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Comment on The Forest 2006 climate sensitivity study and misprocessing of data – an update by Peter Lang

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Nic Lewis, Thank you for this update and all the work you have done over the past few years to understand ECS and communicate your findings to lay people like us here and on Climate Audit and Bishop Hill. From my perspective ECS is one of the four most critical inputs for cost-benefit analysis and robust analysis of policies to deal with AGW. One message I take from your work is how important it is to use the correct statistical methods. This, of course, is another example of what was found with long history of the ‘Hockey Stick’, Steve McIntyre’s excellent discovery and the many enquiries. Nic, or someone knowledgeable, could you please clarify for me? Is the PDF, of F06’s <i>estimates<i> of ECS, or of the real world ECS? To try to clarify what I am asking, the title for the horizontal axis on the first figure says “<i>Equilibrium Climate Sensitivity Seq – Global mean Temperature rise for doubled CO2</i>. However, I think this title should be “<i>PDF of F06’s estimates of equilibrium climate sensitivity</i>” Is my understanding I correct?

Comment on Historic Variations in Arctic sea ice. Part II: 1920-1950 by manacker

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Tony B

I know you have done quite a bit of research on this topic, but a lot has been written about Northwest Passage crossings. Here is a sample.

http://geography.about.com/od/specificplacesofinterest/a/northwestpassag.htm

in 1906 Roald Amundsen from Norway successfully spent three years traversing the Northwest Passage in an ice-fortified ship.

Amundsen sailed the three-masted schooner Maud in his second crossing of the passage in 1924-1926.

In 1944 a Royal Canadian Mounted Police sergeant made the first single-season crossing of the Northwest Passage. Since then, many ships have made the trip through the Northwest Passage

From another source:
http://www.norwegianblue.co.uk/history.htm

Nobody was to complete this journey again until 1942 when the Canadian ship ‘St Roch’ and its captain Henry Larsen made the second complete transit and the first from West to East. Larsen didn’t just call it a day there though, he then turned round and went back through the other way!

Another source tells us:
http://geology.com/articles/northwest-passage.shtml

In 1957, three United States Coast Guard Cutters, Storis, Bramble and SPAR became the first ships to cross the Northwest Passage along a deep draft route. They covered the 4,500 miles of semi-charted water in 64 days.

The first ship capable of carrying significant cargo to traverse the Passage was the SS Manhattan, a specially reinforced supertanker, in 1969. It was accompanied by the John A Macdonald, a Canadian icebreaker. This trip was taken to test the Northwest Passage as an alternative to building the Alaska Pipeline. At that time it was determined that the Northwest Passage was not economical and the Alaska Pipeline was built.

Yet another source:
http://www.norwegianblue.co.uk/history.htm

In 1977 the Belgian sailor Willy de Roos and his steel ketch ‘Willywaw’ became the 3rd yacht to go through, largely single handed.

Recent development:

http://people.hofstra.edu/geotrans/eng/ch1en/conc1en/polarroutes.html

In 2007 the Northwest Passage was open during the summer months for the first time in recent history, but it remains to be seen how stable this opening is. In 2009, two German ships, Beluga Fraternity and Beluga Foresight, completed the first commercial journey across the Northern Sea Route (or Northeast Passage) linking Busan to Rotterdam with several stopovers.

No doubt, modern navigation technologies and systems have made sailing the NW passage much easier than it was earlier. And receding late-summer sea ice could also present a new opportunity. But predictions for the future remain cautious.

The consideration of arctic routes for commercial navigation purposes remains a very speculative endeavor, mainly for three main reasons:
• First, it is uncertain to what extent the receding perennial ice cover is a confirmed trend or simply part of a long term climatic cycle. Even if the Artic routes became regularly open during the summer, the medium terms underlines that that Arctic would still remain closed to commercial navigation during the winter months. As of 2010, the ice free conditions of most Arctic shipping routes were only about 30 days. Since maritime shipping companies are looking for regular and consistent services, this seasonality has limited commercial appeal.
• Second, there is very limited economic activity around the Arctic Circle, implying that shipping services crossing the Arctic have almost no opportunity to drop and pick-up cargo as they pass through. Thus, unlike other long distance commercial shipping routes there is limited revenue generation potential for shipping lines along the Arctic route, which forbids the emergence of transshipment hubs. This value proposition could improve if resources (oil and mining) around the Arctic are extracted in greater quantities, which would favor bulk shipping.
• The Arctic remains a frontier in terms of weather forecast, charting and building a navigation system, implying uncertainties and unreliability for navigation. This implies that substantial efforts have to be made to insure that navigation can take in place in a safe manner along well defined navigation routes.

In view of all of the above maritime shipping companies are not yet considering seriously the commercial potential of the Arctic as a navigation shortcut. Still, the rise in bunker fuel prices and slow steaming practices can be considered incentives for the development of niche services that could use the Arctic as a shortcut between major markets of the northern hemisphere. By doing so, shipping services would have the option to mitigate the distance advantage of the shorter Arctic routes with the option of slower speeds and their fuel consumption benefits.

So it looks like it will still be a while before the NW Passage becomes the preferred route for summer crossing

But, if and when it eventually does, assuming the current shrinking of late-summer Arctic sea ices continues, it could end up being a net positive development.

Max

Comment on Historic Variations in Arctic sea ice. Part II: 1920-1950 by Manfred

Comment on Historic Variations in Arctic sea ice. Part II: 1920-1950 by manacker

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Hey, Beth, keep “tellin’ it like it is” and leave the careful caveats and historic finesses to Tony, the historian.

Another serf

Comment on The Forest 2006 climate sensitivity study and misprocessing of data – an update by Peter Lang

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[repost with corrected formatting, sorry]

Nic Lewis,

Thank you for this update and all the work you have done over the past few years to understand ECS and communicate your findings to lay people like us here and on Climate Audit and Bishop Hill. From my perspective ECS is one of the four most critical inputs for cost-benefit analysis and robust analysis of policies to deal with AGW.

One message I take from your work is how important it is to use the correct statistical methods. This, of course, is another example of what was found with long history of the ‘Hockey Stick’, Steve McIntyre’s excellent discovery and the many enquiries.

Could you or someone knowledgeable please clarify something for me someone?

Is the PDF, e.g. in Figure 1, the PDF of F06’s estimates of ECS, or the PDF of the real world ECS?

The title for the horizontal axis on the first figure says “Equilibrium Climate Sensitivity Seq – Global mean Temperature rise for doubled CO2

However, I think this title should be “PDF of F06’s estimates of equilibrium climate sensitivity

Is my understanding I correct?

Comment on The Forest 2006 climate sensitivity study and misprocessing of data – an update by Peter Lang

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I asked on a previous thread what is the effect of a reduction in our estimate of ECS from 3K to 2K on the break-even date (i.e. when AGW damages exceed the benefits)? According to Bjorn Lomborg (from Nordhaus, Tol and others), the estimated break-even date is about 2070. That is based on the IPCC AR4 estimates of climate sensitivity and inputs used for estimating the damage function (p23 here: http://nordhaus.econ.yale.edu/Accom_Notes_100507.pdf).

If ECS is 2K instead of 3K, when will break-even occur? (e.g. 2120?).

Comment on Historic Variations in Arctic sea ice. Part II: 1920-1950 by manacker

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Fan

Regarding the doubtful accuracy of Soviet meteorological records.

It probably depends a lot on the extenuating circumstances how reliable these might be.

It the case of the temperature records, which I cited, there was a clear incentive to report colder temperatures.

In cases where the Soviet leaders felt it would be advantageous to their political cause to fudge the data, I’m sure this was done (and there may be several instances, including the example you cited, where this was the case).

And, of course, there was probably a lot of sloppiness (it seems endemic in totalitarian regimes).

But I do not believe that there was a systematic fudging of data in the old Soviet Union just to fudge the data.

Do you?

Max

Comment on The Forest 2006 climate sensitivity study and misprocessing of data – an update by A fan of *MORE* discourse


Comment on The Forest 2006 climate sensitivity study and misprocessing of data – an update by Steven Mosher

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” he has publicized technical results before seeking review.”

actually Nic has a paper that is in press on this topic. AR5 discusses this paper. However, they did not adjudicate the matter between Forest06 and Nic’s new paper. In their text they suggest that the discrepancy might be due to mis processing data. The subject is already in the air. Nic has an absolute right to discuss his approach and findings in public. Especially since behind the walls Ar5 is pressing forward.

Comment on Historic Variations in Arctic sea ice. Part II: 1920-1950 by Beth Cooper

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Thanks fer yer kind serf message, Max.)
The other serf.

Comment on The Forest 2006 climate sensitivity study and misprocessing of data – an update by Steven Mosher

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Jim: you’ve been supplied the links many times.

Start with Ar4. start with the bibliography of the papers on sensitivity.

For temperature measurements ( Sensitivity = delta C/Delta Watts)
you can see:

1. had crut
2. Giss
3. Berkeley Earth
4. UAH or RSS

or you can go back further in time with measurement made by proxy.
( big uncertainy, but you know how to handle that right?)

For forcings, since they are documented in several places I’ll suggest
http://www.pik-potsdam.de/~mmalte/rcps/

all in one spot

http://www.pik-potsdam.de/~mmalte/rcps/data/20THCENTURY_MIDYEAR_RADFORCING.xls

To measure speed you measure distance and time.
To measure sensitivity you measure temperature and forcing.

How many times do you want the instructions on where to find this.

You calculate sensitivity by looking at the CHANGE in temperature
per CHANGE in forcing.

You’ve been given the links to temperature.
You’ve been given the change in forcings.
calculate… or read the literature

Here is a good one.

And keep this in mind. We can measure things without doing experiments.

with the R code

https://skydrive.live.com/?cid=0dbeb27d6a80282b&id=DBEB27D6A80282B%21108

Comment on The Forest 2006 climate sensitivity study and misprocessing of data – an update by manacker

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Peter Lang

“Break-even date” is a nebulous concept, as far as I am concerned.

But let’s look at the impact of replacing the previously assumed 2xCO2 ECS estimate of 3C (IPCC AR4) with a revised estimate of 2C.

IPCC AR4 has several “scenarios and storylines” for future GHG concentrations and projected warming.

Let’s take an average of all cases (B1, A1T, B2, A1B, A2 and A1F1).

These have CO2 equivalent rising to an average of around 698 ppmv by 2100 and around 570 ppmv by 2070.

So, if the “break-even” point was 2070 with the old ECS estimate of 3C, this means breakeven occurs at:

3C* ln(570/392) / ln(2) = 1.6C warming above today’s temperature

So until we reach this level of warming, the net result of AGW is beneficial (as I understand your qpremise).

Let’s ASS-U-ME that this is the case and that at warming exceeding 1.62C above today’s temperature we will start to see a net negative impact with added warming.

So when would we reach 1.62C added warming with an ECS of only 2C?

This would occur at 690 ppmv concentration:

2C*ln(690/392) / ln(2) = 1.62C warming above today’s temperature.

Using the average CO2 concentration of the IPCC AR4 “scenarios and storylines” cited above, this would occur in year 2098.

So we have moved the ASS-U-MEd “breakeven point” from 2070 to 2098.

Which would mean that essentially throughout this century AGW would have a net beneficial effect

Max

PS Let’s see if anyone wants to challenge this calculation.

Comment on The Forest 2006 climate sensitivity study and misprocessing of data – an update by A fan of *MORE* discourse

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The following are two distinct statements, eh Steven Mosher?

• “Nic Lewis has an absolute right”, versus

• “Nic Lewis did absolutely right.”

The “absolutely right” path for Nicholas Lewis (collegially speaking) would have been to solicit from Dr. Forest, before going public with his criticisms. Especially since Dr. Forest’s behavior to Nicholas Lewis has been so scrupulously civil and respectful.

Ain’t *this* the path of plain common sense and collegial good manners, Steven Mosher?

\scriptstyle\rule[2.25ex]{0.01pt}{0.01pt}\,\boldsymbol{\overset{\scriptstyle\circ\wedge\circ}{\smile}\,\heartsuit\,{\displaystyle\text{\bfseries!!!}}\,\heartsuit\,\overset{\scriptstyle\circ\wedge\circ}{\smile}}\ \rule[-0.25ex]{0.01pt}{0.01pt}

Comment on The Forest 2006 climate sensitivity study and misprocessing of data – an update by David Young

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Fanny, Steve Mosher is right. This is a public matter. The paper being discussed is in a journal. Your fanny covering attempt to suggest that secrecy is called for is just anti-science. Forest is free to come here and discuss it calmly. Nic is very adult and doesn’t need you to tell him about ethics or scientific etiquit.

Comment on The Forest 2006 climate sensitivity study and misprocessing of data – an update by Jim Cripwell

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Steven, you writre “You’ve been given the links to temperature.
You’ve been given the change in forcings.
calculate… or read the literature”

What I have NOT been given, is the proof that the change in temperature has been caused by the change in forcing, or whatever. That is the issue which you studiously will not address. Until you address that issue, everything you have written is a complete and utter load of garbage.

Where is the proof that the change in forcing has actually caused the change in temperature?


Comment on The Forest 2006 climate sensitivity study and misprocessing of data – an update by A fan of *MORE* discourse

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David Young, please reflect more deeply on the dynamic of scientific discourse. What Anthony Watts did wrong chiefly was to waste people’s time with defective research.

That’s why the “absolutely right” path for Nicholas Lewis (collegially speaking) would have been to solicit critical input from Dr. Forest, before going public with his criticisms. Because as Anthony Watts and the general public both learned (the hard way) there’s more to peer review (far more!) than formal peer review!

Sometimes the criticism you receive … from showing your work to your peers and humbly asking for criticism … is just plain correct! Ain’t *this* the path of plain common sense, *and* good manners, *and* better science, David Young?

\scriptstyle\rule[2.25ex]{0.01pt}{0.01pt}\,\boldsymbol{\overset{\scriptstyle\circ\wedge\circ}{\smile}\,\heartsuit\,{\displaystyle\text{\bfseries!!!}}\,\heartsuit\,\overset{\scriptstyle\circ\wedge\circ}{\smile}}\ \rule[-0.25ex]{0.01pt}{0.01pt}

Comment on Historic Variations in Arctic sea ice. Part II: 1920-1950 by Steven Mosher

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The most pronounced warming phase in our reconstruction
occurred between 1900 and 1940, which is clearly
seen in the measured meteorological records as well. In the
instrumental record, positive SAT anomalies were largest
in the Arctic Atlantic region during this period (Wood and
Overland 2010). This early twentieth-century warming
(ETCW) has been subject to many studies, yet its reasons
still defies full explanation. Natural and anthropogenic
(land-use, aerosols) forcings are believed to have contributed
to the ETCW (e.g., Delworth and Knutson 2000;
Bengtsson et al. 2004; Bro¨nnimann 2009). According to
Chylek et al. (2009), the Arctic warming from 1900 to
1940 proceeded at a significantly faster rate than the
warming during the more recent decades and was highly
correlated with the Atlantic Multi-decadal Oscillation
(AMO) suggesting that the Arctic temperature variability is
highly linked to the Atlantic Ocean thermohaline circulation
at various temporal scales.

Comment on The Forest 2006 climate sensitivity study and misprocessing of data – an update by Beth Cooper

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lolwot,@7.51pm re CERN, admits complexity in climate,
‘things that cannot be simulated.’ Say, lolwot, do yer not
have similar reservations about climate models, you know,
… by climate modellers in cloud towers whiling away the
tenured hours? Hmmm, what’s the difference between
‘ whiles’ and ‘ wiles?’ )

A serf.

Comment on Historic Variations in Arctic sea ice. Part II: 1920-1950 by manacker

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Lucy Skywalker

The medieval Greenland farm buried in the permafrost is indeed physical evidence providing confirmation that temperature was warmer “in the Arctic” (since Greenland is “in the Arctic” and it was obviously warmer then than now).

By itself it may not be evidence that temperature was warmer “across the entire Arctic” (as R. Gates states) or “across the Northern Hemisphere” (as is generally accepted since the analysis by Hubert Lamb).

But there are other bits of evidence.

And I agree fully with you that Tony’s approach will give us much more valuable data than relying on paleo proxy reconstructions alone – and using both approaches TOGETHER might even give us a better idea of our past climate.

But the paleo guys do not like historical evidence, which they write off as “anecdotal”.

Too bad.

Max

Comment on Historic Variations in Arctic sea ice. Part II: 1920-1950 by manacker

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Famous quotations of yesteryear:

“I am not a crook.”

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