component often show sensitive dependence on initial conditions. That makes it difficult to predict whether it will rain in two weeks on Tuesday morning in your city.

    That’s not climate, however. The climate models may fail in terms of predicting how much hotter it will get in Mexico City on a given year, and yet still be completely sound when it comes to how the Earth’s climate will progress over 30 years.

    There are things that we don’t understand fully. It’s not completely clear how much melting of arctic permafrost will accelerate climate change through methane releases. Clouds and cloud reflectivity in different frequencies are really complex. Ocean current changes aren’t perfectly understood. The truth is, by dumping tens of billions of metric tons of carbon into the atmosphere each year we’re conducting a large, uncontrolled experiment with the planet. There will be continued revisions as we collect more data from this uncontrolled experiment.

    However, at this point there’s about as much data supporting driven climate change as there was for evolution in the 1950s, or for cigarettes causing cancer in the 1980s. It has crossed the threshold where denying the fundamental conclusion is the realm of science-denying bias and not rationality.

    The questions now for science are not whether this is happening, but rather on just how bad this is going to be. There’s an extent to which “how bad” is still an open question, but the evidence coming in is more along the lines of “really bad” to “catastrophically bad” rather than “only sorta bad”. There’s also debate over who will end up with catastrophically bad. So, for example, there’s still a question about whether and when the Great Plains of the U.S. will be turned into a dust bowl, or how much colder northern Europe will become if/as the Atlantic conveyor breaks down.

    We are asking countries in the developing world to develop much more slowly in order to accommodate possibly flawed calculations.

    No, we’re really not, or at very least that’s not clear. The transition to alternate energies is totally doable without significant damage to the developed world, and indeed with net long-term economic gains. See for example the work by the engineering team at Stanford, which assumes only current technologies: http://news.stanford.edu/pr/2015/pr-50states-renewable-energy-060815.html . There’s no reason necessarily to believe that the developing world can’t follow suit, though this gets into complex economic and political issues more than science.

    Honestly, the way we are holding the developing world in debt peonage (along with some of the developed world, like Greece) likely has a much larger impact on development rate than any form of carbon tax will.

    • This reply was modified 5 years, 3 months ago by  DrBob.
    #650

    Unseen
    Participant

    I think it is in the best interest of humanity as a whole to continue to pursue methods of power generation that don’t pump more ancient carbon into the atmosphere.

    This is why I’m a proponent of continuing to develop and put in place thorium nuclear reactors.

    #658

    .
    Spectator

    I started the group on climate change, and time permitting I’m actively in the process of trying to put together podcasts to educate people on these sorts of questions. I really think that there’s not a lot of clear and concise education to the public about not only how to read and interpret the data but what the implications ACTUALLY are. Short of being a scientist yourself it’s hard to convey in a few short sentences….

    Unseen your questions is valid, but here’s my short answer to you:

    RE: However, let’s be clear. Climate change isn’t a fact the way the boiling point of water is a fact or even the way evolution is a fact.


    What we do know and is undeniable is that anthropocentric activities have caused the CO2 in the atmosphere and the hydrosphere to exceed levels that are unprecedented within the last 800,000 years ago (data of which we’ve been able to analyze and extrapolate meaningful numbers), and we do know that this is causing a global energy shift and increased global temperature. The current measurement of CO2 in the atmosphere is over 400ppmv which is a dangerous level of CO2.

    The effects are profound and are happening right before our eyes.

    #666

    Gallup’s Mirror
    Participant

    A lot of money will be diverted and a lot of lives adversely affected based on these climate models, so it’s rather important that they be right.

    Yes indeed.

    The challenge is that it’s impossible to predict complex outcomes with certainty. The best we can do is estimate the odds of different scenarios coming to pass and assess the quality of the supporting data. Policymakers are well advised to give the most credence to the ‘high confidence’ and ‘virtually certain’ aspects of the report.

    [If we are wrong] what do we tell all those affected by our futile efforts then? Oops!!!?

    Oops would sum it up.

    The outcomes of different scenarios span the next 85 years, so by 2100 the predicting scientists will be dead and spared having to admit any mistakes. But it seems unlikely they are that far off, given the accuracy of IPCC temperature predictions since 1990, which were made using less data.

    #671

    Unseen
    Participant

    The transition to alternate energies is totally doable without significant damage to the developed world, and indeed with net long-term economic gains.

    I’m not clear on what you’re saying. When someone says something “is doable,” all too frequently they are assuming a concordance of mind and purpose that would be virtually unprecedented and realistically unattainable in any world like the one we’re living in. Politically speaking I mean. Heck, look how hard it is to get Americans to agree on a plan, much less a bunch of countries with competing, conflicting, and incompatible values and outlooks.

    #704

    Simon Mathews
    Participant

    I agree with @drbob that climate shouldn’t be considered the same as weather in the sense that general trends over time are easier to model as statistical noise is lessened. So whilst we cannot say whether it will rain next Tuesday we can say with some confidence that polar ice caps will continue to melt (for example).

    In terms of solutions, I’m reminded of a passage in Jurassic Park (the book, not the film) where a character says “We need to act to save the planet” and the scientist replies “The planet can take care of itself, we need to act to save ourselves.” His point was that in the long term whatever we do to the planet we will not destroy it. Earth has been around billions of years longer than we have and can adjust to anything we can throw at it. However if we’re not careful there’s a very good chance we’ll render it uninhabitable for our species.

    I’m also skeptical of our ability to control climate change. It is often impossible to predict what the effects of our “control” mechanisms will be. For example an attempt to control an animal population by culling can often lead to other animals taking advantage of the sudden lack of predators and running rife. We may take steps to alleviate (for example) the melting of polar ice caps and end up causing worse havoc. As Bob says we are in the middle of a huge experiment with our surroundings.

    I know this view is a negative one and makes it seem like we shouldn’t bother doing anything. That’s not quite my outlook. I recycle and re-use shopping bags and all the little sensible things we can do. I think renewable energy sources are an admirable goal, though how achievable is another matter. I just worry about our ability to understand what global effects our behaviour has.

    #707

    Unseen
    Participant

    I’m also skeptical of our ability to control climate change. It is often impossible to predict what the effects of our “control” mechanisms will be. For example an attempt to control an animal population by culling can often lead to other animals taking advantage of the sudden lack of predators and running rife.

    For example, there are people who lament that domestic cats kill so many birds and small animals. They actually propose getting rid of cats. However, one reason the cats are there is that they have taken over for natural predators who were driven off by human encroachment into their habitat. A lot of predators are shy of humans. Cats, obviously, are not. If we got rid of domestic cats, would the bobcats, wolverines, cougars, and wolves come back? Some changes are irreversible, unfixable. And would we really want wolf packs and cougars prowling our housing developments?

    • This reply was modified 5 years, 3 months ago by  Unseen.
    • This reply was modified 5 years, 3 months ago by  Unseen.
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