[hrothgar]

Al_U_Card, on 2013-July-01, 05:40, said:

This is basically what has been argued for the last five years or so. Those "one-tree" effects were bogus and now it is finally being admitted by the authors as such. Since we know from the satellite record that global temps have been flat for almost 2 decades, where is the temperature/[CO2] effect that would lead us to need to do something....or anything?

Al is lying again

Quote

YAD061 is not the “most influential tree in the world”. It is a tree with high growth rate and some wide rings, and these contribute to the high values in the original Yamal chronology. But these occur in a period with elevated growth for many of the trees, not just that one tree. So its influence on the Yamal chronology – and on the conclusions drawn from the Yamal chronology – is rather limited. In the Briffa (2000) and Briffa et al. (2008) Yamal chronologies it has only a small influence. In our new chronology, its influence is imperceptible. For multi-proxy reconstructions that use the Yamal chronology along with other proxies, its influence is of course diluted further. And its influence on the climate change issue as a whole is negligible.

Let’s take a closer look at YAD061. In a few years since 1950, this tree had a very high index value of 7 or 8 (meaning these rings are 7 or 8 times wider than would be expected for rings of that age growing in average climate conditions). But this is nowhere near as rare as an 8-sigma value from a Normal distribution, because the TRW index values have strong positive skew (see Fig. PY03 in our SM5) favouring more frequent very high values. It is not the tree with the largest tree index value in the original Briffa (2000) and Briffa et al. (2008) datasets – tree L04551 has larger index values in the 1720s.

There is no clear justification for excluding YAD061, without also excluding other trees with high index values or indeed with low index values – and note the earlier discussion and concerns about post hoc data removal.

However, if you do remove core YAD061 and recreate the old Yamal chronology, the difference is quite limited: see this image. Of course the recent values are lower because you have deliberately searched for and removed the tree with the highest recent index values! But the difference is not enough to affect the main conclusions drawn from that work – clearly not the most influential tree in the world then.

For our new Yamal chronology the inclusion or exclusion of YAD061 makes no perceptible difference to the chronology (see this image; the red line is there, but virtually hidden under the black line). Our conclusions are compatible with those obtained with the old Yamal chronology. So how can YAD06 be the “most influential tree in the world”?!

There are two reasons why YAD061 has no effect on the new chronology and is not an outlier. (1) We have additional data. (2) We have improved tree-ring standardisation processes.

In our new chronology, 17 other trees have peak tree index values that exceed the peak value of YAD061, so it no longer even peaks at the 2nd highest, it peaks at the 18th highest. Of these 18 trees with the highest peak index values, 8 peak values occur in the 20th century and no more than 2 occur in any of the preceding 20 centuries. Clearly the 20th century is a period with enhanced tree-growth, so it is perhaps not surprising to find a tree like YAD061 during this period.

The improved standardisation includes a number of innovations. The key one here is that we now transform the tree index values to follow a normal distribution, which reduces the extremely high index values – e.g. YAD061 peaks around +3.5 standard deviations after this step, compared with the +8 index value before. Together with the expanded dataset, these are the reasons for the lack of sensitivity to inclusion/exclusion of core YAD061. See Fig. 2(a) of this blog to compare “old” and “new” chronologies.

McIntyre overstates the role of this single tree. His post title “YAD06 – the Most Influential Tree in the World” is hyperbole. Maybe he just wants to appear provocative and/or interesting. It has its downsides.

Not least causing others to also overstate things: Booker’s Telegraph piece: “On this astonishing tale, it is no exaggeration to say, could hang in considerable part the future shape of our civilisation.” Really? No exaggeration?

But it can also cause confusion. On 1 March 2010, Lord Nigel Lawson gave evidence to the UK House of Commons Science and Technology Committee that “for a long period before 1421 they relied on one single pine tree” (volume II, evidence EV4, page 9). We don’t know what he meant by this, nor what his source was, and maybe he didn’t really know either – but could he have read a blog post or an article talking about “the most influential tree in the world” and conflated that vague knowledge with questions about tree-ring divergence? It’s possible.

Tim Osborn, Tom Melvin

http://www.realclima...ate/#more-15500

[billw55]

Daniel1960, on 2013-July-01, 07:59, said:

Based on your source, 82% indicated that "human activity is a significant contributing factor in changing mean global temperature." By my calculations, that leaves 18% which do not. The debate is not whether humans have contributed to changing temperatures, but to what degree is this occurring. Since 1880, global temperatures have risen 0.8C (0.6C/century), and atmospheric CO2 levels have risen 36% (from 291 to 396 ppm). At the current rate of increase, CO2 will rise another 36% sometime in the 2090s. If the temperature rise was solely due to the CO2 increase, then we could expect another 0.8C temperature rise by then. Many scientists feel that other factors have contributed significantly to the observed temperature rise, and that a continued CO2 rise will result in a much lower temperature rise. Of course, there are those who feel that temperatures should have risen more than the observed 0.8C, and that a contined CO2 increase will lead to a much higher temperature rise. No survey has tried to measure these numbers, but those that believe that temperatures will accelerate are probably less than the 18% mentioned earlier. Many scientists feel that the 0.6C/century is a better indicator, as it incorporates all the factors influencing the temperature rise since 1880. Should this rate continue, we can expect another 0.5C temperature increase by 2100. There is another group that feels that the factors that contributed to the 20th century temperature rise will not continue through the 21st century. Should this occur, then the temperature rise will be even lower. There are even those who feel that natural factors contributed more than 50% to the observed temperature rise, and that they will be a negative contributor through 2100, resulting in a lower temperature than today. This is the climate change debate.

Interesting. What about another possibility - that natural factors (or if you prefer, factors other than CO₂) have been a net cooling influence over that period. And hence, that when (if) these factors subside, CO₂ driven warming may accelerate. I wonder if any scientists are taking such a position, or if any evidence suggests such a thing. You mention "probably less than 18%" expect acceleration - on what do you base that?

[Daniel1960]

billw55, on 2013-July-01, 08:35, said:

Interesting. What about another possibility - that natural factors (or if you prefer, factors other than CO₂) have been a net cooling influence over that period. And hence, that when (if) these factors subside, CO₂ driven warming may accelerate. I wonder if any scientists are taking such a position, or if any evidence suggests such a thing. You mention "probably less than 18%" expect acceleration - on what do you base that?

Bill, yes. Those are the ones who feel that temperatures should have risen more than the observed (that was included in my previous post). These are the people operating sites like RC and SKS, who feel that any day now, temperatures should start skyrocketing to compensate for the recent lack of warming, and the slowed 20th century warming trend. The last statement is based on personal experience with other scientists. There is no data to support or refute that statement (that I know of).

[Daniel1960]

Winstonm, on 2013-June-26, 12:42, said:

(emphasis added)


Just to clarify, I know that no such invitation came from BBO or its employees.

I finally had time to peruse the RC archives. The invitation came from one Richard Willey on Dec. 5, 2011 on the December, 2011 unforced variations thread (post #112), asking for contributors to the RC thread to stop by the bridgebase watercooler and respond to some of the posts. Apparently, he was looking for people to attack Al's posts, in an effort to "drown him under the weight of a bunch of replies."

http://www.realclima...nts_popup=10123

[hrothgar]

Daniel1960, on 2013-July-01, 09:59, said:

I finally had time to peruse the RC archives. The invitation came from one Richard Willey on Dec. 5, 2011 on the December, 2011 unforced variations thread (post #112), asking for contributors to the RC thread to stop by the bridgebase watercooler and respond to some of the posts. Apparently, he was looking for people to attack Al's posts, in an effort to "drown him under the weight of a bunch of replies."

http://www.realclima...nts_popup=10123

Guilty as charged...

I was hoping to get a much better class of trolls (or at least a lot more

Next time, I'll go try to piss off 4Chan...

[Winstonm]

Daniel1960, on 2013-July-01, 09:59, said:

I finally had time to peruse the RC archives. The invitation came from one Richard Willey on Dec. 5, 2011 on the December, 2011 unforced variations thread (post #112), asking for contributors to the RC thread to stop by the bridgebase watercooler and respond to some of the posts. Apparently, he was looking for people to attack Al's posts, in an effort to "drown him under the weight of a bunch of replies."

http://www.realclima...nts_popup=10123

I appreciate your taking time to look that up. Frankly, I can understand Richard's motivation. Probably the best thing to do is to totally ignore this thread and allow Al to play with himself.

Good advice - I think I will take it.

[billw55]

Winstonm, on 2013-July-01, 11:59, said:

I appreciate your taking time to look that up. Frankly, I can understand Richard's motivation. Probably the best thing to do is to totally ignore this thread and allow Al to play with himself.

Good advice - I think I will take it.

That might take it a bit far. There is an ignore user function you know.

[ArtK78]

Too late. We are now 1348 posts in.

[Al_U_Card]

Winstonm, on 2013-July-01, 11:59, said:

I appreciate your taking time to look that up. Frankly, I can understand Richard's motivation. Probably the best thing to do is to totally ignore this thread and allow Al to play with himself.

Good advice - I think I will take it.

Just establish a consensus and....no more worries....no more need to look at the data...just happily follow along and save the planet.

[Al_U_Card]

Daniel1960, on 2013-July-01, 09:59, said:

I finally had time to peruse the RC archives. The invitation came from one Richard Willey on Dec. 5, 2011 on the December, 2011 unforced variations thread (post #112), asking for contributors to the RC thread to stop by the bridgebase watercooler and respond to some of the posts. Apparently, he was looking for people to attack Al's posts, in an effort to "drown him under the weight of a bunch of replies."

http://www.realclima...nts_popup=10123

Google...hoists you on your own petard

Embarrassment....priceless

CAGW orthodoxy...pricey

[Al_U_Card]

When the Briffa reconstructions were taken to task for their reliance on certain trees without which there was no "unprecedented" warming, those criticisms were pooh-poohed by the Realclimate crowd with the type of hand-waving described above. The fact that those critiques were accurate and that Hantemirov and other co-authors had and still have numerous tree-ring results from well-documented sites in the Urals and Yamal, leads to the conclusion of cherry-picking to produce a hockey-stick. If not, then incompetence and/or laziness.

Interesting that the back-down is occurring now. Is it a withdrawal from the orthodoxy or is it smug confidence that the consensus continues to hold sway?

Where is that blade? Where is the crisis? Where are the data?

[ArtK78]

We are now 1352 posts in. What is the point of this exercise? Richard says black, Al says white. Black, white, black, white.

This argument (I won't call it a discussion anymore) is not going to solve anything. Neither side is going to convince the other. Eventually the world will come to an end or it won't, and the correct side can say "See?"

[Al_U_Card]

ArtK78, on 2013-July-02, 08:19, said:

We are now 1352 posts in. What is the point of this exercise? Richard says black, Al says white. Black, white, black, white.

This argument (I won't call it a discussion anymore) is not going to solve anything. Neither side is going to convince the other. Eventually the world will come to an end or it won't, and the correct side can say "See?"

From that perspective, I agree.

Positing an expected result requires proof and the appropriate analysis. If flaws are found in either, then redress is required as part of the scientific method. The purpose of this particular exercise is to demonstrate that no matter what errors are found or what contradicting information is presented, orthodoxy and a belief in CAGW is used to silence opposition and garner support.
The world is in a mess and we are most-often the cause of our own misery.
The weather and climate are so beyond our control (and even understanding according to the IPCC itself back in the first few reports (non-linear, chaotic system unable to be accurately modeled...) that only faith will allow for such an approach to be undertaken.
Climatism has become a religion.

[hrothgar]

Al_U_Card, on 2013-July-02, 08:28, said:

Positing an expected result requires proof and the appropriate analysis. If flaws are found in either, then redress is required as part of the scientific method. The purpose of this particular exercise is to demonstrate that no matter what errors are found or what contradicting information is presented, orthodoxy and a belief in CAGW is used to silence opposition and garner support.

I want to make sure that I understand this little exercise...

Lets assume that you post 1,000 critiques regarding global warming
950 of them are demonstrated to have little or no merit...
(This is a generous estimate regarding the contradictory drivel that you post)

Are you claiming that the remaining 50 examples are sufficient to discredit climate change?

[PassedOut]

Al_U_Card, on 2013-July-02, 08:28, said:

The world is in a mess and we are most-often the cause of our own misery.

Yes, the cause of this particular misery is mankind pumping billions of tons of heat-trapping gas into the atmosphere each year. Action, not faith, is the only way to reverse this.

Now it is not impossible that some hitherto unknown factor will mitigate the heat-trapping effects of what mankind is doing, but it takes a heap of faith to hang your hat upon that happening. I don't.

I'm much too conservative (and irreligious) to take that risk, especially since the solutions are beneficial -- and are inevitable over the long term -- anyway.

[Cascade]

hrothgar, on 2013-July-02, 08:55, said:

I want to make sure that I understand this little exercise...

Lets assume that you post 1,000 critiques regarding global warming
950 of them are demonstrated to have little or no merit...
(This is a generous estimate regarding the contradictory drivel that you post)

Are you claiming that the remaining 50 examples are sufficient to discredit climate change?

I would argue that it only takes one valid counter example to disprove a theory. Fifty therefore should be plenty.

[Daniel1960]

ArtK78, on 2013-July-02, 08:19, said:

We are now 1352 posts in. What is the point of this exercise? Richard says black, Al says white. Black, white, black, white.

This argument (I won't call it a discussion anymore) is not going to solve anything. Neither side is going to convince the other. Eventually the world will come to an end or it won't, and the correct side can say "See?"

While it is possible that either black or white will prevail in the end, I think you are overlooking a multiple of grays that could also be the correct side. Eventually, the world will come to an end. However, the amount of CO2 in the atmosphere will not be the cause. The Earth will go on, with or without us. The purpose of this thread is to discuss what the results of the increased CO2 may be, and what possible mitigations (if any) should be undertaken in response. Yes, there are those who will not be swayed from their position. That is not unique to this thread. Outside of this thread, there are many scientists who have moved significantly from their previous stances. The same may occur here.

[hrothgar]

Cascade, on 2013-July-02, 16:34, said:

I would argue that it only takes one valid counter example to disprove a theory. Fifty therefore should be plenty.

Interesting theory...

Mind relating this to Type I and Type II errors, hypothesis testing, and 95% confidence levels?

[nige1]

ArtK78, on 2013-July-02, 08:19, said:

We are now 1352 posts in. What is the point of this exercise? Richard says black, Al says white. Black, white, black, white. This argument (I won't call it a discussion anymore) is not going to solve anything. Neither side is going to convince the other. Eventually the world will come to an end or it won't, and the correct side can say "See?"

If the "scare-mongers" are right, few will survive to gloat.

You can learn from their new data and arguments. You do best to examine the evidence yourself and to try to reach your own conclusions rather than to accept naively the consensus of expert opinion To achieve this, you must usually over-simplify, which may detract from the validity of your conclusions; but history (e.g. phosphorus matches, lead tetra-ethyl, smoking) shows the alternative to be worse. Bridge controversies are another analogy Most young BBOers are scornful of the expert consensus of yesteryear; but simulations etc often confirm modern views.

[Cascade]

hrothgar, on 2013-July-02, 18:40, said:

Interesting theory...

Mind relating this to Type I and Type II errors, hypothesis testing, and 95% confidence levels?

A valid counter example is not the same as a statistical error.