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I have read an interesting blog by Jim Manzi who points out some interesting editing by those responsible for the 4AR WG1 report. The original draft stated in Chapter 8 (Climate Models and Their Evaluation: quote: Question 8.1: “As a consequence, models continue to display a substantial range of global temperature change in response to specified greenhouse gas forcing (refer Chapter 10), To date it has not been possible to quantify how errors in a model’s simulation of specific climate observations impact on errors in its future climate projections, but a few studies suggest this may be possible in the future. Despite such uncertainties,…”
In the final version: quote: “Consequently, models continue to display a substantial range of global temperature change in response to specified greenhouse gas forcing (see Chapter 10). Despite such uncertainties,…”
So why was the following removed? quote: “it has not been possible to quantify how errors in a model’s simulation of specific climate observations impact on errors in its future climate projections.”
JL has a very reasonable point. If we don't know what the error bars are or whether they are actually possible to apply, that undermines the basis of using the modelling scenarios as applied by the IPCC report. |
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CO2 has gone up from 280ppm to over 380ppm primarily due to fossil fuel emissions - about 30% increase. You are looking at the wrong websites.
Methane has also gone up, but the concentration of methane is much smaller than CO2, so the fact that per molecule it is a stronger greenhouse gas is balanced by its lower concentration.
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quote: JL has a very reasonable point. If we don't know what the error bars are or whether they are actually possible to apply, that undermines the basis of using the modelling scenarios as applied by the IPCC report.
Firstly, trying to pick on an edit to a draft document seems a bit silly to me. When I write documents I probably delete more text than is in the final version! The sentence seemed to say, we can see what the errors in the simulation are now, but don't know how the same errors would manifest in another scenario - which doesn't say a lot really. Certainly, such a statement needs to be expanded on if it is to say. But the sentence doesn't say "we don't know what the errors are". |
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quote: Originally posted by Steve_M: quote: JL has a very reasonable point. If we don't know what the error bars are or whether they are actually possible to apply, that undermines the basis of using the modelling scenarios as applied by the IPCC report.
Firstly, trying to pick on an edit to a draft document seems a bit silly to me. When I write documents I probably delete more text than is in the final version! The sentence seemed to say, we can see what the errors in the simulation are now, but don't know how the same errors would manifest in another scenario - which doesn't say a lot really. Certainly, such a statement needs to be expanded on if it is to say. But the sentence doesn't say "we don't know what the errors are".
Well no it doesn't said that at all Steve. That's a projection of meaning on your behalf. |
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quote: Well no it doesn't said that at all Steve. That's a projection of meaning on your behalf.
I'm a reasonably intelligent person. Possibly the lack of context has made me unable to understand the original quote, in which case I need the full context to understand it. That might make it clearer as to the reason for its removal. Possibly I have misunderstood the quote in which case it should have been removed or expanded, since the document should be comprehensible enough to someone like me. |
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quote: Originally posted by insanity is hereditary:
QUOTE posted by steve m
Our contribution is, unfortunately, not "little".
Our entire contribution to amount of co2 that is in our atmosphere is only 0.25% of the total amount of co2 that is our atmosphere so to say that our contribution isnt little is rater misjudged! go on any climate sites and they will differ from one to another however the most cmmon number that comes up is the one that i said. however yes the amount of co2 has increase (not as much as many people think) but so have other gases and that has contributed! in this country alone cows produce more methane (which catchs more heat than co2) and co2 in this country than humans do from their cars ad plans! so the debate for co2 causing most of the global warming is rather native to think!
these arguments don't work on the believers Dude, Zealots will always believe no matter what you say about the smallness of their figures. Steve has made over 500 posts on behalf of a "science" based wholly in statistics yet we're "mostly NOT statisticians" Where the sense in debating at all?
they'll burn, burn, burn!!
like they did to the Anarchists
And it'll burn burn burn like the histories they stole from us
One day patriotic thugs will dance to songs of justice
And give apologies for immeasurably acted perfection...(Against Me!)
one day!
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quote: Steve has made over 500 posts on behalf of a "science" based wholly in statistics yet we're "mostly NOT statisticians"
Basic statistics is sufficient for a lot of discussion, such as allowing me to calculate, using published oil, coal and gas usage statistics, a rough figure that shows that humans have emitted more than enough CO2 to account for the observed 30% increase. When it becomes a detailed matter of attribution of widely observed climate change to a range of potential causes then the statistics becomes quite tricky - the principles aren't rocket science but the application is complex. cumdiver, I don't thing your pointless and insulting statements are helpful to your cause  |
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quote: Originally posted by realprimate:
Anyrate they compare the models with measurements and tune them accordingly.
Precisely my point. If you tune the models so that they agree with past reality, then it is hardly surprising that they agree with past reality. D'oh. But this then has the problem that they don't tell you about the future. What would be needed is to tune them on the basis of the first half of the data (say 1900-1950), and then see how well they predict 1950-2000. And until they do that I just do not take them seriously. |
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quote: Precisely my point. If you tune the models so that they agree with past reality, then it is hardly surprising that they agree with past reality. D'oh.
I don't think realprimate understands. Models comprise dynamical and physical formulations for many processes, that follow basic laws of physics, and parametrisations of certain other processes (such as clouds or sea ice) where features are too small scale to be modelled. The tuning of the model involves fixing the uncertainties in the model such that it follows a stable climatology (ie. no changes in atmospheric composition, solar, etc), and produces broad features of the earth (El Ninos, monsoons, the right amount of rain in the right place at the right time). Tuning of current models takes a long time (years for current earth system models - they are just starting to put together models for the 6th IPCC assessment report which, if it happens, won't report until 2017 or beyond). Models are not let loose on different scenarios until they are tuned. The theory is that a well-tuned model should then respond in a similar way to the earth when a perturbation is introduced. This theory can be tested by testing the model's response to El Ninos, volcanoes, 20th century changes in atmospheric content etc. and comparing with observations. I don't think they would be spending hundreds of millions on supercomputers around the world if they weren't confident in their use. |
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quote: Originally posted by mufcdiver:
these arguments don't work on the believers Dude, Zealots will always believe no matter what you say about the smallness of their figures.
Steve has made over 500 posts on behalf of a "science" based wholly in statistics yet we're "mostly NOT statisticians"
Where the sense in debating at all?
Logical, evidence-based arguments don't work on people who have made up their minds in advance, and especially on people who are happy to use figures known to be wrong by a factor of over 100. This is not statistics: it's a simple number. |
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When I first looked at ththis C4 science forum this morning there was a post with a reference to a site claiming to summarise Sceptic views. http://www.convenient-lie.com/information.htmlNow 4 hours later reference to the site and the associated posting have disappeared. Fortunately I'd taken note of the site address because I trust no one. |
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I noticed it too. I don't think the moderators like people plugging their own website. Just after GGWS came out I spent half an hour debunking stuff in a website linked to by a poster only for the original post and my hard work to be deleted!
Looks like yet another forum, though it only has one member.
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quote: Originally posted by Steve_M: quote: Precisely my point. If you tune the models so that they agree with past reality, then it is hardly surprising that they agree with past reality. D'oh.
I don't think realprimate understands...... The tuning of the model involves fixing the uncertainties in the model such that it follows a stable climatology (ie. no changes in atmospheric composition, solar, etc), and produces broad features of the earth (El Ninos, monsoons, the right amount of rain in the right place at the right time). Tuning of current models takes a long time .......
I think realprimate might very well understand. If the tuning involves really minor items, then why does it take a long time? The fact that it takes a long time rather suggests to me that the items are not minor. |
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quote: I noticed it too. I don't think the moderators like people plugging their own website.
There are levels of plugging and what I saw this morning was minimal and it did reference what purported to be one person's work on costructing a synthesis of scientific sceptic argument. And it was introduced into one of the relevant threads (I can't remember which).It wasn't awash with advertising. Maybe I'm just old fashioned and believe in reasonable freedom of expression but its seeming immediate removal does jar a bit. |
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quote: Originally posted by JL(SFC58,AFCB):
I think realprimate might very well understand. If the tuning involves really minor items, then why does it take a long time? The fact that it takes a long time rather suggests to me that the items are not minor.
Er. Got to hold my hand up chaps. Sorry. I was a bit too quick and flippant there (OK ignorant). Suffice to say post-surfing in google scholar showed me enough awesome complexity to make me severely backtrack. Should've saved the links for you. But there's been plenty of coverage that the present conditions can only be accounted for by adding anthropological emissions in the models. I'll stand by that (after I confirm by surfing and getting some refs for you).
God Bless Dave Rado!
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hi there guys,
the website in quetion was mine. It has a forum but thats just to aid any people whi have anay questions.
If you look on the right of the pages you see nad index of information. its about 18 pages long.
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quote: I think realprimate might very well understand. If the tuning involves really minor items, then why does it take a long time? The fact that it takes a long time rather suggests to me that the items are not minor.
No they are not minor items. Basically the model is run, the results compared with climatology and errors are found. Errors can be caused by interactions between the different components of a model. Often, tricky areas are around bunches of small islands, tall mountains and straits, since the land-sea mask does not resolve these features very well. More difficult problems might related to where two parts of the model may have incompatible formulations that, for instance, mean that El Nino's never form. These sorts of problems might be because the winds are a bit too strong, or the parametrisation of the impact of winds on waves is a bit wrong. These might feed into unrealistic amounts of mixing in the ocean. So the features are tweaked to make the physical representation more closely matched to what is observed. There has to be a physical basis for the fix - you cannot just add an El Nino subroutine that arbitrarily transports ocean heat from one side of the Pacific to the other, you have to understand the underlying physical flaws in the model, and fix them. And any fix you put in, say, to try and reproduce the causes of El Nino will also change what happens in all the other oceans in the world - so an unrealistic fix would fix El Nino but might break North Atlantic Oscillation. I know about the above because some of my friends are involved in building such a model. |
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quote: There are levels of plugging and what I saw this morning was minimal and it did reference what purported to be one person's work on costructing a synthesis of scientific sceptic argument.
I've had perfectly innocuous web links deleted from the middle of posts after the posts had appeared in full making the post read rather strangely. If Geowizard wanted to contribute to the debate in this forum by summarising his (wizards are mail aren't they) thoughts, that should avoid the censor and make it easier for us to respond. Perhaps being a paleoclimatologist he could comment on our thread on ice cores and accuracy of CO2 measurements. |
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quote: hi there guys,
the website in quetion was mine. It has a forum but thats just to aid any people whi have anay questions.
If you look on the right of the pages you see nad index of information. its about 18 pages So we knowlong.
Geowizard, I can't follow your paper because you do not include the references. Lindzen 2007 does not come up in Google scholar and nor does Rodwell and Palmer 2007 which sounds like an interesting paper (and I'd trust it since Rodwell is a friend of mine). You say: quote: The fact that the IPCC attempts to make a prediction on global climate for the next 20 years is absurd,
Is it so absurd given that the first IPCC report in 1991 included a projection which turns out to have come true. Your discussion of GHG theory is reasonable, but where did you get the figure that the models say the warming in the troposphere should be 2-3 times more than the surface. It seems a circular argument to say that since the warming in the troposphere is .1/decade then the surface warming should be .03 per decade, but it isn't so the models are wrong. I actually think your 2-3 times figure is wrong. You say quote: the general scientific consensus of scientists working in the area of solar activity is that solar activity namely sunspots attributes 0.45° C
This is not true and obviously wrong since we do not see such an obvious cycle in the recent temperature record. The variation over a solar cycle is less than 1W/m^2 much smaller than the forcing of current increases in CO2. That'll do for now as it's lunchtime. |
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quote:
Love it! 40 points for comparing those who argue against your ideas to Nazis, stormtroopers, or brownshirts.
40 points for claiming that the "scientific establishment" is engaged in a "conspiracy" to prevent your work from gaining its well-deserved fame, or suchlike.
40 points for comparing yourself to Galileo, suggesting that a modern-day Inquisition is hard at work on your case, and so on. |
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quote: Originally posted by TrueSceptic: quote:
Love it! 40 points for comparing those who argue against your ideas to Nazis, stormtroopers, or brownshirts.
40 points for claiming that the "scientific establishment" is engaged in a "conspiracy" to prevent your work from gaining its well-deserved fame, or suchlike.
40 points for comparing yourself to Galileo, suggesting that a modern-day Inquisition is hard at work on your case, and so on.
You missed out: 50 points for claiming you have a revolutionary theory but giving no concrete testable predictions. Just what I've been asking AGW-ists for. Tests of predictions against real world observations. Goodness-of-fit statistics and all that. |
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quote: Originally posted by Steve_M:
No they are not minor items. Basically the model is run, the results compared with climatology and errors are found. Errors can be caused by interactions between the different components of a model. .... I know about the above because some of my friends are involved in building such a model.
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