Climate sensitivity

Evidence that the IPCC's models' temperature predictions haven't been very good.



If the models are wrong, then perhaps the underlying science behind them is also wrong. Afterall, the entire reason for modelling is to see what happens under certain conditions. And the model must accurately reflect the environment its trying to simulate. If it cannot do that, then no amount of parameter tweeking or modified conditions will make it more accurate.

The IPCC role is to “…to assess on a comprehensive, objective, open and transparent basis the scientific, technical and socio-economic information relevant to understanding the scientific basis of risk of human-induced climate change, its potential impacts and options for adaptation and mitigation…” [emphasis added]. Thus there was never any intent to pursue even the possibility of natural sources of "climate change" even though the earth's climate has been changing for billions of years. The scientific basis for natural climate change was - and remains - entirely out of bounds. Further, the IPCC quickly focused on only one "human-induced" source - CO2. Thus models virtually ignored other possibilities. This is most likely why the models have done so poorly - they've focused on the wrong climate change driver. (Truth be told, there are probably dozens, if not hundreds, of climate drivers)

 

"James Hansen said the average U.S. temperature had risen from one to two degrees since 1958 and is predicted to increase an additional 3 or 4 degrees sometime between 2010 and 2020."

“Within 15 years, global temperatures will rise to a level which hasn’t existed on earth for 100,000 years”.
James Hansen 1986

“By the year 2050 we’re going to have tremendous climate changes, far outside what man has ever experienced.”
James Hansen 1989

"We've got to ride the global warming issue. Even if the theory of global warming is wrong, we will be doing the right thing …"
Timothy Wirth

 

Yerssss! Sourced from WUWT and cherry picked to a fare-thee-well. Oh I admit the IPCC did not foresee the downturn in solar activity but then who did?

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The question was the accuracy of IPCC models. Showing a chart of those predictions is anything but "cherry picking" - regardless of where the chart came from.

OTOH, showing data only from 1970 (one of the lowest temperature years in the last half of the century) is a great candidate for cherry picking. Showing temps from 1940 (a high and also cherry picking) doesn't look nearly as dramatic - does it?



And showing tempature trend lines from uneven numbers of years is certainly cherry picking. Why not pick years when the temperature changed at the same rates?

Period Length Trend
(Degrees C per decade) Significance
1860-1880 21 0.163 Yes
1910-1940 31 0.15 Yes
1975-1998 24 0.166 Yes
1975-2009 35 0.161 Yes

"...the warming rates for all 4 periods are similar and not statistically significantly different from each other." Interview with Dr Jones in 2010 on BBC News web site.

Believers in the AGW hypothesis seem to ignore the lack of statistically significant temperature changes in all four accepted sources.

For RSS the warming is not significant for over 23 years.
For RSS: +0.127 +/-0.134 C/decade at the two sigma level from 1990

For UAH the warming is not significant for over 19 years.
For UAH: 0.146 +/- 0.170 C/decade at the two sigma level from 1994

For Hadcrut3 the warming is not significant for over 19 years.
For Hadcrut3: 0.095 +/- 0.115 C/decade at the two sigma level from 1994

For Hadcrut4 the warming is not significant for over 18 years.
For Hadcrut4: 0.095 +/- 0.110 C/decade at the two sigma level from 1995

For GISS the warming is not significant for over 17 years.
For GISS: 0.111 +/- 0.122 C/decade at the two sigma level from 1996

Or one could look at temps of overlapping 15 and 20 year periods to eliminate "selective" periods.





This would be how a skeptic looks at anthropogenic global warming.

 

Same tune is being played by a different orchestra.

 

Notice how you have taken only a few years of data

 

American view of the world


meanwhile in reality - here are the signatory countries to Kyoto

http://en.wikipedia.org/wiki/List_of_parties_to_the_Kyoto_Protocol

 

Why is this guy better than the two faced, lying Mod Edit ~ Rule 9/Circumventing profanity filter that preceded him?

[video=youtube;Cg7T8Kmb0b0]http://www.youtube.com/watch?v=Cg7T8Kmb0b0[/video]

Answers on the back of a postage stamp.

 

Another day, another false and misleading graph posted by a climate denier, who must think the rest of us are chumps as gullible as the readers of WUWT are.

Sorry, lucas, but some of us just aren't as dumb as the folks in Deniersville. Since you posted the graph, it's up to you to defend it. So here are a few questions:

* The IPCC First Assessment Report (FAR, 1990) actually contains 12 possible projections based on three different values of climate sensitivity and four different scenarios for greenhouse gas emissions. Which one of those twelve did you (or your denier pals) choose as the "1990" projection in the graph above?
* Which of the four emissions scenarios projected in 1990 turned out to be the closest to the truth, in terms of total radiative forcing?
* What is the predicted rate of surface temperature warming during 1990-2015 from the 1990 FAR with the IPCC's "best" estimate for sensitivity, combined with the known best projection of emissions?
* What is the actual rate of surface warming since 1990, and what is the 95% CI of that measurement?
* If the projection warming rate from 1990 (given the best sensitivity and best emission scenario) is within the actual 95% CI, does that count as a "hit" for the climate models of 1990, or a "miss", in your estimation?
* The FAR model runs actually begin in 1985 rather than 1990. Why does your graph cherry-pick 1990 as a starting date? Isn't that because 1990 is a warmer-than-trend year, deliberately chosen to make the models look bad? Do you think that kind of trick is honest, or deceptive? Wouldn't have been correct to start the model runs in the middle of the regression trend line rather than cherry-pick a peak (or valley) year?

Answer those for starters, and then we can move on to the Second Assessment Report.

And since the models are right, doesn't that imply that the science behind them is right?

 

Name someone who denies climate?

 

When I use the term "climate denier", I mean anyone who:
* denies that the earth is currently warming; OR
* denies that humans are the primary cause of the current warming; OR
* denies that the warming will cause severe consequences to human civilization; OR
* denies that humans can make significant reductions in warming and its effects by changing our behavior.

If the label annoys you, then I recommend that you stop being a denier.

 

So you're a denier then. Glad we cleared that up.

 

I have to ask, Hoos: who was it who lied to you about climate models, and why did you believe him?

Because if climate models really were as wrong as you think they are, you (or anyone else) should easily be able to pass this test: just pick out which of the eight lines is the real temperature and tell us why it's different from the rest. (The other seven are IPCC model runs.)

Really? So there was no economic expansion during cooling of the early 19th century? What an interesting re-write of the historical record you cling to.

So then you accept that half-measures are inadequate, and we need to do more? I'm proud of you, Hoosier. I think we're making progress!

 

LOL, only a brainwashed warmer could look at the graph and make that claim.

 

Since you think that graph is convincing, you should have no trouble answering those six questions about it that I posed. Because it's clear that lucas can't. C'mon, battle! Your denier pal is in trouble here! Lend him the benefit of your enormous brainpower, before he loses this debate!

 

No, I am a skeptic of "the sky is falling" crowd and the now failing predictions behind it.

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LOL, even the IPCC had to face up to the hiatus. Evidently you haven't yet.

 

Not at all. I just know enough about climate models, and enough about how much natural variability is in the system, and how that natural variability is correctly reflected by climate models, to understand that what you incorrectly call a "hiatus" is in fact par for the course when considering short runs of any noisy dataset. Which is something you apparently refuse to learn.

Now, how about taking that test?

 

I don't need to answer your questions since there are numerous papers presenting the failure of ALL the climate models to accurately predict the temperature. Google it and read.

Besides, its funny watching you warmers squirm and want to debate when you did not feel the need to explain the notorious "hockey stick" joke. For years all of us open minded people who wanted actual objective proof were instead just called names such as "deniers" and idiots and so on. You didn't feel the need to be educational then, and now I don't feel the need to waste my time educating a clearly closed minded "warmist". Google it and do some real reading (not your UN and political crap, but real papers) if you truly want to learn.

 

Riiiiiight. Evidence? We don't need no stinkin' evidence.

I've got a better idea. Cite them yourself, if you can. Of course you won't, because in fact there are no such studies. And don't even bother with anything that's not peer-reviewed, because denier blog postings don't cut the mustard with me, nor with anyone else who's knowledgeable in the field.

 

It is a waste of time, as you will note that they continue to return to AR4 reports to support their faith...

 

There is plenty of evidence, but you have to be willing to do a very simple action - use google. I understand its much easier to keep your eyes closed than to read teh papers and possibly challenge your bias and ideology, and maybe admit you are wrong.

If you do it yourself, there are benefits: you can't claim its "denier blog postings" since you will see the papers for yourself; and I wont waste my time trying to enlighten a person with a closed mind.

 

Guess that is why the climate models missed the natural variability. You don't "just know enough", you "know just enough" to prove you know little about climate models.