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Study predicts imminent irreversible planetary collapse

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Re: Study predicts imminent irreversible planetary collapse

#71
post #67

Earlier quoted context omitted.

You are ktizo both have the same misconception. Perhaps this explains your belief in the value of models. Those formulas are not models! They are exact mathematical representations of a phenomena! A model by it's nature can not include everything, they include everything possible of course, but the world is too complex for them to include everything, so they must estimate. If you have a feedback loop with the real wo…

Those formulas are models. They describe the world and can predict it's behaviour, but can also break down under certain conditions. For example, what happens when I put 240V across a regular 20Ohm resistor? According to V=IR you get 12A running through it - but I doubt you'll get that for very long. By your argument, V=IR must then be a "model" and is useless, with no predictive power, etc, etc. In practice, the onl…

No, those formulas are exact, you are just using them incorrectly.

You think V=IR describes a resistor, it does not. It describes electricity. So it's not surprising that when applied to a resistor it doesn't work. You are trying to model a resistor, but you are not including everything in your model, so it fails.

Which is exactly what I'm warning about.

> By your argument, V=IR must then be a "model" and is useless, with no predictive power

V=IR is not a model. Using it to describe a physical resistor is a model.

Suppose I never touched a real resistor in my life, and the only information I had was an understanding based on some other law that V=IR. Now I want to use that information to predict what a resistor will do. I will fail - among other things it doesn't take into account inductance or capacitance.

Which is why it is very very important to know what your equation describes. You thought that V=IR completely describes a physical resistor, when it does not.

Now you know why it's incredibly dangerous to try to learn anything from a model. If even something as simple as Ohm's law can be confusing, imagine how many error a model with hundreds of equations has.

Re: Study predicts imminent irreversible planetary collapse

#72

I think we don't know the long term effects of the things we are doing. But the usual cure people propose, a massive expansion of government, is worse than the disease. It will ultimately lead to more wars and an end to dealing with threats to our existence. But doing nothing is not viable either. We need to get control of the planet. We simply cannot just let the next ice age or global warming occur. This sort of th…

Last I checked, we haven't had a civil war in a while. If we had a decently sized "massive expansion of government" on, say, a planetary scale (for a planet-sized problem), wouldn't that therefore lead to less wars?

Since government is creating massive problems already, such as the global debt crisis, I really don't think all encompassing planetary government is a good idea at all.

People seem to think nothing could ever go wrong with such a concept. But history tells another story about government. We've had some very bad totalitarian governments. I'd rather not trust any single organization that will never face any competition.

I'm not saying its a bad idea to coordinate with other countries on specific issues. That's what treaties are for. Even there, some pretty bad ideas can be agreed upon. At least countries can leave a treaty that proves to be a disaster.

Re: Study predicts imminent irreversible planetary collapse

#73

Earlier quoted context omitted.

Oh for fuck's sake, just read the paper: BOX 1: Past planetary-scale critical transitions and state shifts Last glacial–interglacial transition18,24. The critical transition was a rapid warm–cold–warm fluctuation in climate between 14,300 and 11,000 yr ago, and the most pronounced biotic changes occurred between 12,900 and 11,300 yr ago24,27,30,54. The major biotic changes were the extinction of about half of the spe…

Congratulations, you've stated the theory with far more specificity and a greater degree of testability than the paper's authors managed.

I'm just paraphrasing the paper. Everything that I said was in there, if you cared to look.

Re: Study predicts imminent irreversible planetary collapse

#74

Earlier quoted context omitted.

Congratulations, you've stated the theory with far more specificity and a greater degree of testability than the paper's authors managed.

I'm just paraphrasing the paper. Everything that I said was in there, if you cared to look.

I've read it. The purpose of a scientific paper is to state its assumptions and suppositions clearly. The fact that this one doesn't even manage that is a big knock against it, aside from the fact that the basic "theory" is fundamentally not falsifiable.

Re: Study predicts imminent irreversible planetary collapse

#75
post #71

Earlier quoted context omitted.

Those formulas are models. They describe the world and can predict it's behaviour, but can also break down under certain conditions. For example, what happens when I put 240V across a regular 20Ohm resistor? According to V=IR you get 12A running through it - but I doubt you'll get that for very long. By your argument, V=IR must then be a "model" and is useless, with no predictive power, etc, etc. In practice, the onl…

No, those formulas are exact, you are just using them incorrectly. You think V=IR describes a resistor, it does not. It describes electricity. So it's not surprising that when applied to a resistor it doesn't work. You are trying to model a resistor, but you are not including everything in your model, so it fails. Which is exactly what I'm warning about. > By your argument, V=IR must then be a "model" and is useless,…

>You thought that V=IR completely describes a physical resistor, when it does not.

V=IR is a mathematical model of a resistor, useful under most circumstances except pathological ones. Can the model be improved? In most cases yes, but then it loses some value due to complexity.

This is why there are scientists in Antarctica: they're testing the model, gathering new data to see how well the models hold up. But for some reason you're acting as if those poor scientists haven't realised this yet.

If you want to continue to argue the point feel free, but you're disagreeing with every scientist and engineer on the planet. Try looking at http://en.wikipedia.org/wiki/Mathematical_model - what do you see? Ooh - equations.

  "essentially, all models are wrong, but some are useful" -- George E. P. Box

Re: Study predicts imminent irreversible planetary collapse

#76
post #71

Earlier quoted context omitted.

No, those formulas are exact, you are just using them incorrectly. You think V=IR describes a resistor, it does not. It describes electricity. So it's not surprising that when applied to a resistor it doesn't work. You are trying to model a resistor, but you are not including everything in your model, so it fails. Which is exactly what I'm warning about. > By your argument, V=IR must then be a "model" and is useless,…

>You thought that V=IR completely describes a physical resistor, when it does not. V=IR is a mathematical model of a resistor, useful under most circumstances except pathological ones. Can the model be improved? In most cases yes, but then it loses some value due to complexity. This is why there are scientists in Antarctica: they're testing the model, gathering new data to see how well the models hold up. But for som…

> V=IR is a mathematical model of a resistor

It's the basis for a model of a resistor, but it's an exact equation of resistance. There is a difference.

> they're testing the model, gathering new data to see how well the models hold up.

No, they are not testing the model, they are trying to improve the model by recording what it did in the past.

To test the model you make a prediction of what it will do in the future, then wait and see if it happens the way your model shows. It can't be done for climate though since it would take decades. They do try to test it by giving it old data and seeing if it predicts current conditions - which is great, but does not help in predicting the future since the input will be different this time.

> you're acting as if those poor scientists haven't realised this yet.

They most definitely do realize how poor the results are (just see how many weasel words they put in the paper linked to this topic), they just have no better options.

> try looking at http://en.wikipedia.org/wiki/Mathematical_model - what do you see? Ooh - equations.

Do you really not understand the difference between a model and a fundamental equation? A model does not have perfect input, and a model may not include all things that can affect the output.

An physical law (an equation usually), is exact. It might not apply to real physical objects (like the ideal gas law), but that doesn't make the equation a model - the equation is correct for where it's used, it just doesn't cover everything.

Excellent quote BTW, but don't take from that that everything is a model. The real world is not a model - if I test something and it does something in the real world, I have real information. In a model I only have the information I put in it, and it's simply impossible for me to put in everything.

I found a great example for you: http://en.wikipedia.org/wiki/Castle_Bravo#Cause_of_high_yiel...

They made a model - but they missed something. Good thing they were able to test it, and see what they missed. But if you don't have the ability to test? (Like climate.) Then your model is useless.

A model is useful only if you can test it. The model will help you know what to test, the model will help you see if you understand the topic. But a model you can not test is useless.

(Just to repeat myself: I'm not arguing about models, I'm arguing about models that can't be tested.)

Re: Study predicts imminent irreversible planetary collapse

#77

Earlier quoted context omitted.

I'm just paraphrasing the paper. Everything that I said was in there, if you cared to look.

I've read it. The purpose of a scientific paper is to state its assumptions and suppositions clearly. The fact that this one doesn't even manage that is a big knock against it, aside from the fact that the basic "theory" is fundamentally not falsifiable.

It's really not that hard to work out. That you don't know what "collapse" means in the context of an ecosystem is not the fault of the paper.

It's like arguing that a CS paper doesn't define what "compiler" means; there is a basic level of literacy expected when reading scientific papers.

Re: Study predicts imminent irreversible planetary collapse

#78

Earlier quoted context omitted.

Last I checked, we haven't had a civil war in a while. If we had a decently sized "massive expansion of government" on, say, a planetary scale (for a planet-sized problem), wouldn't that therefore lead to less wars?

Since government is creating massive problems already, such as the global debt crisis, I really don't think all encompassing planetary government is a good idea at all. People seem to think nothing could ever go wrong with such a concept. But history tells another story about government. We've had some very bad totalitarian governments. I'd rather not trust any single organization that will never face any competition…

> I'd rather not trust any single organization that will never face any competition.

Neither would I. That would be silly.

Can you tell me what government is? In my experience, people who are afraid of governments becoming totalitarian cannot seem to grasp what the government itself is. Would you be an exception to this trend?

Re: Study predicts imminent irreversible planetary collapse

#79
post #76

Earlier quoted context omitted.

>You thought that V=IR completely describes a physical resistor, when it does not. V=IR is a mathematical model of a resistor, useful under most circumstances except pathological ones. Can the model be improved? In most cases yes, but then it loses some value due to complexity. This is why there are scientists in Antarctica: they're testing the model, gathering new data to see how well the models hold up. But for som…

> V=IR is a mathematical model of a resistor It's the basis for a model of a resistor, but it's an exact equation of resistance. There is a difference. > they're testing the model, gathering new data to see how well the models hold up. No, they are not testing the model, they are trying to improve the model by recording what it did in the past. To test the model you make a prediction of what it will do in the future,…

Here, go and have a read of this article: http://skepticalscience.com/how-do-climate-models-work.html - they talk in great detail about how the models work, starting with one equation.

Also look at this image further down the page: http://www.skepticalscience.com/pics/sea_ice_prediction.jpg

The glacier model is wrong, but wrong in the wrong direction (Actually I think that's combined results from multiple models, but anyway...). How do they know? Because there are climatologists out on the ice, or in satellites taking measurements-1. Testing the model - you know, all that stuff that is supposedly impossible to do.

1- there are even high resolution GPS modules in Greenland which can estimate ice loss by how far up the crust lifts (as well as detecting plate tectonics).

Re: Study predicts imminent irreversible planetary collapse

#80
post #29

Earlier quoted context omitted.

Why stop there then? If you've decided that 'safe' indicates the continuation of the mass that comprises our planet, and not the particular, temporarily-compatible, form it takes today, then why even worry about the expansion of the sun? Or a collision which may shatter it? In how many ways is an asteroid cloud meaningfully less 'safe' than a single barren rock of comparable mass? I mean, you've already dispensed wit…

It's sarcasm. (viz. George Carlin, http://www.youtube.com/watch?v=eGOBm2J4tn0 at about 2:20 in; the whole thing is classic Carlin at his most abrasive.)

I'm a big fan of George Carlin, but that point was still irrelevant and largely self-defeating when he first popularized it.

For such an astute student of language, with an eye toward practicality over formality, I don't know how he could see a difference between his complaint that the colloquial 'save the planet' implied rather than explicitly expressed a human point of reference and his many rants against unnecessarily precise techno-jargon. (see: PTSD, pre-boarding, etc)

The only useful value in highlighting that 'save the planet' implies 'so we can still live here', is to draw attention to how the knee-jerk response to such slogans and policy suggestions [1] is the height of arrogance/ignorance.

But rather than exposing the absurdity of that knee-jerk response, his little rant has served as ammunition for that response, shifting the expectation of evidence of lasting harm to an intellectual game of pointless abstraction. [2]

As such it started, and continues, to bother me.

So, again, if you find any legitimate comfort in the idea of the planet continuing on without us (As Carlin may well have) there's no good reason to stop at that level of abstraction.

And if you just want to complain about colloquial language, generally speaking, that pursuit winds up on the receiving end of the bulk of Carlin's analysis of language.

[1] In short: dismissing any potential for a legitimate concern about defending life as we know it by casting conservationist policies as the work of extremists or dismissing any potential for damage by humans by suggesting that we're powerless to truly harm nature.

[2] E.g. "We may turn America's breadbasket into a dust bowl - but after we all starve to death, things will grow again!" As if that matters to the conservationist or their opponent, being as they would both have starved to death.

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