From their Die kalte Sonne website, Professor Fritz Vahrenholt and Dr. Sebastian Lüning put up this guest Post by Prof. Jan-Erik Solheim (Oslo) on Hansen’s 1988 forecast, and show that Hansen was and is, way off the mark. h/t to Pierre Gosselin of No Tricks Zone and WUWT reader tips.
Figure 1: Temperature forecast Hansen’s group from the year 1988. The various scenarios are 1.5% CO 2 increase (blue), constant increase in CO 2 emissions (green) and stagnant CO 2 emissions (red). In reality, the increase in CO 2 emissions by as much as 2.5%, which would correspond to the scenario above the blue curve. The black curve is the ultimate real-measured temperature (rolling 5-year average). Hansen’s model overestimates the temperature by 1.9 ° C, which is a whopping 150% wrong. Figure supplemented by Hansen et al. (1988) .
One of the most important publications on the “dangerous anthropogenic climate change” is that of James Hansen and colleagues from the year 1988, in the Journal of Geophysical Research published. The title of the work is (in German translation) “Global climate change, according to the prediction of the Goddard Institute for Space Studies.”
In this publication, Hansen and colleagues present the GISS Model II, with which they simulate climate change as a result of concentration changes of atmospheric trace gases and particulate matter (aerosols). The scientists here are three scenarios:
A: increase in CO 2 emissions by 1.5% per year
B: constant increase in CO 2 emissions after 2000
C: No increase in CO 2 emissions after 2000
The CO 2 emissions since 2000 to about 2.5 percent per year has increased, so that we would expect according to the Hansen paper a temperature rise, which should be stronger than in model A. Figure 1 shows the three Hansen scenarios and the real measured global temperature curve are shown. The protruding beyond Scenario A arrow represents the temperature value that the Hansen team would have predicted on the basis of a CO 2 increase of 2.5%. Be increased according to the Hansen’s forecast, the temperature would have compared to the same level in the 1970s by 1.5 ° C. In truth, however, the temperature has increased by only 0.6 ° C.
It is apparent that the next to it by the Hansen group in 1988 modeled temperature prediction by about 150%. It is extremely regrettable that precisely this type of modeling of our politicians is still regarded as a reliable climate prediction.
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There has not actually been such as a 0.6 degrees Celsius temperature rise since the 1970s.
Rather, as can seen looking at UAH satellite data, such as http://www.drroyspencer.com/latest-global-temperatures/ , meaningful global temperature increase since 1979 has been 0.3 to 0.4 degrees Celsius at most.
Compared to Hansen’s prediction (even his scenario B being about 1+ degrees Celsius, let alone scenario A and above), that is multiple times less. That would fit a climate sensitivity accordingly less than his claims and also far less than the climate sensitivities still used by alarmists today in their current predictions. That is even before what would happen if one rather takes into account natural influences, like how the AMO/PDO predominantly increased over that period, leaving less of a temperature signal to be accounted for by manmade causes, let alone also considering solar and GCR changes. (Actual climate sensitivity: http://www.sciencebits.com/OnClimateSensitivity ).
Without high climate sensitivity, without being able to claim future warming greater than the beneficial Holocene Climate Optimum, the basis of CAGW collapses.
The global warming movement utterly hates the term CAGW because it blows the dishonest binary thought fallacy they love* by rather breaking the matter down into its true nature: For what they want, global warming has to be:
Catastrophic, not beneficial like the Minoan Warm Period, etc. … else nobody cares.
Anthropogenic primarily … else that defeats the point**
Global
Warming
* (That was the whole basis of Doran & Zimmerman 2009 dishonesty, for example, getting a 97% “consensus” by 2 survey questions of if the Earth warmed since what was the Little Ice Age and asking if humans have a scientifically significant as in non-zero effect — when even having a black or white roof has technically a non-zero effect).
** The point is trying geoengineering by an agent (CO2) chosen for exceptionally low ineffective radiative forcing per ton (some other agents orders of magnitude more cooling radiative effect per ton just as some orders of magnitude more warming effect per ton), maximum harm from its rationing to the industrial basis of prosperous high-consumption modern civilization which these guys hate, and maximum complex biological side effects as in harm to agriculture and plant growth from its reduction.
Jerome
See http://tinyurl.com/29e53y, Figure 2. Forcings are in Figure 1. Observations have been very close to Scenario B. You are, quite frankly, contradicted by the data.
So the Montreal Protocol came out in 1987, yet Hansen in 1988 assumed a growth rate of 3% per year for CFCs? That Hansen guy is really sharp.
@ur momisuglyBill Illis says:
June 15, 2012 at 5:08 pm
GHG assumptions (Scenario A had CO2 at 393 ppm for 2011 while B was at 391 ppm – Actual was 390.44):
===================
While I sometimes I only read WUWT posts in the hope of locating a comment or two from you… 😉
I note that: NOAA has CO2 levels at 2011 @ur momisugly 394ppm and 2012 @ur momisugly 396.78ppm
http://www.esrl.noaa.gov/gmd/ccgg/trends/
Which still implies that actual CO2 output has been above scenario A if I read you correctly.
The warmist here are arguing that based on “actual” forcings scenario b is the correct one and that is pretty close if you correct for a mistakely too high sensitivity.
But one should lok at the source o0f the “forcing” corrections. Since Hansen’s 1988 predictions it has been clear that climate models overstating the temperture increase. The choices were to re-evaluate the models and therefore reduce sensitivity or to find other factors which would change the forcings. So since 1988 alarmist climate scientists have been searching for anything which could plausibly lower the net forcing. They have come up with Chinese aeresols and now CFC’s. Basically they are tuning the inputs to force the output to get closer to reality.
The logic is, “The models are right but reality does not match their output so what other factor have we missed that might fix the growing divergence.” Of course the idea that the models are wrong is not even considered.
This mind set is a classic example of confirmation bias.
Actually, averaged annual data here, which is much better:
ftp://ftp.cmdl.noaa.gov/ccg/co2/trends/co2_annmean_mlo.txt
Will Nitschke says:
June 15, 2012 at 3:40 pm
A couple of further observations. The two standard defences of the Hansen 1988 prediction are:
(1) Other greenhouse gases did not rise at the levels forecast by Hansen
(2) CO2 has not increased at the level predicted by Hansen’s scenario (a)
I have in the past researched both claims. For (1) the IPCC does describe the contribution of various greenhouse gases to estimated warming. The total of all other gases combined amounts to about 10% of the contribution of CO2 if my memory is correct. (If I am wrong here, please refresh my memory). It was, anyway, a very minor component of the forecast. If you want to be as fair as possible to Hansen, then reduce the 150% over-estimate by around 10%
To refresh your memory check out Fig 2 in the 88 paper, you’ll see that the forcing for the ‘other trace gases’ is far more than “10% of the contribution of CO2”.
[snip – Dana Nuccitelli – save the sanctimonious lecture as to what you think skeptics should do, I’m really not interested in your thread bombing here. Go write a smear at SS – Anthony]
jknapp says:
June 15, 2012 at 5:54 pm
“The warmist here are arguing that based on “actual” forcings scenario b is the correct one and that is pretty close if you correct for a mistakely too high sensitivity.”
I know you’re just remarking on that in passing and may not have seen my recent prior comment yet. However:
Even if just pretending that temporarily for the sake of simple argument, Hansen’s scenario B is about 1 degree. Actual meaningful net warming since the end of the 1970s is 0.3 to 0.4 degrees Celsius as can be seen from this:
http://www.drroyspencer.com/wp-content/uploads/UAH_LT_1979_thru_May_2012.png
If absurdly, we pretended there was zero warming from natural causes meanwhile (no PDO/AMO rise existing, etc.), that would still make Hansen’s climate sensitivity around a factor of 3+ times too high. The climate sensitivities used by alarmists today are not 3+ times less than Hansen’s. That’s still just blatant creative lying and no excuse.
“Basically they are tuning the inputs to force the output to get closer to reality.”
Indeed. It would get even more ludicrous if they were to try to explain relatively non-fudged temperature data like the pattern in this with such:
http://earthobservatory.nasa.gov/Features/ArcticIce/Images/arctic_temp_trends_rt.gif
William,
On the Observational Determination of Climate Sensitivity and Its Implications
We estimate climate sensitivity from observations, using the deseasonalized fluctuations in sea
surface temperatures (SSTs) and the concurrent fluctuations in the top-of-atmosphere (TOA) outgoing radiation from the ERBE (1985-1999) and CERES (2000-2008) satellite instruments. …
I think the importance of of climate sensitivity is that it provides the missing link in heat absorption. If you build the sensitivity then there there is an unexplained sink somewhere to frighten politicians.
However, satellite imagery shows the extra CO2 is being absorbed by plants, such as old forest trees becoming wider in their girth. Other studies tend to confirm this, so that countries like Australia are actually net CO2 absorbers.
http://www.john-daly.com/co2-conc/ahl-co2.htm
In that respect, this has been a brilliant manoeuvre to keep people off the track about the actually effect of increasing CO2.
Henry Clark says:
June 15, 2012 at 6:19 pm
Even if just pretending that temporarily for the sake of simple argument, Hansen’s scenario B is about 1 degree.
Why would one pretend that instead of using the actual value he shows in Fig 3?
Phil. says:
June 15, 2012 at 6:06 pm
To refresh your memory check out Fig 2 in the 88 paper, you’ll see that the forcing for the ‘other trace gases’ is far more than “10% of the contribution of CO2″.
Then why should we be bothered about worrying about CO2 at all. It appears to be harmless. Hansen said this: (see section 4.1 of the paper).
“Scenario A assumes that growth rates of trace gases emissions typical of the 1970s and 1980s will continue indefinitely;”
CO2 actually did increase at a greater rate from 1988-2011, compared to 1970-1988 (if only slightly) and no warming. Much ado about nothing it seems.
[like with Dana Nuccitelli’s sanctimonious lecture, yours is even worse. I’m just not interested in engaging you anymore given the way you treat me and other WUWT denizens elsewhere – be as upset as you wish – Anthony]
dana1981 says:
June 15, 2012 at 6:16 pm
The problem with ‘skeptics’ here is that all you care about is “Hansen was wrong” (one commenter above admitted exactly that). Well of course his model was wrong – all models are wrong. The useful question is not whether it was “wrong”, but what we can learn from it.
**********
I think we have learned that we shouldn’t be spending money on this nonsense. People can believe whatever they want, but when governments and NGO’s start imposing their belief system on private citizens, through taxes and other costs, based on little more than wild assumptions and doomsday scenarios, we have a right and a duty to question them.
You admit, “Hansen was wrong.” Has Hansen ever admitted this? Why are we wasting billions of dollars on this folly? It boggles the mind.
He works at NASA so the average person believes him anyway.
dana1981 says:
June 15, 2012 at 6:16 pm
“If you actually check to see by how much it overestimated the temperature change and calculate the equivalent sensitivity for real-world temperature changes, it’s right around 3°C.”
===============
You sound like my investment adviser.
If as KR and others say that Hansen’s predictions used too high a sensitivity etc. How do they continue to remain silent against claims from the alarmist community that “It’s worse than we thought” when clearly newer data is revealing it to be very much better “than they thought”?
I always use the global CO2 mean. Mauna Loa is close but is not the global average.
ftp://ftp.cmdl.noaa.gov/ccg/co2/trends/co2_annmean_gl.txt
scarletmacaw says:
June 15, 2012 at 5:52 pm
Phil. says:
June 15, 2012 at 1:28 pm
Why don’t you actually read the work you criticize? Hansen used the data on CFCs from the Chemical Manufacturer’s Association for F-11 and F-12 in scenario A ( a growth rate of 3%/yr).
So the Montreal Protocol came out in 1987, yet Hansen in 1988 assumed a growth rate of 3% per year for CFCs? That Hansen guy is really sharp.
It didn’t go into effect until 1989, the scenario A assumed the continuation of the existing growth rate, scenario B assumed a reduction in emissions with elimination of CFC emission by 2010, scenario C assumed an earlier elimination by 2000.
dana1981 says:
June 15, 2012 at 6:16 pm
For the record, despite Solheim’s poor analysis, it is true that observed temps have been closest to Scenario C, while emissions have been closest to Scenario B. What this tells you is indeed that Hansen’s model was “wrong” – meaning its sensitivity was too high.
==============================================================
ME: The Wizard of COz was rubbing his crystal ball based on CO2 emissions, not all emissions. He and his model was, and continues to be, just plain wrong. (That little dot at the end of the sentence is a PERIOD!)
===============================================================
The problem with ‘skeptics’ here is that all you care about is “Hansen was wrong” (one commenter above admitted exactly that). Well of course his model was wrong – all models are wrong. The useful question is not whether it was “wrong”, but what we can learn from it. And what we can learn from it is that climate sensitivity is probably less than 4.2°C, and probably close to 3°C. The problem with ‘skeptics’ is that you get stuck at “Hansen was wrong” and thus don’t learn anything useful from the exercise. And if you’re not going to learn anything useful, then why do it?
================================================================
ME: I admit. I haven’t learned anything new. I already knew that it’s foolish to bet a few trillion dollars on a surely wrong thing.
=================================================================
Well, of course the answer to that question is to reaffirm your belief that “Hansen was wrong”. But if you were real skeptics, you would actually try to learn something useful from the exercise. The problem is, what you learn is very inconvenient for your beliefs, so you just stop thinking before it becomes inconvenient.
===================================================================
ME: (See preceeding) I already knew not to bet on a losing proposition before it became “inconvenient”.
Should we shut down coal powered power plants based on a climate model that is WRONG?
Should we mandate mercury filled light bulbs in childrens’ bedrooms based on a climate model that is WRONG?
Should North Carolina spend millions of dollars to protect their coast from sea level rise predictions based on a climate model that is WRONG?
Should we surrender authority to the UN based on a climate model that is WRONG?
Have the warmist learned the answer yet?
We already knew.
Hansen’s 1988 Scenario B forecasts are really no different than the IPCC forecasts from its first report in 1990. So, while some people like to “believe” the sensitivity was too high or “make up any other rationale”, the global warming forecasts are farther off the more you go back in time.
The IPCC AR5 forecast submitted this year is even off by 0.2C even though they knew the actual temperatures for 2010/2011.
The forecast from one year ago is too high and the forecast from 20 years ago is 100% too high. Play with the numbers anyway you like. But ALL the global warming forecasts are too high whenever they were made.
All of this discussion appears to miss some very important points.
Forcings, as observed, as driven by economics, are around Scenario B, the most likely outcome according to Hansen 1988.
The data is available (http://www.esrl.noaa.gov/gmd/aggi/), as I noted before, for anyone taking the effort to look. Comparing temperature observations to Scenario A is really quite absurd, and IMO reveals those making such a strawman comparison as more interested in rhetoric than science.
Enough said.
As soon as I see the name “Hansen” I lose interest. He has been wrong about everything I have ever investigated.
What has the man been right about? Can anyone name a single thing?
The man manages to be wrong about things it is very hard to be wrong about. For example, I hate strip mining, but as soon as Hansen speaks, he makes strip mining look saintly.
The very fact this guy is not in jail, and instead has status and wealth, seems proof being wrong pays.
Meanwhile, where does honesty get the average guy? Fired, more likely than not, and therefore the honest guy buttons his lip. However, the ballot is still a secret ballot. It is still the place an honest guy is allowed to speak the truth.
I hope and pray Truth prevails, and decent and honest people vote out those who allowed the likes of Hansen to —self snip—.
“What would be interesting is this. It would be interesting to take a newer version of ModelE ( sensitivity is 2.7) and re run Hansens experiment with the following inputs”
1) scenario A, B and C
2) actual forcings during the observation period.
—
What would be more interesting is if we actually knew what differential equations Model E was solving (along with their numerical methods). The code is poorly documented junk…
“The IEA assumed in 2008 that future emissions would grow from 2005 to 2030 at 1.5% per year. “Actually, from 2005-2010 emissions increased by 2.4% per year (data from PBL in this PDF). The 1990 to 2010 average was a 1.9% increase per year, and 2009 to 2010 was a whopping 5.8% increase.”
Just a couple of questions.Would that include the “missing”1.4-billion tonnes here in 2010?
And if China got it so wrong in 2010, what other years did they get wrong?
http://www.scientificamerican.com/article.cfm?id=china-emissions-study-suggests-clim