Me on P. Thorne on Hansen et al.

1440598719541 I previously promised to read Hansen et al., and I finally have - well, at least skimmed. It hasn't really changed my opinions.

global CO2 emissions continue to increase... the threat posed by ice sheet instability and sea level rise

This is in accord with what I've said before, that the most obviously unambiguously bad physical consequence of GW is SLR (see What I think about global warming from 2010 for the rest, which I don't see any great reason to wish to update). So H focussing on it is understandable; but this leads to a regrettable tendency to need lots of SLR earlier than is obviously likely.

But I have read P. Thorne's review, and I find that very helpful. Eli also notes it, but appears to read it rather differently to me; I view it as substantially negative about the paper. Why?

In many senses the study should be uncontentious: this isn't a compliment. Why are you publishing boring stuff that people aren't going to disagree with? All the hosing stuff, for example, is passe.

The question really is how this sea level increase will occur: yes indeed; but does the paper manage to answer, or advance our knowledge of these questions? Not obviously.

during glacial to interglacial transitions, there are relatively short-lived events of rapid change... The question here is whether with an interglacial ice-sheet configuration as at present day such event types can occur... the assertion that we may lie close to... a tipping point... a period of large scale and rapid changes in sea-levels... To make this conclusion relies to an uncomfortable extent upon a causal chain... Each link in this chain is certainly plausible based upon the relatively scant evidence to hand, but is not by any stretch determinant... Given the length of the causal chain... it is far from certain that the results contended shall match what will happen in the real-world. This I think is the key problem; its the familiar long chain of connections which may be broken at any point.

The paper is of inordinate length: I see this as a warning sign of poor overall paper construction; as per previous, its like a brain-dump, which may be kinda interesting, but if H wants to publish such, well, he's got a blog and a mailing list. PT suggests editing to avoid repetition; my skim didn't see much of that but I would strongly argue for various sub-pieces to be hived off into separate papers; like the Bahamian sea level evidence.

there was a tendency in several places to editorialize. By that I mean that in places the paper tends to read somewhat more as a blog post or advocacy piece than a scholarly paper: see previous.

some simplified assumptions that the rate of ice sheet mass loss can be approximated by a doubling every n years... It is not in my mind sufficient to assert that recent behavior can be extrapolated forward more than a very finite time as a predictor for the future... some more physically based rationale would be warranted... I see a nice discussion in Section 7.3 but it does not directly address the realism of the model prescribed fluxes to the extent I would expect: this seems rather important.


* Robust global ocean cooling trend for the pre-industrial Common Era - McGregor et al.


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Thorne cannot show that the long chain won't happen, just that it is not very likely, which everyone knew. Given the reaction to the paper it is a bit disengenuous to say yeahyeah we know that tho.

Eli could see the editor telling Hansen et al to cut it down to 25 pages or so and make the areas of speculation clear.

By Eli Rabett (not verified) on 31 Aug 2015 #permalink

OTOP, Eli sees you are scouting out places to hide out when the sea level burps.

By Eli Rabett (not verified) on 31 Aug 2015 #permalink

I tell the youngsters in my World Climates class that SLR is the one consequence of climate change to really worry about. So you agree with me, which is always wise.

As for Hansen's article - just reading the abstract makes my head hurt. It jumps from one topic to another too fast for me to follow. Is the rest of the paper like that?

[I can't really tell; I didn't read it very carefully. For example, I can't tell why they did the hosing experiments. These seem perfectly standard, so why not just read someone else's paper? -W]

By Raymond Arritt (not verified) on 31 Aug 2015 #permalink

Yes, Thorne's review is quite clearly negative, in all the right ways.

By Nick Barnes (not verified) on 01 Sep 2015 #permalink

"it's the familiar long chain of connections which may be broken at any point."

If the likelihood the chain not breaking exceeds X percent, that might be an encouragement to do something beyond all our other reasons. I don't know what X is, but I'd guess that it's around 0.5%

By Brian Schmidt (not verified) on 01 Sep 2015 #permalink

Well, not as negative as this one

This manuscript is gibberish and should be rejected.

There is no conceivable revision that could render it publishable.

It repeats and builds on a foundation of gibberish that the author has previously managed to get published in fourth tier journals such as E&E with no effective peer review, and builds on it with more gibberish. I am not going to take time to give a complete account of all the nonsense in this paper, but will only confine myself to a few key points. . . .

["Miskolczi continues to shop this work around, presumably in the hope of eventually finding reviewers gullible or lazy enough to let it through. I do not really know the author's motivations, but this is certainly a shameless abuse of the peer review system..." - lovely. How did you find it? -W]

By Eli Rabett (not verified) on 01 Sep 2015 #permalink

Eemian Superstorms or regular old Atlantic Ocean tsunamis?

Revision of the Portuguese catalog of tsunamis

The Grand Banks landslide-generated tsunami of November 18, 1929: preliminary analysis and numerical modeling

The Transoceanic 1755 Lisbon Tsunami in Martinique…

Far field tsunami simulations of the 1755 Lisbon earthquake: Implications for tsunami hazard to the U.S. East Coast and the Caribbean………

Bonus question: Is it easier to flip a fat ended flat rock than to lift a fat ended flat rock? (Hint, Sad fat ended flat rock forms the top of a recurved sedimentary rock shore face, sort of just like what one see's today, dynamic wave overpressure fractures the underside of said recurved sedimentary rock shore face ... )

By Everett F Sargent (not verified) on 02 Sep 2015 #permalink

Well, lookie here:

Boulder deposition during major tsunami events…

"We use numerical hydrodynamic modeling of tsunami
(and storm) waves to test the observational data on boulder dimensions (density, size, distribution) on the most likely processes of sediment deposition. This work demonstrates the effectiveness of the study of boulder deposits in tsunami reconstruction."

Holy Rollers, Batman, somebody took a conjecture, turned it into an actual testable hypothesis, via hydrodynamic modelling no less. Why didn't I think of that? Oh wait, I did.

By Everett F Sargent (not verified) on 02 Sep 2015 #permalink

Albeit I, have a dog in the albedo tipping point fight-- brightening arctic water to retard the meltdown of adjecent ice I find it hard to enthuse over Hansen's dystopic logic.

So many variables are in play that the precautionary principle becomes self-referential if you impute worst-case values to all of them in its name.

"Miskolczi continues to shop this work around, presumably in the hope of eventually finding reviewers gullible or lazy enough to let it through."

Oops ... pay to play potty 'peer' published ...


It sort of got published in China!

JC gives it two thumbs up though

"So given that I have spent about 40 minutes on this blog post, I am leaving this topic open as a discussion thread, and not contributing much myself."

" ... not contributing much myself ... "

She can say that one again and again and ...

By Everett F Sargent (not verified) on 02 Sep 2015 #permalink

Oops again ...

In the "Google Scholar is your friend" department we have ...,2…

Anthropogenic and Natural Forcings as Functions of Emission Time

Same urinal no less.

Authored by one 'Nabil Swedan' who just happens to have posted like 10 comments in ONE thread in the discussion of Hansen, et. al.

Which the EC has now closed ...

"The editor decided to not accept further comments to this thread. Scientifically sound comments on other topics are possible until the end of the discussion phase."

Seriously, you can't make this stuff up ...

By Everett F Sargent (not verified) on 02 Sep 2015 #permalink

Eli slums over at Judy's on occassion. There are still some Mis alcolytes there.

By Eli Rabett (not verified) on 03 Sep 2015 #permalink