APOD: Global Warming Predictions (2009 April 21)

[gpobserver]

Chris Peterson wrote:

"Just trying to be brief. Basically, there's no point in discussing the matter further, since you've demonstrated a lack of understanding of the entire climate change issue, and of science itself. You base your arguments on largely non-technical sources (blogs, politicized websites, etc), and this latest attempt demonstrates only that you have no idea whatsoever how computer models work, or why they are valuable.

There are plenty of alarmist, pseudoscientific blogs and websites for people who think the way you do. I don't see the point or value of your wasting your time on a science oriented site like this one."

Thank you, Mr. Peterson. You have clearly illustrated what is so wrong with this debate. I have endeavored numerous times to engage in a debate of factual shortcomings and inconsistencies of the AGW hypothesis as well as introduce alternative,viable explanations of climate behavior. You and others have repeatedly declined to address these factual challenges and have resorted to ad hominem attacks, patronizing pontification, and calls to authority upon a non-existent 'consensus'. Now that you have shown your true colors and lack of genuine qualifications, I have no further desire to subject myself to your personal abuse. I will take delight at your continuned frustration in your quixotic efforts to 'save the planet' when that planet really doesn't need to be saved from CO2.

Best regards,
- Roy Tucker

PS - Gee, what a pity, too. We haven't even gotten to the stuff about isotopic signatures of atmospheric CO2 or inter-hemispheric gas exchange.

[gpobserver]

"Changes In The Sun Are Not Causing Global Warming, New Study Shows

http://www.sciencedaily.com/releases/20 ... 122425.htm"

Oh, joy! Another computer model. Whatever happened to collecting observations and actual experimentation?

http://www.mps.mpg.de/dokumente/publika ... i/c153.pdf

http://adsabs.harvard.edu/full/2001IAUS..203..602P

http://physicaplus.org.il/zope/home/en/ ... 511992_en/

[Chris Peterson]

Oh, joy! Another computer model. Whatever happened to collecting observations and actual experimentation?

Sure, lets build a time machine, so we can collect some actual data. And while we're at it, lets systematically adjust the Sun's output a bit either way, and record what happens over a century or so.

Computer models are nothing more than systems of scientific theories. They are based on observation, and are themselves, in fact, actual experiments. They are used when the process of evaluating the theories for actual output is too complex. Without computer models, we wouldn't be able to engage in exploration of the outer Solar System (they are the only way of determining the position of planets and moons to a high precision), the ability to predict weather over a span of a few weeks would be very limited (and jokes about weathermen aside, such predictions are actually quite good and of huge economic benefit), we wouldn't be able to analyze how proteins fold, or how galaxies evolve. We wouldn't be able to train pilots on simulators, or economically design safe cars. When you calculate how long it will take for a ball to drop a certain distance, you're applying a model. If you use your calculator, you're using a computer model.

[Dr. Skeptic]

"Changes In The Sun Are Not Causing Global Warming, New Study Shows

http://www.sciencedaily.com/releases/20 ... 122425.htm"

Oh, joy! Another computer model. Whatever happened to collecting observations and actual experimentation?

http://www.mps.mpg.de/dokumente/publika ... i/c153.pdf

http://adsabs.harvard.edu/full/2001IAUS..203..602P

http://physicaplus.org.il/zope/home/en/ ... 511992_en/

Computer models are far safer tools than leading an untethered experiment driven by big business on the one working biosphere we have - seeing how far the environment can be push before the casualties cut into profits.

Of the two unprovable opinions on AGW, I would prefer to error on the side of caution.
Also, global warming isn't the only concern with unrestrained use of fossil fuels, other documented related concerns number in the thousands.

Go ahead, deny there is concrete below.

[rstevenson]

A test subject jumps off the top of the Sears Tower and makes copious measurements on his descent.
- 0 sec s = 0 m/sec
- 5 sec s = 41 m/sec
- 10 sec s = 49 m/sec
- 15 sec s = 53 m/sec
- 20 sec s = 53 m/sec
- 24 sec maintaining terminal v, turbulents negligible, all is well.

53 m/sec air flow around the human body is uncomfortable but survivable, proving within the chosen parameters for the experiment, a fall from the Sears Tower is a survivable act.

Deceleration forces applied to human tissue and elasticity properties of concrete does not fall into the parameters of this study. Those and/or other issues will be addressed as needed when needed.

Some years ago my wife and I -- and a few thousand others -- saw a member of a parachute team fall to earth during a display here in Halifax, Nova Scotia -- and survive. He kept his wits about him when he realized his chute was not going to unwind, putting himself into a slow horizontal spiral, arms and legs well spread. There were suggestions he reached a terminal velocity of about 90 MPH, about 20% slower than your 50.3 m/sec, perhaps due to the drag of his unopened trailing chute. He bounced off a roof top onto the cinder driveway below, embedding his elbows and knees into the driveway. He was taken to hospital conscious but battered and broken. I recall he jumped again a year or so later.

I think a jump from the Sears Tower onto cement would not have such a happy ending, but await further data before committing one way or the other.

Rob

[StACase]

... Computer models ... are themselves, in fact, actual experiments...

Ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha!

[Dr. Skeptic]

... Computer models ... are themselves, in fact, actual experiments...

Ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha!

Didn't Einstein master "Thought Experiments"? Same thing without the paper.

[Chris Peterson]

Didn't Einstein master "Thought Experiments"? Same thing without the paper.

I wouldn't consider a thought experiment and a computer simulation quite the same thing. A thought experiment (in the usual sense) is more of a rationalization tool- something you use to direct your analysis of a problem. A computer simulation is experimental science in the truest sense. The simulation is nothing more than a numerical solution of a physical system (this is done all the time, from the trivial, like calculating the speed of a falling body, to the complex, like calculating the position of a planet, to the extremely complex, like solving for weather and climate states). The results of the calculation are then compared to observations. That's science at its most basic.

[StACase]

A computer simulation is experimental science in the truest sense. The simulation is nothing more than a numerical solution of a physical system (this is done all the time, from the trivial, like calculating the speed of a falling body, to the complex, like calculating the position of a planet, to the extremely complex, like solving for weather and climate states). The results of the calculation are then compared to observations. That's science at its most basic.

Wow! Talk about White is Black, Black is White, Cart before the Horse thinking! The observations are the experiment, the computer work is the thesis. And to my point, there are 20 or so different computer models in the IPCC AR4, see my post above, and for 2008 they were ALL wrong! Every one of them projected i.e., theorized, that is to say stated a thesis, that average world temperatures would be higher, they weren't. It follows that if they are all wrong a mere 8 years into a 100-year projection, why should anyone believe they will be right 92 years from now?

If you can't hit the broad side of a barn at 25 feet, you aren't going to hit the target at 100 meters.

[Dr. Skeptic]

A computer simulation is experimental science in the truest sense. The simulation is nothing more than a numerical solution of a physical system (this is done all the time, from the trivial, like calculating the speed of a falling body, to the complex, like calculating the position of a planet, to the extremely complex, like solving for weather and climate states). The results of the calculation are then compared to observations. That's science at its most basic.

Wow! Talk about White is Black, Black is White, Cart before the Horse thinking! The observations are the experiment, the computer work is the thesis. And to my point, there are 20 or so different computer models in the IPCC AR4, see my post above, and for 2008 they were ALL wrong! Every one of them projected i.e., theorized, that is to say stated a thesis, that average world temperatures would be higher, they weren't. It follows that if they are all wrong a mere 8 years into a 100-year projection, why should anyone believe they will be right 92 years from now?

If you can't hit the broad side of a barn at 25 feet, you aren't going to hit the target at 100 meters.

So the mode/data against AGW IS "hitting the barn" at 25 feet?

PS: A computer model is empirical data inserted into a thought experiment, or, the thought experiment is the designing stage of the computer model. Either way, "thought testing" in theory developement and "data testing" in a computer model are both valid experimentation (testing) techniques.

[Chris Peterson]

Wow! Talk about White is Black, Black is White, Cart before the Horse thinking! The observations are the experiment, the computer work is the thesis.

I'd say the model is the theory (really, a set of interacting theories), the output of the model (the simulation) is the experiment, and this is compared against the observations, historical, proxied, or current. How is that different from any other science? For instance, other than the complexity of the model, how is this functionally different from modeling the future position of planets? Not long ago people used a fairly complex model called VSOP82 to do this. Then the ability to do astrometry got better, and the output of VSOP82 was compared against actual planetary position measurements. Because errors became measureable, the model was made more complex, resulting in VSOP87, which is what we usually use now to get precise positions. And people are still looking at refinements of the model, adding more terms, dealing with more complex interactions.

And to my point, there are 20 or so different computer models in the IPCC AR4, see my post above, and for 2008 they were ALL wrong! Every one of them projected i.e., theorized, that is to say stated a thesis, that average world temperatures would be higher, they weren't. It follows that if they are all wrong a mere 8 years into a 100-year projection, why should anyone believe they will be right 92 years from now?

They weren't "wrong" at all. Climate and weather are both modeled statistically. The model predictions for a single year are specified with very low confidence- barely better than 50-50. Nobody would consider evaluating or modifying a model based on a single year of data. Saying the model is "wrong" is like saying basic statistics is wrong because you managed to toss three heads in a row.

The confidence levels on the models only starts to become fair when you look at decadal averages. In some cases, longer than that. To evaluate the results over any short period of a few years or less makes no sense.

If you look at what the models actually output, which is decadal averages, the trend is still upwards, and most of the recent years are still amongst the hottest on record. So even in the short term, it isn't obvious how the models are "wrong".

[harry]

G'day from the land of ozzzzzzzzzz

Chris I fully agree with you in what you say.

The model shold be taken from long term readings and fossil evidence.
These models exist.

The Earth is doing its thing. Its perfect. You got to be lucky sometimes.

Try living anywhere else.

If you like acid and heat try Venus.

If you like the cold and no Oxygen try Mars.

[StACase]

The confidence levels on the models only starts to become fair when you look at decadal averages. In some cases, longer than that. To evaluate the results over any short period of a few years or less makes no sense.

Isn't that ever convenient. We all have to wait ten years to find out if there's anything to it. Meanwhile you damn people set about jamming cap & trade and God knows what down our throats. I'm 64 and I don't have the time to wait around to drive a stake through the heart of this fraudulent beast.

Besides, I look at those figures I referenced in the IPCC's AR4 and as any fool can see when compared to the actual record, THEY ARE WRONG!

[Chris Peterson]

Isn't that ever convenient. We all have to wait ten years to find out if there's anything to it. Meanwhile you damn people set about jamming cap & trade and God knows what down our throats. I'm 64 and I don't have the time to wait around to drive a stake through the heart of this fraudulent beast.

Besides, I look at those figures I referenced in the IPCC's AR4 and as any fool can see when compared to the actual record, THEY ARE WRONG!

As noted, an incorrect prediction for the short term doesn't make the model wrong. Your daily weather forecast comes from a similar model, and sometimes it's right and sometimes wrong. In the long run, it's right more often than not, so it has value. With a chaotic system (which includes both weather and climate) the best you can ever do is provide an answer with some statistical merit. And in the case of climate, that means that you have to look at many years. It has nothing to do with "convenient" or otherwise. All you have to do is look at the temperature record for the last century, which is quite good, and you can see just how noisy the annualized data is. The upward trend is obvious and significant over that period, but you can pick arbitrary ten-year intervals that show an average that increases (1999-2009), decreases (1940-1950), or stays the same (1970-1980). That's actual data, nothing from a simulation. It should be obvious that given that sort of variability, you can't expect any model to reliably predict trends over just a few years.

FWIW, I'm not in a position to set policy like caps & trades, and those who are didn't ask my opinion.

[Czerno]

I'm a layman here, but I too am a bit skeptical of the predictive power of physical/mathematical/computer models of the climate.

One question among a dozen, of which I'd like to read unprejudiced answers : how well understood is the global cycle of the (excess) CO² released in the atmosphere ? Since it is a heavier than air gas, gravity will tend to concentrate it a low atmospheric layer and be absorbed by vegetation on land, and dissolved in ocean waters. Isn't such a system going to limit CO² concentrations rather than let them increase without bound like the alamists tend to make believe ? Maybe there are long time constants associated with the processes I've mentionned, in any case what is sure is there is not so much fossil carbon remaining to be burnt so the system WILL stabilise at a point. Besides I find preoccupying that we are pushed towards measures against a limited (if any) "global warming" at the same time when, it is well known (Milankowich), we are heading towards a new glaciary age.

--
Czerno

The below paragraph is off-topic, feel free to ignore it.
(This said, I'm all in favour of the American - of all peole - reducing their ridiculously excessive waste of resources in general leading to an attitude more friendly to Nature and the people of this world. But I'm not sure this is what this is about, alas... As always the North American want the rest of the world to suffer for their little comfort. )

[Chris Peterson]

One question among a dozen, of which I'd like to read unprejudiced answers : how well understood is the global cycle of the (excess) CO² released in the atmosphere ?

That is probably among the best understood components of our climate system. The least well understood elements in the models are probably the water and water vapor feedback cycles associated mainly with clouds. This is a complex system that contains both positive and negative feedback components.

Since it is a heavier than air gas, gravity will tend to concentrate it a low atmospheric layer and be absorbed by vegetation on land, and dissolved in ocean waters.

No, this doesn't happen. There is no stratification of gases in the atmosphere below about 100 km, because the mixing rate is very high. Above 100 km there is little mixing, and gases start stratifying according to their molar mass.

[StACase]

The least well understood elements in the models are probably the water and water vapor feedback cycles associated mainly with clouds. This is a complex system that contains both positive and negative feedback components.

Doesn't seem to stop them from making 100 year predictions. Doesn't seem to stop you from defending them either.

[Chris Peterson]

The least well understood elements in the models are probably the water and water vapor feedback cycles associated mainly with clouds. This is a complex system that contains both positive and negative feedback components.

Doesn't seem to stop them from making 100 year predictions. Doesn't seem to stop you from defending them either.

What would you have them do, simply ignore something that is somewhat, but not perfectly understood? The models are good. They provide decent "predictions" of the past, meaning that they are at least capturing the major elements of climatic systems. The ramifications of the worse case change over the next century are completely devastating. So the models get built, the observations made, the models refined, and those responsible for making policy decisions do the best they can to find an optimal response. Sounds pretty rational to me.

[bystander]

No, since the models couldn't accurately predict a single year's temperatures, they are totally useless and should be scrapped. Obviously we should continue to pollute the atmosphere, rivers, lakes and oceans; continue to destroy the forests and wreck havoc on our environment; and generally render this habitat we call earth incapable of sustaining life; all in the holy name of profit.

What difference does it make that the models didn't predict the weather for one year. Indeed, what difference does it make that AGW is real or not. Reducing pollution, finding sustainable alternative forms of energy, and reducing our negative impact on our environment are all goals towards which we should be striving. As for the environmental models, they are worthy experiments, providing some understanding of the environment in which we live.

[Dr. Skeptic]

We have AGW computer models with reliabilities that aren't meeting "everyone" expectations, so, is there an statistical "reliability threshold" that will satisfy "everyone's expectations? Without a defining a greenhouse gas thresholds is stating the Earth will always be self correcting and no matter what humans do it will not adversely effect the global environment.

Innocent until proven guilty is a a hard sell with billions of lives at stake.

[StACase]

What would you have them do, simply ignore something that is somewhat, but not perfectly understood?

Point taken, the academics should continue as they always have.

The ramifications of the worse case change over the next century are completely devastating.

This is probably the number one biggest lie in the entire issue. We know that climate will change, history and geology tell us that it does. You and others are telling us that a warmer world will be "devastating"! Really? Longer growing seasons? More CO2 and more rain to increase agricultural yields? More higher latitude land available for agriculture? Less ice and snow? More fresh water? These things are devastating? Telling us that global warming will be devastating is The Big Lie.

So the models get built, the observations made, the models refined, and those responsible for making policy decisions do the best they can to find an optimal response.

The worst thing projected by "Global Warming" is sea level rise. An optimal response would be to plan for it.

If it were decided that we really have to reduce CO2 emissions, an optimal governmental solution to that would be regulation at the mines and wells. The cap and trade scheme merely shifts the point of fossil fuel combustion. If the United States doesn't burn the coal and oil, somebody else will. However, regulating production at the world's mines and wells will surely start a war. Well really, how do you propose we force China to stop producing coal?

Sounds pretty rational to me.

Most of what people on your side of the argument say sounds irrational to me, especially the solutions.

[StACase]

Innocent until proven guilty is a a hard sell with billions of lives at stake.

How many lives do you think would be at stake if we start wars over CO2 regluation?

[dolly004]

it is not our lives that will be at stake but the generations to come..
simulation rachat de credit

[Chris Peterson]

The ramifications of the worse case change over the next century are completely devastating.

This is probably the number one biggest lie in the entire issue. We know that climate will change, history and geology tell us that it does. You and others are telling us that a warmer world will be "devastating"!

What I said is that the worst case predictions are devastating. By that, I mean changes in sea level of a few meters, significant shifts in the location of food production zones, significant shifts in storm patterns, serious regional problems with droughts and floods. The economic effects of something like that would certainly cause multiple wars, and could easily collapse modern civilization. Yes, I'd call that devastating. It has happened to cultures in the past from smaller climate shifts. And while that is the worst case scenario, it is serious enough that I (and obviously, many others) think it would be foolish to not take it into consideration- even if there is only a few percent chance of it happening. You'd probably take your doctor's advice to undergo a mildly unpleasant course of treatment to avoid a several percent chance of dying.

My own view is that there is nothing to lose and everything to gain, since I see a plan to force us away from carbon-based energy sources as being very good for the economy. So the environment wins, and our economy wins.

If it were decided that we really have to reduce CO2 emissions, an optimal governmental solution to that would be regulation at the mines and wells. The cap and trade scheme merely shifts the point of fossil fuel combustion. If the United States doesn't burn the coal and oil, somebody else will. However, regulating production at the world's mines and wells will surely start a war. Well really, how do you propose we force China to stop producing coal?

I'd tax the heck out of everything that releases carbon during its production or use. That would suddenly make most of what is produced in China a lot more expensive in the U.S.

That said, I think the whole issue with China is misunderstood. The future of energy production is in renewable sources. China knows that, and is too smart to be left behind. Whoever controls the means of energy production controls the world. China has a very large renewable energy program already. And in the shorter term, you don't need to stop burning coal, you just need to capture the carbon. We already know how to do that, and the cost is a lot less than the actual cost of releasing the carbon. So as soon as you tax carbon to reflect its actual cost, capturing CO2 at the time you burn coal becomes a very economic strategy.

[Chris Peterson]

What would you have them do, simply ignore something that is somewhat, but not perfectly understood?

Point taken, the academics should continue as they always have.

And from the standpoint of this forum, that's really the correct answer. We're talking about science here, and the state of climate research is healthy. The quality of the research is high and the results are of great practical use, as well as theoretical interest. Like any new area of investigation, the results are incomplete, but improving all the time. That is exactly what we expect of scientific investigation.

The discussion of any policy based on those results is an entirely different matter, is not scientific, will engender as many opinions as there are participants, and doesn't really fit into the charter of this forum.