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#26384 06/03/08 01:53 PM
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I have found it quite amazing that there has not been more challenge of the IPCC (model based) predictions of global temperature rise. Given the continuous barrage of messages of impending doom, I have always found it surprising that there is not more criticism of past predictions. Surely, if we can't get it right in the short term it doesn't lend a lot of credibility to the long term.

The 2001 IPCC report(TAR) has now been long enough ago to make a reasonable comparison of the range of predictions against the actuals. Attached below is the view of this comparison.




I still have not had it explained to me by anyone how the actual temperatures could fall outside the ENTRIRE RANGE of the 2001 predictions.

http://i28.tinypic.com/f4iqnm.jpg

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Don't forget that our CO2 emissions have exceeded those included in scenario A2. We so not even qualify for the lowest 'constant emissions' scenario. There has been much discussion especially about the 2007 ar4-wg1 report and how the models that created their scenarios have falsified. Of course, those at realclimate use a weaker test to prove that the current temperatures are consistant with the models; however, they also use vastly different error bars than what are shown in your graph. Probably 2 years ago now, I asked about the error bars on a graph similar to the one to which you link, and I was told that those were not the 95% error bars.

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ImranCan
I had recently seen a similar chart on the internet and thought that there might be a connection.

on this chart there is quite a bit of similarities between the two charts

!
I know that this chart is about money and the chart above is about rising temperatures , would you say that the similarities
are obviously connected or just coencidental?

Exxon Mobil stock prices from 1970 - present.

if you look at the IPCC chart for the year 2005 you will notice
there is a decrease in the temperature increase up to the present year 2008.

if you will notice the Exxon Mobil Oil chart you will notice that there is a sharp increase in stock prices begining in the year 2003 to present 2008.

could it be that the largest oil consumer (the U.S.A. ) has stopped consumming quite so much given the increased gas prices?

along with a gradual increase in solar power usage and smart energy products and programs.

Quote:
I still have not had it explained to me by anyone how the actual temperatures could fall outside the ENTRIRE RANGE of the 2001 predictions.


I believe that there are thousands of effects that can change any climate predictions to a great degree if not accounted for.

the reason you have not had this explained to you is probably because the work being done is a work in progress , and there are no stamped in steel answers to give to you.

there are so many diversities involved that interact between themselves raising and lowering temperatures , one effect that cools subtracts from others that heat and vice-versa.

trying to provide a chart or prediction on global temperature without including everything and I mean EVERYTHING that could raise or lower global temperatures was an undertaking that was in its infancy and will be trial and error as different effects are found.

if you ask me they did a excellent job given the data they used.





Last edited by paul; 06/06/08 02:27 AM.

3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
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I've been resisting a reply here, but....

I just wanted to point out that this (like your ice graphs)
is measuring the anomaly, not the temperature.

This would be better viewed as a bar graph;
a bar for each year's divergence from average.
Each year (except '84-85) is above average.
A downward dip just means it's not as much above average as the preceding year.
In general, the trend is upward.

You've got '08 on the graph already?
It looks like the "first 4 months" already are as warm as all of 1990 & 2000.

Quote:
I still have not had it explained to me by anyone how the actual temperatures
could fall outside the ENTRIRE RANGE of the 2001 predictions. -ImranCan

The predictions are for trends; not a specific year, for which
"actual temperatures could fall outside" (above or below) any predicted trend.
===

Let's wait for the end of 2008 before including it in a "rolling 5 year average,"
and then proclaiming a significant deviation.
Maybe it'll get warmer as summer '08 unfolds.

smile

p.s. Also note the inset graph on the lower right.
Again, like the ice graphs, we're talking about a hugely
magnified, tiny end segment, of a very large graph.


Pyrolysis creates reduced carbon! ...Time for the next step in our evolutionary symbiosis with fire.
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Originally Posted By: samwik
A downward dip just means it's not as much above average as the preceding year.
In general, the trend is upward.


The top label of the graph says Global Average Temperatures. They are Anomolies of the temps and not the trends. If you add the 1961-1990 average temp to each point, you will get the HadCRUT measured/adjusted temperatures. You can tell the trend by looking at the slope of the pink average line. Even if you ignore 1998, the trend has leveled. It has been beyond the (whatever level of) error bars that were drawn by the IPCC. Seeing as how we do not qualify for the lowest scenario, or even the highest scenario for that matter, the point is that the ensemble of models used by the IPCC have falsified. Determining the level of error bars is important to figuring out how significant it is. Of course, that biocab link I provided on the other thread already discusses why: CO2's radiative forcing is not significant enough.

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CO2? ....Explained at biocab?
Fortunately this has nothing to do with CO2,
so we don't have to bring up that entertaining site.


Hi John,
Thanks for the information about how they calculated their average.

Thanks for the quote; did you have a question about it?
When I said "the trend is upward," I was referring to the pink line,
the product of a "rolling 5 year average."

Shouldn't a "rolling 5 year average"exclude 2008 (winter months only)?

Originally Posted By: JMR
It has been beyond the (whatever level of) error bars that were drawn by the IPCC.
Really?
How do we know that? Do you have a link?

[update]
Whoops, I see. The lowest red line is the lower limit of those "error bars." Is that correct?

meanwhile....
The trend occasionally heads gently downwards, as in 1981-84, 1989-91, 1997-98, and 2000-01.
Do you think this newest update, with the partial 2008 data,
indicates that we're about to head down a steep slope?
Why would this be any different than those other occasional slowdowns
in the rapid upward slope of that pink line.

I think the important thing to compare is the slope of the pink line
and the slope of the different IPCC projections.
Which one matches the closest? I'd eyeball it as slightly steeper than the black line,
but not nearly as steep as the dashed-red line. Does that seem right?

smile

p.s. This weekend... CO2, finally (hopefully).

Last edited by samwik; 06/06/08 08:10 PM. Reason: add p.s.

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Glad to see you've got your chart up ImranCan.

It's a little fun to see people twisting in the wind, trying to explain away the dreadful model preformance that these GCMs have.

Too many people simply don't understand modelling, and think of it as a tool to explain the unknown. Models are worth nothing if you don't understand the underlying processes. Everybody should repeat that 10 times.

These are highly parameterized models, which means they have turned enough knobs, far enough, that they were able to replicate past climate (this is commonly known as the "calibration phase"). It doesn't say anything about the model's ability to predict future climate, just that the model can replicate past climate well. What most (all?) GCMS are missing, is the verification phase of modelling. This is where, prior to calibration, the modellers set aside a portion of the time period,which they don't even consider, or look at, during calibration. Once they are satisfied with their calibration, they test, or verify, the models ability to replicate climate in this time period that was set aside. For example, the entire modelling period of 1850-present, you'd calibrate with the time period of 1850-1980 or so....and then verify from 1980-2000. If the model was able to accurately predict the climate in the 1980-2000 using the only the parameters that you calibrated to in the 1850-1980, you'd say the model predictions were verified.

This is the only way you can test the model's ability to replicate climate. But did they do this? Of course not. They twisted enough knobs, introduced enough fudge factors (google "flux adjustment") until the GCMs matched the observed temp record from 1850-present.

And it worked..... the gullible, uneducated media and public ate it up. Wow, look how good the model fit is! The model's must be right!! Until that is, enough time had passed where you could actually go back and see how well they preformed against recent temperature data. As ImranCan is showing..........it's pathetic.

By the way, now that the difference between anomalies and trends have been explained, I guess I can show the following chart. This is global avg temp from the RSS satellites, the temperatures for May have just been released. All 5 months in 2008, have been pretty much right at average. Doesn't look like those GCMs are getting any better at predicting future climate.

I just got Office 2007.....you can make charts look real pretty now smile

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Originally Posted By: samwik
Shouldn't a "rolling 5 year average"exclude 2008 (winter months only)?


I like how you mentioned that the first 5 months of winter temps should be excluded. That is funny. I assume you are being ironic though because it is only winter for half the planet during those months.
Of course, the Southern Hemisphere was in summer until the end of March.

Yes, I was taking the "IPCC2001: lower bound of entire range" line to be the error bar.

Originally Posted By: samwik
I think the important thing to compare is the slope of the pink line
and the slope of the different IPCC projections.
Which one matches the closest? I'd eyeball it as slightly steeper than the black line,
but not nearly as steep as the dashed-red line. Does that seem right?


No, you cannot just compare the slope of the pink line and the slope of model ensemble projections. As Canuck eludes, the parameters for each scenario need to be considered. We do not qualify for the lower lines. Actually, we don't even qualify for the "highest published scenario" line. Our CO2 emissions have exceeded even those that were used for their top line which was their worst case scenario. To compare it to the lowest scenario line or the "IPCC2001: lower bound of entire range" line is to admit that the models did not account for CO2 properly. It is to admit that other parameters, perhaps those not included in the models like clouds, are more important.

In light of the models falsifying, the conclusions of the IPCC reports must also be ignored.

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Originally Posted By: John M Reynolds

In light of the models falsifying, the conclusions of the IPCC reports must also be ignored.


Given that the 2001 models have falsified (and it was the 2001 models of which much of the hype was built), it makes me wonder why its all being ignored .... and I find it fascinating to see how this plays out politically. What is it going to take to get us out of this pseudo-religious AGW hole we have dug for ourselves ?

It may seem as though the global bandwagon has really taken off - the IPCC 2007 report, Bali 2007 (which I think history will show as the AGW high point - although I found the schoolboy tactics by which the rest of the world shamed the USA completely disgraceful), Australian Kyoto signatories etc etc

..... but I think we must remember that politics are a good few years behind the curve. There are a number of factors which are now coalescing - : the increasingly obvious falisifcation of the 2001 models, the current global cool 'snap', the plethera of new books that has hit the shelves trashing the AGW consensus (Nigel Lawsons book is in the top 10 of Amazons Science and Nature bestsellers - ironic becasue it actually an economics book), the biofuels fiasco etc etc. It will take time for the political situation to adapt but my guess is that the planned end 2009 Copenhagen meeting (Kyoto follow-up) may see the total disintegration of any form of 'consensus'. Too many people will be having too many doubts by then.



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Originally Posted By: samwik
I've been resisting a reply here, but....
still I relent. frown

Yes, it is the slope that is important.
I can compare the two slopes; why do you say "you cannot just compare the slope" of the two lines?

"Fudging" the starting time by a couple of years isn't a big deal, is it?
Is this the kind of thing you mean by "falsifying?"

ImranCan's handwaving aside....
The slope, "the rise over the run," endures!

smile


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Originally Posted By: samwik
why do you say "you cannot just compare the slope" of the two lines?


Because we don't qualify for the bottom 2 scenarios. The top A1F1 line is the non-mitigation scenario where CO2 is allowed to increase. Our CO2 emissions have exceeded those incorporated into that scenario, thus we don't qualify for the bottom IS92a line on the graph. To suggest that we can compare the slope of the pink (reality) line to that of the lowest scenario line is to suggest that the assumptions for the higher sloped lines were incorrect. The most significant assumption was that temperatures would increase if CO2 levels increased.

Falsify "3. To declare or prove to be false."

There is no need to spread fear, uncertainty and doubt. There was no fudging of the starting time. The ensemble of models used by the IPCC have been shown to be inaccurate in their predictions that started in 2001. None of the scenarios they presented have accurately represented the real world. This is the point of the original post above.


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