Let's play Hockey

[ee-tom]

THREAD RULES. BE POLITE. NO AD HOMS (trying to prove argument by attacking the integrity of the arguer. It is fine to show specific instances of incompetence etc if directly relevant). KEEP TO THE TOPIC.

Lensman challenged me on another thread, saying that it was obvious Mann suppressed information with his infamous "hockey stick graph"

The argument for this is summarised by Lensman as follows:

 

Lensman said:

Here is a temperature graph of the past 1000 years published in 1990. Was it from some global warming skeptic blog? No, it's from the IPCC's own official executive summary for that year:

 

 

 

 

 

 

 

 

 

And here is the infamous "hockey stick" graph which pretends to show the temperatures for the same period, the past 1000 years:

 

 

 

 

 

 

 

 

 

 

 

 

The suppression by Mann et al of the widespread and well-documented evidence for the Little Ice Age cannot be disputed. The evidence of the Medieval Warm Period is less well established-- current (hopefully better) data would show the maximum temperature lower than current temperatures-- but there is no legitimate reason for Mann deliberately omitting the data for the LIA.

If you deny there is clear bias shown here, if you deny that the "hockey stick" graph has been made the centerpiece of the alarmist AGW argument, and if you deny that this is a deliberate suppression of evidence of natural climate change by so-called "consensus" climate science, then it's pretty obvious just who is in denial here, Tom.

As they say: "You are entitled to your own opinion. You are not entitled to your own facts."

So let us get to the bottom of this. There are really four separate questions:

(1) Are the graphs Lensman posts, which appear to show strong disagreement, what they seem? There are lies, damned lies, statistic, and AGW-related graphs. Thre latter being the easiest to distort. So let us look at lensman's data and see what happens.

(2) is the overall Hockey Stick temperature shape correct? In other words, given the best information now, do we have a grpah looking like that?

(3) Was Mann guilty of deliberate distortion of facts etc?

(4) Is this graph the centrepiece of the AGW argumen?

I suggest we deal with (1) and (2) first. When the science on these to questions is settled we should be in a good position to tackle (3). I propose we ignore (4). It is very political - the hockey stick is a very powerful popular illustration -  but no single graph is much use at conveying the whole scientific picture. Since i am interested in the science much more than how it is presented (TP I think sometimes worries I may be giving ammunition to "the other side") I'll ignore the politics. As far as i am concerned, looking at the science, there are not two sides. Of course, in the politics there are, and internet debates which do not drill down into the detail of the science and shake it till the truth emerges can similarly polarise. I'm hoping we can avoid that sort of thing here.

Now I could post a rebuttal with a whole load of graphs, and referenced peer-reviewed papers as sources which shows in answer to (20 that Mann's Hockey Stick looks fine.

But that will not work, and would be unfair. It is necessary to post precise arguments with precise counter-arguments.

Prima facie the graph lensman posts looks damning. But is it? One thing that worries me is that it has no temperature scale. Another that we do not know over what scale it is averaged. Obviously the last bit of the hockey stick is very sharp, so if we average over 100 years or so we will suppress it.

I'll do some investigation. Perhaps Lensman can do the same.

[Parallel]

No sign of the sea temperature warming either.  I wonder where all the CO2 heat is hiding.

[WalksOnDirt]

Parallel said:

I wonder where all the CO2 heat is hiding.

ome of it melted ice, some of it warmed the deeper ocean, and some of it has probably been offset by increased aerosols from China and India.

[Parallel]

You're really not paying attention are you.

Have you seen the amount of ice now?  Thought about how little difference that makes?

Warming deeper ocean by being cooler on top?  Surely you can do better that?

You must have missed the recent papers showing that aerosols don't actually cool things so much.
http://www.latimes.com/news/science/sciencenow/la-climate-cooling-o...

WalksOnDirt said:

Parallel said:

I wonder where all the CO2 heat is hiding.

ome of it melted ice, some of it warmed the deeper ocean, and some of it has probably been offset by increased aerosols from China and India.

[WalksOnDirt]

Parallel said:

Have you seen the amount of ice now?

It's melting.  This is just the Arctic sea ice, but it is all slowly melting.

Thought about how little difference that makes?

I don't really know, and I have seen no estimates.  It does offset some of the warming, though.

Warming deeper ocean by being cooler on top?  Surely you can do better that?

One form of heat transfer in the ocean is convection.  The rate of transfer to the deep ocean will vary.  When the transfer is more rapid the surface will be cooler, when it is slower the surface will be warmer.  This is the opposite of what you would see from conduction, but that is a minor method of oceanic heat transfer. 

You must have missed the recent papers showing that aerosols don't actually cool things so much.
http://www.latimes.com/news/science/sciencenow/la-climate-cooling-o...

 

That is just one paper.  It may or may not be correct.  In any case, aerosols still cool and they have been rising lately.

[Parallel]

This paper by SteveF Estimating the Underlying Trend in Recent Warming seems better than most. http://rankexploits.com/musings/2013/estimating-the-underlying-tren...

"Warming has not stopped, but it has slowed considerably. This analysis can’t prove the cause for that change in rate of warming, but any suggestion that solar cycles, volcanic aerosols, and ENSO are completely responsible for the recent slower warming rate is not supported by the data. Some may suggest long term cyclical variation in the secular warming rate has caused the recent slow-down, but this analysis can’t support or refute that suggestion.

,,,,it is tempting to infer very low climate sensitivity from the regression constants for volcanic aerosols and solar cycle forcing (these constants have units of degrees/watt/M^2, and the values correspond to a climate sensitivity of a little less than 1C per doubling of CO2). This temptation should be resisted, because the model does not consider the influence of (slower) heat transfer between the surface and deeper ocean. In other words, the calculated impact of solar and volcanic forcings would be larger (implying somewhat higher climate sensitivity) if a better model of heat uptake/release to/from the ocean were used."

I currently think the evidence points to a climate sensitivity in the range i - 2 C and the IPCC has run out of gas, still suggesting it is 3 C.

[Parallel]

An Engineer’s Take on Climate Change #2
Posted on June 14, 2013    by Guest Blogger

Guest essay by Ronald D. Voisin

High Atmospheric CO2 is Good for All Life on Earth

At an atmospheric concentration of 380ppm and higher the limited long-wave spectral absorption of CO2 is essentially saturated. Consequently, yet more atmospheric CO2 becomes vanishingly less relevant to a greenhouse effect (if at all). And when more atmospheric water vapor is objectively evaluated its net-effect is found to be a negative-feedback rather than a positive one (in direct contradiction to the presumption of the Models). However, enhanced atmospheric CO2 clearly stimulates the proliferation of all forms of life. You might best call it Vitamin C…(O2).

http://wattsupwiththat.com/2013/06/14/an-engineers-take-on-climate-...

[Parallel]

A most devastating analysis of the IPCC's position with computer generated climate models.  We have 73 models, so by definition 72 must be wrong.  Does that give you great confidence in the 73rd one?

R G Brown is a physicyst at Duke U.  He demonstrates conclusively, that the numbers used by IPCC are literally meaningless.  I doubt that ee-tom will even try rebutting this one.

On the meaning of ensemble means.
http://bishophill.squarespace.com/blog/2013/6/14/on-the-meaning-of-...