Wednesday, August 12, 2009

Andrei Why not use sheep guts to predict the future - it would be just as meaningful

Do you know what this pretty picture is? Any ideas?

Well this picture is the "science" that says that if we don't cut emissions the average temperature will rise by 2 degrees by 2100.


This is where the magic 2 degrees Celsius that has been bandied about in recent days has come from.

And what produced this pretty picture do you suppose? Computer models, which all agree that the temperature will rise.

Now the equations that govern the earths climate system are very very hard. Of the very small fraction that have even been formulated none have analytic solutions but have to be solved numerically.

In addition they exhibit a behavior called "initial condition instability". What this means is that a minute change in any one parameter will lead to a vastly different outcome as the system develops.

This is not a concept readily reduced to a soundbite but the closest I can come is it says Nobody can predict the future with any certainty.

You could with equal validity produce any number of models and run them with any number of initial conditions - some will predict warming, others cooling. Since warming is required for political purposes, political natural selection will eliminate any that do not produce the required estimates of warming.

This is picture is not science my friends - it is voodoo, meaningless dribble to be used for double talking politicians and agitators to grasp further control over the population by limiting their access to resources.

Nobody knows what the future may bring and anybody who claims they do is a charlatan, especially when they put numbers on things such as what the average global temperature will be at some future date.

But I am pissing in the wind here, the "science" has been decided, except it is not science its more akin to necromancy.


11 comment(s):

theatavism said...

Nobody can predict the future with any certainty.

I predict that on average this summer will be warmer than this winter.

Nobody knows what the future may bring and anybody who claims they do is a charlatan, especially when they put numbers on things such as what the average global temperature will be at some future date

Actually, the science isn't giving a hard number on the future average temperature (which will be influenced by weather which is chaotic, so very hard to predict) just probability densities. People aren't very good at dealing with probability and risk so the media usually reports it as a this or that number.

More importantly, what do suggest we do. Say "who knows, there is a slight chance pumping greenhouse gases into atmosphere will have some knock-on effect that counteracts there warming effect so let's do nothing"?

KG said...

"Say "who knows, there is a slight chance pumping greenhouse gases into atmosphere will have some knock-on effect that counteracts there warming effect so let's do nothing"?

Sounds like a lot more intelligent approach than the current warming hysteria....

Andrei said...

I predict that on average this summer will be warmer than this winter.

Yes and there is a finite probability you would be wrong

for example the famous poverty year 1816 - the year without a summer. A result of it is believed the eruption of Mt Tambora and weak solar activity - both unpredicted and unpredictable.

Actually, the science isn't giving a hard number on the future average temperature (which will be influenced by weather which is chaotic, so very hard to predict) just probability densities. People aren't very good at dealing with probability and risk so the media usually reports it as a this or that number.

The climate like the weather is chaotic and to use probability densities you need to be able to estimate them, the robustness of the estimate being entirely dependent upon the past behavior of the system and the accuracy to which can measure this past behavior.

Say "who knows, there is a slight chance pumping greenhouse gases into atmosphere will have some knock-on effect that counteracts there warming effect so let's do nothing"? Actually nobody "knows" the long term consequence of any complex human activity.

It is an assumption that CO2 emissions are going to lead to a warmer world based ultimately upon the specific heat of gaseous CO2.

This assumption for the most part ignores all the other factors which will influence this which are all interdependant and interact in ways far beyond our comprehension.

Finally it is an assumption that a warmer world would be a bad thing for mankind.

In reality the climate has changed continually throughout the history of mankind - sometimes for the better, sometimes for the worse. Lands that were productive cease to be and while lands that were marginal become lush.

And regardless of how the climate develops over the next century, millenium, eon this will be so until life itself becomes extinct.

Even that graph which I posted and is now eight years old looks silly when compared to how the climate has behaved in the interim and I predict it will look even sillier as the years go by.

theatavism said...

Yes and there is a finite probability you would be wrong

Once in 200 years. Seems like you can do a pretty accurate job of predicting climate.

The climate like the weather is chaotic

Evidence please?

This assumption for the most part ignores all the other factors which will influence this which are all interdependant and interact in ways far beyond our comprehension.

Yes, it's complex but I don't think we should do nothing because there is some slim chance that those uncertainties will balance out the known effects.

Andrei said...

Once in 200 years. Seems like you can do a pretty accurate job of predicting climate.

I do believe that the eruption of Mt Pinatubo in 1991 had a significant and measurable impact on the climate.

The climate like the weather is chaotic

Evidence please?


El Niño / La Niña

Yes, it's complex but I don't think we should do nothing because there is some slim chance that those uncertainties will balance out the known effects.

Incorrect the uncertainties overwhelm the "known effects" and when this happens as the future becomes UNPREDICTABLE

theatavism said...

El Niño / La Niña

Perhaps, but to they have to do with trends over multiple decades?

incorrect the uncertainties overwhelm the "known effects"

How do you know. In fact, how can you know?

Andrei said...

El Niño / La Niña

Perhaps, but to they have to do with trends over multiple decades?


Well I could just have easily used the Pacific decadal oscillation which has a timescale of decades

Or

the flip between Glacial and Interglacials with its timescales of 10s of thousands of years to 100s of thousands of years. All climate phenomena exhibiting chaotic behavior.

Which in itself should answer your second query but if it doesn't
consider the most important greenhouse gas - which would be water vapor and which of course is not evenly distributed globally, in height or even in time at a particular point within the atmosphere.

What effect does increasing/decreasing warmth have on Atmospheric water vapor and the consequences for

(2) Cloud formation
(3) Annual Snowfall in the Andes
(4) Number of Frosty nights
in central Otago

etc etc

ZenTiger said...

We could go off past predictions to measure accuracy. Remember the ice age that was predicted around 1970 that was going to hit us by the year 2000?

We can probably agree that that prediction was really bad on so many levels.

So how accurate is this data looking 9 years later? Is it spot on Avatism?

theatavism said...

Zen, are you really tying two of most pathetic denialist canards in one comment here?

There was no IPCC, no modelling and no scientific consensus on global cooling in the 1970s. As far a I know there was a single scientific paper that attempted to quantify the effects of pollution in the atmosphere by comparing the greenhouse heating with the dissipation of heat caused by aerosols scattering light. In that paper they decided the scattering would win out and a cooling trend would set in (but, of course, they were explicit in stating this depended on a value for the forcing of carbon that we know to be several times too small). Compare that with the support for global warming today ...


So how accurate is this data looking 9 years later?


If this is meant suggest that global warming has stopped since 2000 (1998?) then I really do despair.

If you'd like to see global temperatures plotted against IPCC projections look here [pdf] (though fitting curves in the way i think that paper does places undue weight on recent data-points)

Andrei,

I'm not sure that those things can properly called chaotic, but even if we grant that they are the question we need to ask with projections is do climate forcings behave in a more or less predictable way? The answers seems to be yes. More sun, more heat. More GHG, more heat. Of course other factors mean we can't predict the specific temperature at any time point, but that's beside the point (FWIW, clouds are in the IPCC models, though probably not accurately delt with. I don't know of any good reason to believe the net effect of clouds will save us)

I think I've tried this one on you before but think about a die. If I asked you to predict the outcome of a single roll you'd have no better than a 1/6 chance - the physics describing the roll are just too hard. But if I asked to predict the average value after 100 rolls you could calculate that it would be 3.5, and even know the standard deviation. With that knowledge you could even test whether I was playing with loaded dice...

ZenTiger said...

I asked "How accurate is this data looking 9 years later?"

You said: If this is meant suggest that global warming has stopped since 2000 (1998?) then I really do despair.

No, it wasn't meant to suggest anything. It was a question.


Zen, are you really tying two of most pathetic denialist canards in one comment here?

Almost, but not quite. Even if the future proves that we undergo global warming (note I did not say "man-made global warming") and sea level rises, I am suggesting that the government response to these scientific papers will prove to be as much as a "canard" as the impending ice age we faced in 1970.

Andrei said...

If this is meant suggest that global warming has stopped since 2000 (1998?) then I really do despair.

"GLOBAL WARMING" is a slogan designed to scare people into complying with whatever the user of the phrase is selling as the "solution". It is often combined with the word "DENIALIST" to describe those who see the proposed solution as snake oil at best.

The correct term is CLIMATE CHANGE which nobody denies and most assuredly has not stopped since 1990 or 2000 because it is a feature of the planet we inhabit not a bug nor in any way a new factor of human existence but one of the things we have to cope with.

I think I've tried this one on you before but think about a die. If I asked you to predict the outcome of a single roll you'd have no better than a 1/6 chance - the physics describing the roll are just too hard. But if I asked to predict the average value after 100 rolls you could calculate that it would be 3.5, and even know the standard deviation.

None of which would be useful in determining the result from the next throw which would be an integer in the range of 1-6 and most certainly not 3.5 (the average).

Now it is a common observation that life in the warmer latitudes is indeed both more abundant and diverse than in the higher and colder latitudes.

And of course the polar regions are to all intents and purposes uninhabitable, the poles being uninhabited entirely.

Given this why the assumption that the possibility of a warmer world is a scary prospect?

The future is unknown, nobody can control the weather or climate and given mankind's propensity for evil would you be comfortable if they could.

Who would you trust to set the planets thermostat even if it were possible?

Post a Comment

Please be respectful. Foul language and personal attacks may get your comment deleted without warning. Contact us if your comment doesn't appear - the spam filter may have grabbed it.