I really wish Gavin would put as much effort into getting the oddities with the GISTEMP dataset fixed rather than writing coffee table books and trying new models to show the sun has little impact.
This paper gets extra points for using the word “robust”. – Anthony
Solar trends and global warming (PDF here)
R. E. Benestad
Climate Division, Norwegian Meteorological Institute, Oslo, Norway
G. A. Schmidt
NASA Goddard Institute for Space Studies, New York, New York, USA
We use a suite of global climate model simulations for the 20th century to assess the contribution of solar forcing to the past trends in the global mean temperature. In particular, we examine how robust different published methodologies are at detecting and attributing solar-related climate change in the presence of intrinsic climate variability and multiple forcings.
We demonstrate that naive application of linear analytical methods such as regression gives nonrobust results. We also demonstrate that the methodologies used by Scafetta and West (2005, 2006a, 2006b, 2007, 2008) are not robust to
these same factors and that their error bars are significantly larger than reported. Our analysis shows that the most likely contribution from solar forcing a global warming is 7 ± 1% for the 20th century and is negligible for warming since 1980.
Received 17 December 2008; accepted 13 May 2009; published 21 July 2009.
Citation: Benestad, R. E., and G. A. Schmidt (2009), Solar trends and
global warming, J. Geophys. Res., 114, D14101,
doi:10.1029/2008JD011639.
hat tip to Leif Svalgaard
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7% of warming only? Then I am curious what caused so rapid increase of global temperatures between 1905-1940, when the gas-which-must-not-be-named was almost constant. Btw, warming IS negligible since 1980.
What will these people do after few years, when the downward trend will be more and more pronounced?
We use a suite of global climate model simulations for the 20th century to assess the contribution of solar forcing to the past trends in the global mean temperature.
Heaven forbid they use actual temperature observations correlated with solar cycle observations to assess solar forcing in the 20th century.
Maybe because it would demonstrate the naive application of outdated Fortran programs and show that the next grant request is nonrobust?
So the models do not include solar forcing??
**We use a suite of global climate model simulations…
Maybe I should still read it, or have I read too much?
When will someone measure something?
Have no interest in reading anything by Gavin.
Odds are its total crap.
Questions for those who actually read his stuff:
1. Does Gavin assume fabricated aerosol data to force his model to hindcast the cooling from ~1945-1975?
2. Is the sensitivity of his model greater than 1C (for a doubling of CO2)?
3. What is the magnitude of alleged natural temperature forcing, if any, relative to alleged humanmade forcing?
4. Does Gavin use GISStemp with all its warming bias as the basis for alleged observed temperatures?
*****************************
“We use a suite of global climate model simulations for the 20th century to assess the contribution of solar forcing to the past trends in the global mean temperature.”
So, instead of checking their assumptions, they checked against their assumptions.
We demonstrate that naive application of linear analytical methods such as regression gives nonrobust results.
I laughed out loud at that.
What he is saying is that our models aren’t just extrapolating a trend out into the future. They are of course, but to admit it would put Gavin and the other climate modellers out of a job. Drawing a straight line with a pencil and ruler is an awful lot cheaper.
What we know, you could write a paper, what we don’t know, would fill a library.
So we write papers.
When all that latent heat is dissipated-from ’98 on how will that be explained?
BTW the Sun is vewy,vewy quiet of late…
well nice of Gavin to use a grossly expanded vertical scale to increase the slope of his upward trend.
Why don’t you change the vertical scale Gavin to match the -90 to +60 C range of surface temperatures that can occur on earth under recent climate conditiosn.
And just what is the scale of that solar effect you have secretly dotted in there so you can’t see it ?
Since the outgoing surface radiation depends approximately on the 4th power of the local surface temperature (Kelvins; why not simply plot your trens on the Kelvin temperature scale; so we can see how totally insignificant it is.)
And how about those robust owl box locations you chaps use for your raw data; I particularly liked that academic masterpiece that stands outside the front door of the University of Arizona Department of Environmental “Science”.
George
Love these academic locutions.
“nonrobust” = “nyah nyah nyah”
/snarkoff
From a purely behavioural POV, defense, bet-hedging and CYA are the majority AGW position now, and that has to be good for real science and for those of us preparing for a couple of cold decades. Even the once-esteemed NYT is in on the act: Instapundit has linked a delicious article where the money quote from one D Hathaway is:
“We still don’t quite understand this beast,” Dr. Hathaway said. “The theories we had for how the sunspot cycle works have major problems.”
Even the NY Times, a big supporter of the IPCC story line, quotes a scientist as saying the solar/cosmic ray/cloud effect could have been 20% of the warming.
Many of us could have found scientists who might say the ratio was the other way, 80/20, solar/CO2.
http://www.nytimes.com/2009/07/21/science/space/21sunspot.html?_r=1&ref=science
Using a “suite of global climate model simulations” (which, by the way, do not appear to give reasonably accurate hindcasts) to assess the contribution of solar forcing is ridiculous. I believe TSI (and I’m sure Leif will jump in here if I’m wrong) has only been accurately measured for the last two or three decades… so what has Gavin been using as a proxy for solar “forcings”? I’ll have to read the paper, I suppose.
Oh yes. *Please*, Gavin; stop using the word “robust”. It’s been done to death, and is now sounding affected.
???????????????????????????????????????????
Note that temperature data end in 2000-look how the models are shooting off at that point. Now, after that, did the models continue to track? No, they didn’t.
Let’s see what Scaffeta and West have to say (any self respecting (HA!) Journal would give them the chance to reply.
And of course the use more Total Solar Irradiance only, PMOD only nonsense.
But, I should point out that one mustn’t fall into the “if it isn’t the sun, it’s AGW” trap. None of these changes are of a magnitude requiring “explanation” by “forcings” at all.
Hey Gavin, where are your measurements of cloud cover to prove positive cloud feedback? And how do you know that warming causes the clouds to change and not the other way around?
Oh wait, you don’t. Because there aren’t really that many measurements of clouds at all. Which makes your entire narrative very speculative methinks…
Gavin Schmidt publication at JGR coincides with the NOAA and GISS tarmac measurements… all this is smoke screen for Copenhagen. I hope someone will demonstrate the inanity of his paper…
We use a suite of global climate model simulations for the 20th century to assess the contribution of solar forcing to the past trends in the global mean temperature.
I actually did not go beyond this statement. If I remember rightly, don’t most of the solar scientists who used the past to model SC24 now have egg on their collective faces?? I guess mankind never learns the lessons of history and are doomed to repeat it. Et tu Gavin.
How do they represent the solar forcing? Simply by a slight 0.1% variation in TSI?
I doubt their models include a coupled magnetohydrodynamic/cosmic ray/cloud nucleation representation.
But Anthony, you’re promising to do such a thorough analysis of the GISS, why would he work on that when you’re doing it for him and he can assess your work.
I’m with Allen (15:31:09). I read as far as “global climate model simulations” and know it’s just going to me more Schmidt rubbish. When he decides to join the real world of science, then I’ll read his work.
Why does the graph stop at 2003?
It would be nice if Gavin would spend some valuable time doing something really useful: Like getting out of the office and seeing to the siting issues.
Another would be to de-correct the unoffending stations and drop the useless concrete/asphalt/heat source thermometers.
If we wanted to see what was really going on at the surface, we’d be looking at Infrared images from imaging satellites and aircraft.
The sun is very quiet, indeed.
Just wait until winter hits with this going on.
Maybe Gavin could give us the RAW data, and let us correct the offending stations to the good ones. Then lets compare results.
GSTEMP is like me buying a bunch of apples for a pie. I find a couple of bad ones, but instead of throwing out the bad apples, I induce the good ones to rot. Wouldn’t want my pie to be inconsisent or taste nice.
It’s clear Gavin isn’t clued up on the sun.
Here’s something I’ve been working on this evening. Still a work in progress, but it’s getting there.
http://s630.photobucket.com/albums/uu21/stroller-2009/?action=view¤t=ssnc-pdo-amo.gif
From their introduction.
“The paper is divided into 2 parts, of which the first explores
the danger of applying linear statistical methods to data
from a complicated and chaotic system.”
They start out admitting climate is chaotic. Then they proceed to do an analysis by making use of climate models.
I doubt they can model chaos. If they can’t, the model results don’t represent reality. If they can, each time they run the models they would get a different result. In either case I don’t see how the analysis can be reliable. Especially when they have to guess at the forcing values and their relationship to each other.