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Post by nautonnier on Aug 18, 2009 16:11:58 GMT
I see glc is still telling us about his irrelevant calculations. So is Richard Lindzen as he agrees with the 1 deg per CO2 doubling - and why not as nothing seems to stop your irrelevant ramblings about convection and latent heat. It still doesn't appear to have dawned on you that the only way the climate system loses heat is by radiation Yes the Earth loses heat by radiation from the TOA How the heat reaches the TOA is what we are talking about You will need to recalculate 'radiative forcing' as that is defined as the effect at the tropopause NOT the TOA Energy can reach the tropopause in many ways some of them more efficient than radiation. Albedo reduces the INPUT of radiation If you want to use solely radiation then you should only use the TOA and accept that the extent of the TOA alters.
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Post by jimcripwell on Aug 18, 2009 16:14:57 GMT
glc writes "It still doesn't appear to have dawned on you that the only way the climate system loses heat is by radiation"
Since I suspect that I am a older than you are, I am 84, I believe I have known that the only way that the earth loses heat is by radiation, for a longer time than you have. That is not, and never will be, the issue. The issue is, is the amount of heat that is lost by the earth through radiation affected by conduction, convection and the latent heat of water? All your calculations assume that these factors have no effect whatsoever, yet you offer no references, and not one single solitary jot of scientific evidence to support this assumption.
When I get a reference from you that shows that radiative transfer models, which solve real life problems, can estimate a correct value for radiative forcing for the doubling of CO2, (as defined by the IPCC in Chapter 6 of the TAR), which is a purely hypothetical situation, I may think there is some science behind your assertions.
However, the reference does not exist. I know it does not exist because if anyone tried to write it, their effort would show them to what the would be; charlatans.
And I could not care less what Richerd Lindzen believes. Nullius in verbia.
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Post by glc on Aug 18, 2009 18:46:14 GMT
Since I suspect that I am a older than you are, I am 84, I believe I have known that the only way that the earth loses heat is by radiation, for a longer time than you have. That is not, and never will be, the issue. The issue is, is the amount of heat that is lost by the earth through radiation affected by conduction, convection and the latent heat of water?
What do you mean "affected by conduction, convection and the latent heat of water"?
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Post by jimcripwell on Aug 18, 2009 19:24:17 GMT
glcwrites "What do you mean "affected by conduction, convection and the latent heat of water"? "
This is a very simplified explanation. At some point, some part of the atmosphere radiates heat directly into space. The amount of energy lost depends on the temperature of whatever is radiating. At the TOA, the heat flow to whatever is radiating, and therefore it's temperature, is governed by what is going on in the earth's atmosphere. As I understand what your calculations do, you assume that this heat flow, and therefore the radiating temperature, is governed solely by radiation. My concern is that this heat flow is affected very greatly by the effects of conduction, convection and the latent heat of water.
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Post by sentient on Aug 18, 2009 23:31:49 GMT
Just to re-focus the discussion just a tad, here is a recent press release from Rice University regarding models and their results with relevance to this discussion. As with all blogs, a little re-focus is good now and then....
7/14/2009
CONTACT: Jade Boyd PHONE: 713-348-6778 E-MAIL: jadeboyd@rice.edu
Global warming: Our best guess is likely wrong Unknown processes account for much of warming in ancient hot spell
No one knows exactly how much Earth's climate will warm due to carbon emissions, but a new study this week suggests scientists' best predictions about global warming might be incorrect.
The study, which appears in Nature Geoscience, found that climate models explain only about half of the heating that occurred during a well-documented period of rapid global warming in Earth's ancient past. The study, which was published online today, contains an analysis of published records from a period of rapid climatic warming about 55 million years ago known as the Palaeocene-Eocene thermal maximum, or PETM.
"In a nutshell, theoretical models cannot explain what we observe in the geological record," said oceanographer Gerald thingyens, a co-author of the study and professor of Earth science at Rice University. "There appears to be something fundamentally wrong with the way temperature and carbon are linked in climate models."
During the PETM, for reasons that are still unknown, the amount of carbon in Earth's atmosphere rose rapidly. For this reason, the PETM, which has been identified in hundreds of sediment core samples worldwide, is probably the best ancient climate analogue for present-day Earth.
In addition to rapidly rising levels of atmospheric carbon, global surface temperatures rose dramatically during the PETM. Average temperatures worldwide rose by about 7 degrees Celsius -- about 13 degrees Fahrenheit -- in the relatively short geological span of about 10,000 years.
Many of the findings come from studies of core samples drilled from the deep seafloor over the past two decades. When oceanographers study these samples, they can see changes in the carbon cycle during the PETM.
"You go along a core and everything's the same, the same, the same, and then suddenly you pass this time line and the carbon chemistry is completely different," thingyens said. "This has been documented time and again at sites all over the world."
Based on findings related to oceanic acidity levels during the PETM and on calculations about the cycling of carbon among the oceans, air, plants and soil, thingyens and co-authors Richard Zeebe of the University of Hawaii and James Zachos of the University of California-Santa Cruz determined that the level of carbon dioxide in the atmosphere increased by about 70 percent during the PETM.
That's significant because it does not represent a doubling of atmospheric carbon dioxide. Since the start of the industrial revolution, carbon dioxide levels are believed to have risen by about one-third, largely due to the burning of fossil fuels. If present rates of fossil-fuel consumption continue, the doubling of carbon dioxide from fossil fuels will occur sometime within the next century or two.
Doubling of atmospheric carbon dioxide is an oft-talked-about threshold, and today's climate models include accepted values for the climate's sensitivity to doubling. Using these accepted values and the PETM carbon data, the researchers found that the models could only explain about half of the warming that Earth experienced 55 million years ago.
The conclusion, thingyens said, is that something other than carbon dioxide caused much of the heating during the PETM. "Some feedback loop or other processes that aren't accounted for in these models -- the same ones used by the IPCC for current best estimates of 21st Century warming -- caused a substantial portion of the warming that occurred during the PETM."
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Post by sentient on Aug 19, 2009 0:22:38 GMT
Can someone give a newbie some help on posting relatively small (way less than 1,024kb) jpeg's?
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Post by poitsplace on Aug 19, 2009 3:25:40 GMT
Can someone give a newbie some help on posting relatively small (way less than 1,024kb) jpeg's? just find a place somewhere online that hosts images and put them there...then enter the URL in your message in the editor here, highlight it and click the 4th button on the second row in the tools (between the globe (web) and email buttons)
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Post by steve on Aug 19, 2009 11:36:53 GMT
I have been watching this board for some time and find it very useful in many ways. I practice in the fields of geology, sedimentology, hydrogeology and geophysics. For about the past 25 or so years, the field of paleoclimatology, which grew out of geology, has increasingly been a focus of study as the paleoclimate controlled (to a large extent) what type of sediment was being deposited and at what rate. It was the release of the first IPCC report that I became somewhat shocked at the use of models to predict future climate. Not so much at their use, but what has become almost their patent believability. Anyone who has really spent any time using models knows that you can often get what you want by grooming your data or any of the myriad assumptions in the model itself. For instance, I often use hydrogeologic models to model air flow in the subsurface, not water. I must trick the model, but I can get it to do what I want it to do. I often spend time testifying on the use and abuse of such models in environmental torts (contaminated sites). The modellers, who *really* have spent many years using models are well aware of the issues of climate models. They are also well aware of the successes that climate models have had in demonstrating and predicting real climate phenomena, not least the observed warming since the 1970s. Ignoring the fact that 68% of psychology statistics are made up, this is entirely the strategy of those who seek to undermine the consensus view that CO2 emissions are a real threat to existing societies. For the rest of the post: 1. Just because climate models cannot accurately reproduce past abrupt climate change does not mean that they are faulty. First, proxy evidence is limited. Secondly some past simulations take too long to run (earth system models typically only run 4-5 years per day on supercomputers). 2. Just because other things can cause climate change does not rule out or belittle the importance of the current increase in CO2 to the current climate. Nothing you've said (and I'll admit I've scan read, having come to this debate late) appears to address this including your "why models haven't got it right" article which simply states that our current modifications to the climate are likely to be *more* severe, not less than those envisaged by the climate projections which assume limited impact on other parts of the ecosystem.
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Post by radiant on Aug 19, 2009 11:56:02 GMT
The modellers, who *really* have spent many years using models are well aware of the issues of climate models. They are also well aware of the successes that climate models have had in demonstrating and predicting real climate phenomena, not least the observed warming since the 1970s. Why are you *really* correct when it could have just warmed up anyway? Stephen Schneider was predicting an ice age back in 1971 at a time when glaciers were advancing in north america and northern hemispheric sea ice was reaching the maximum of 1973 then by 1980 he was being critical of people who said it was definately going to be an ice age and now he is predicting the earth will warm If you put sufficient monkeys on the topic then one group will type the correct answer
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Post by sigurdur on Aug 19, 2009 13:17:58 GMT
I have been watching this board for some time and find it very useful in many ways. I practice in the fields of geology, sedimentology, hydrogeology and geophysics. For about the past 25 or so years, the field of paleoclimatology, which grew out of geology, has increasingly been a focus of study as the paleoclimate controlled (to a large extent) what type of sediment was being deposited and at what rate. It was the release of the first IPCC report that I became somewhat shocked at the use of models to predict future climate. Not so much at their use, but what has become almost their patent believability. Anyone who has really spent any time using models knows that you can often get what you want by grooming your data or any of the myriad assumptions in the model itself. For instance, I often use hydrogeologic models to model air flow in the subsurface, not water. I must trick the model, but I can get it to do what I want it to do. I often spend time testifying on the use and abuse of such models in environmental torts (contaminated sites). The modellers, who *really* have spent many years using models are well aware of the issues of climate models. They are also well aware of the successes that climate models have had in demonstrating and predicting real climate phenomena, not least the observed warming since the 1970s. Ignoring the fact that 68% of psychology statistics are made up, this is entirely the strategy of those who seek to undermine the consensus view that CO2 emissions are a real threat to existing societies. For the rest of the post: 1. Just because climate models cannot accurately reproduce past abrupt climate change does not mean that they are faulty. First, proxy evidence is limited. Secondly some past simulations take too long to run (earth system models typically only run 4-5 years per day on supercomputers). 2. Just because other things can cause climate change does not rule out or belittle the importance of the current increase in CO2 to the current climate. Nothing you've said (and I'll admit I've scan read, having come to this debate late) appears to address this including your "why models haven't got it right" article which simply states that our current modifications to the climate are likely to be *more* severe, not less than those envisaged by the climate projections which assume limited impact on other parts of the ecosystem. I am laughing now. Good one, the models predicted the warmth since the 70's. Gosh, I PREDICTED the warmth since the 70's and my only model runs in my head.
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Post by steve on Aug 19, 2009 14:28:38 GMT
You've read the meaning of two or three words of the sentence but missed the context. Still insubstantive, unconstructive replies are a quite effective way of avoiding the issue, so I'm not surprised by your tactics.
Scientists that use models base their trust in the model on the fact that they have demonstrated climate phenomena that have not previously been observed *including* warming since the 1970s.
When you have presented your monkey-authored play to the West End, *then* I'll take your point seriously.
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Post by nautonnier on Aug 19, 2009 14:49:20 GMT
You've read the meaning of two or three words of the sentence but missed the context. Still insubstantive, unconstructive replies are a quite effective way of avoiding the issue, so I'm not surprised by your tactics. Scientists that use models base their trust in the model on the fact that they have demonstrated climate phenomena that have not previously been observed *including* warming since the 1970s. When you have presented your monkey-authored play to the West End, *then* I'll take your point seriously. I find scientists' trust in models varies inversely with the likelihood of validation. This is why climate scientists totally believe the output of their models and weather forecasters tend to hedge their bets. Engineers building things that can kill people if things go wrong tend not to trust their models unless there is a LOT of baselining and validation. Even then extremely sophisticated models of simple systems often fail - for example the failure of the Airbus A380 wing in stress testing. Then before operational use there are years of test flights validating the modeled behavior. Trust in this case is a variable dependent on the use to which the model is put. So Steve - you can continue trusting the models where one of the couple of dozen in the spaghetti occasionally matches some event and all you suffer is some minor embarrassment if you choose the wrong one. But just think how much trust you would put in a GCM model if your life depended on it being totally correct. Due to past experience - I am used to models in the second category - so I feel that current GCMs are assumption driven toys used for political argument and should not be 'trusted'.
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Post by radiant on Aug 19, 2009 19:18:41 GMT
You've read the meaning of two or three words of the sentence but missed the context. Still insubstantive, unconstructive replies are a quite effective way of avoiding the issue, so I'm not surprised by your tactics. Scientists that use models base their trust in the model on the fact that they have demonstrated climate phenomena that have not previously been observed *including* warming since the 1970s. When you have presented your monkey-authored play to the West End, *then* I'll take your point seriously. Here we go again. More claims i am a criminal who twists things to suit some agenda while you alone know the truth. Evidently you cannot grasp the real possibility the earth just warms and cools occasionally and nothing meaningful at all was predicted. Consequentially you twist what i say to imply i am inventing things to avoid the truth you present Once again you show your contempt for people who dont believe what you believe and assume you are the guardian of truth. You just made the wild claim that models predicted something in the 1970's that could have happened anyway due to science you dont understand and when i pointed that out to you then you accuse me of making unsubstantiated claims. And i note elsewhere that you accuse me of being overly emotional. All i have done is observe that correctly forcasting a trend that would have happened anyway proves absolutely nothing. Stephen Schneider observed build up of ice for 20 years and forcast a little ice age possibility. When the ice did not build further after 1973 that possibility became less likely and we can assume at that point it was warming when melting was observed after some years. No rocket science models were required. Climate varies. The earth warms and cools. It appears it is warming since around 1850 and cools and warms in that trend at the moment. The 1920's to 1940's are a known warming period with rapid sea ice melting with high temps observed in the 1930's particularly. Sea ice then built up from the 50's to 1973. All of this was observed by Schnieder and others.
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Post by nonentropic on Aug 19, 2009 20:54:52 GMT
To run a model on a supper computer would take 1 day per 4 or 5 years and the only backward prediction that has been done is the 70's to now. These folk have big budgets, it sounds like the results were of mark. In addition would it not have been spectacular if the model had shown that the world temps would run flat at most in the last 10 years to have predicted this at turn of the century. That would have convinced me. So to recap the model works well in predicting the 70's to the late 90's and it to expensive to run the model further back, but we should be happy to adjust the fiscal relationship of the world to the tune of several trillion dollars on the basis of this. The ice is get thin but not where they think.
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Post by sentient on Aug 21, 2009 1:29:36 GMT
Obviously a lot of acrimony here, like most places where climate is discussed. I would like to attempt to refocus the discussion once again, but this time with a slight twist. What I am most interested in is not whether or not one believes in AGW or not, but the psychology behind the personal decision to tilt one way or the other. This is hard for each of us to even think about. Essentially it boils down to just this. Those of us that have chosen to believe in the model results, why? Those of us that do not believe in the models or their results, why?
Not so much the data, but why you believe one way or the other. Try to think back to when you first became interested in this subject. Harken back to the moment when you first tilted one way or the other, and what motivated you to do so.
No one can prove or accurately predict the future, but what I was trying to get at with this thread is why the models moved you, or why they did not.
For example, I switched sides, yes, more or less. Being wholly immersed in environmental cleanups most of my career, I have seen some really awesome environmental devastation, aquifers ruined, habitats contaminated beyond belief, so it wasn't a hard leap for me to respond to the CO2 thing at first. Two things were responsible for "turning me". The predictions of temperature and sea level rises were so small compared to natural transitions, that I quickly realized that this was a signal to noise problem in the natural world. Here in the LA Basin, we drill into the Holocene sediments of the Bellflower and Ballona aquitards regularly, it is here where most of the "leaks" are hosted as they are carbon-rich, mostly fine-grained sediments typical of a more or less staid climate characterized by long periods of drought punctuated by ENSO style events where we can get an entire year's worth of precipitation in a single storm event. The carbon rich, dark clays and silts sucking in and locking up fuels, solvents and metals in precisely the same way we use activated carbon to to adsorb it out of the groundwater. The LA, San Gabriel and Santa Ana rivers are relatively short, and before we poured concrete channels to contain them, such storm events raised havoc throughout the basin causing these desert rivers, which never carry enough water to carve a stable channel normally, and mostly flowed in the channel sands deposited from the last major storm session below the surface. But when these cycles came, the LA Basin was literally "flushed" just like a toilet, the "rivers" rapidly clogging their more or less non-existent channels, whipping around the basin, depositing fine silts and muds across the flooded basin, then when the storms ceased and the flows diminished, cutting a nascent channel eventually the flows too low to flow above the sands and reverting back to underflow to await the next time the flows overpowered the minimal channels once again.
Drill through them and almost instantly you reach the thick channels and widespread beach deposits characteristic of the last major climate change, Termination I, when sea levels rose rapidly ~400 feet in what simply had to be just thousands of years of incredibly high flows carrying massive amounts of sediments from the surrounding high mountains which rim this watershed.
Chase major contamination deeper, into the lower aquifers and aquitards, and the pattern repeats time and time again. Interglacials and ice ages stacked up and forming our drinking water aquifers with each ice age swing into interglacial, and the aquitards recording the slower and lower flows capable of carrying only the silts, clays and fine sands similar to the Bellflower/Ballona aquitards which separate our aquifers.
This just didn't gel with a 2-foot (AR4 maximum) or 20-foot (Al Gore) rise in sea levels. Something more ominous was afoot. For me it was a case of who was kidding who here? Me, a geologist who has cored this record dozens of times should be traumatized by predictions that literally don't come close to measuring up to this much natural noise? That just didn't compute. So I got onto the internet and the regional libraries and searched out everything I could relating to the research documenting the Quaternary record.
Now I was scared. It all came home to roost for me. It wasn't that CO2 couldn't cause a climate change event, we really have no idea. It was the fact that for literally hundreds of documented abrupt climate changes in the Quaternary, it never did. The ice core records from both poles, the ostracod oxygen isotope studies during the intervals of the cores and extending far beyond those records into the recent (geologic mind you) past painted a far different picture of reliable, dramatic, abrupt and seemingly unavoidable climate changes which made the current argument something akin to two fleas arguing over who owns the dog they are riding on.
So it is this I am looking for. What made up your mind for you? I found I could not deny the awesome records I had held in my hands for decades, and the understanding I gained from delving deeper into the 20th century knowledge base made denial of the proven specter of natural climate change a virtual impossibility for me.
What makes either side an impossibility for you? Tell us why, and please do not descend into acrimony. Here we may test the psychology of climate change.
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