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Dikran Marsupial at 01:15 AM on 6 April 2012Murry Salby finds CO2 rise is natural
@tompinlb That the rise in atmospheric CO2 is purely anthropogenic is easily established with a high degree of certainty. In order to put an end to this common climate myth, I wrote a paper on the subject, read about it here. I sent a pre-print of the paper to Prof. Salby, but I didn't receive a reply. Sadly Prof. Salby is simply incorrect on this one, and I strongly suspect that the journal paper he referred to in hs talk may have been withdrawn. I would be happy to go through the mass balance argument with you, it really is surprisingly very simple. -
jzk at 21:19 PM on 5 April 2012James Hansen's Motivation
Daniel @14, Notice that Hansen begins his talk with "if we allow emissions to continue at a high rate..." Then he gets to talking about losing every species on Earth, and boiling the Oceans. Since all signs point to emissions rates increasing from where they are now (China and India), then according to Hansen these outcomes are real possibilities. This thread is entitled "James Hansen's motivation" and I was responding to a post that stated "I accept all that Hansen says." So how could my post possibly be off topic?Moderator Response:[DB] "So how could my post possibly be off topic?"
Again, reading my comment it is clear that I was referring to the individual factors Hansen discusses, like a methane/clathrate release. Those are best discussed further on individual threads devoted to them (Search function). Please desist in looking to quote-mine and take things out of context.
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Daniel Bailey at 21:14 PM on 5 April 2012James Hansen's Motivation
Jzk, the operative word Hansen uses is "can" (and please refer to the video in its entirety for context, not a solitary quote-mine). This is predicated on many variables also occurring, like first burning all the coal and then exploiting all the tar sands and shale oil extraction technologies and a methane/clathrate permafrost release. Note that the likelihood of this last is sharply confirmed here. Further discussion of those factors belongs on one of the many more relevant threads devoted to those topics, rather than this one. -
jzk at 20:58 PM on 5 April 2012James Hansen's Motivation
John @12, "I accept all that Hansen says." How about when he says that our Oceans will begin to boil? "you can get to a situation where, it just, the Oceans will begin to boil..." http://www.youtube.com/watch?feature=player_embedded&v=1uxfiuKB_R8#! @2:05. -
Lionel A at 20:37 PM on 5 April 2012Monckton Misleads California Lawmakers - Now It's Personal (Part 2)
some impressive pseudo-science babble here; - link CORRECTED I note that Motl has joined in too which demonstrates that even very clever people can be 'not even wrong'. -
John Russell at 19:44 PM on 5 April 2012Monckton Misleads California Lawmakers - Now It's Personal (Part 2)
Monckton appeared overnight with some impressive pseudo-science babble here; if anyone wants to take him on. As someone in the thread says: he's no time to answer Potholer but he's got time to comment there. -
John Russell at 18:22 PM on 5 April 2012Lindzen's London Illusions
Comment on the 5 scientists' critique on Carbon Brief, which seems to have attracted some major league contrarians in defence of Lindzen -- including Monckton. -
citizenschallenge at 15:21 PM on 5 April 2012Monckton Misleads California Lawmakers - Now It's Personal (Part 2)
boy that sounds like a dumb question. excuse me it's late, just that it's a new feature... I think. -
citizenschallenge at 15:19 PM on 5 April 2012Monckton Misleads California Lawmakers - Now It's Personal (Part 2)
Excellent Post. Considering that turkey lord has been causing me heartburn for a long time: http://citizenschallenge.blogspot.com/2010/08/unauthorized-sorting-of-lord-chris.html I appreciate Dana's point by point take-down. So much so that I've added it to my collection. Dana, John that "copy embed code" is a kick! Check out what I did with it: http://citizenschallenge.blogspot.com/2012/04/lord-chris-monckton-update-april-2012.html Hope you like it. cheers ~ ~ ~ Incidentally, where could learn more about that "copy embed code" thing? What it's about, what to do with? -
dana1981 at 14:07 PM on 5 April 2012Monckton Misleads California Lawmakers - Now It's Personal (Part 1)
Oh geez, I didn't notice the V&T estimate is $182 billion annually. What a freaking joke. I just can't believe anyone takes this nonsense seriously. But yes, as I recall Monckton did say $450 billion by 2020 (which is 8 years, not 10). -
scaddenp at 13:06 PM on 5 April 2012Murry Salby finds CO2 rise is natural
tompinlb - also are you aware that a very rough "rock weathering thermostat" is postulated operating in geological time scales. CO2 absorption by ocean is limited by Ca ion release. As temperatures go up, so does weathering rate, eventually pulling CO2 from atmosphere and cooling temperatures. More detail here. -
Bernard J. at 12:50 PM on 5 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
Bill and jmsully. Yes, amusing all 'round... It was revealing to see how Archibald dropped the ball once someone other than the cheer-squad started to ask some questions. I had plenty more to put to him, but the closing of the WWWT thread put paid to that, and Alex's post here (and, I anticipate, his next one in the series) has more than taken much of the wind from my sails. I am still curious though to have answers to my queries over there, so if anyone ever happens to come across Archibald, please ask him to address the specifics of the (at least) 20 questions. He appears to have made many methodological blunders quite separate from his mangling of physics, and if he intends to stand by that WWWT post as a 'credible' effort he must clarify the points that were raised. -
DSL at 12:43 PM on 5 April 2012Murry Salby finds CO2 rise is natural
tompinlb, did you read the article? Do you understand the mass balance argument? The natural world must achieve a rough equilibrium over geologic time scales, or else CO2 would disappear or supersaturate the atmosphere. The geologic record shows the development of the carbon equilibrium, and it has been in rough balance during most of the course of the latest interglacial. Suddenly, atmospheric carbon rockets upward. It's just coincident with massive human industrialization? Uhhhh . . . No. Humans have been dumping CO2 into the atmosphere faster than the historically developed (and developing) natural cycle can take it out. Eventually, there will be another point of rough equilibrium. Eventually. The isotope bit is just another line of evidence. -
Tom Curtis at 12:40 PM on 5 April 2012Murry Salby finds CO2 rise is natural
tompinlb @1: 1) CO2 concentrations over the holocene show little variation prior to the industrial era showing that the net natural CO2 flux is close to zero. Even the small 0.003 ppmv flux over the 7000 years prior to the industrial revolution is probably due to land use changes, partly from the desertification of the Sahara, but primarily due to human agriculture, particularly the cultivation of rice. The supposition that natural fluxes should increase 150 fold (conservatively estimated) by stange coincidence at exactly the time when humans started burning fossil fuels at a rate approximately double that which is required to explain the increase in CO2 in the atmosphere strains credulity, both in requiring human emissions to magically not effect atmospheric concentrations, and by requiring the vastly larger natural emissions from an undiscoverable source to magically coincide with the curiously ineffective human emissions.
So, to explain it for you, long term means over the period of the Holocene.
2) Not only do you require your magical natural source to have a peculiar sensitivity to the onset of industrialization, it must also be an aquatic organic source. Organic because only organic sources have the right C12/C13 ratio. Aquatic because only ocean sources and fossil fuels would deplete C14 ratios (as occurred prior to the onset of atmospheric nuclear explosions), and also because land vegetation is known to be increasing in mass. This depletion of organic matter in the ocean has to march in lock step with industrial emissions which, of course mysteriously continue to vanish without a trace.
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jmsully at 12:11 PM on 5 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
Bernard J., I did like the last comment in that thread: it must be the great and powerful PDO! -
tompinlb at 11:36 AM on 5 April 2012Murry Salby finds CO2 rise is natural
What is the basis for your statement that the natural flux of CO2 "balances out in the long term?" What do you mean by long term, and what evidence do you have for this assertion? In What the science says, you state that multiple lines of evidence make it very clear that the rise in co2 is due to human emissions. If you are basing this on analysis of c12/c13 isotope ratios! This is precisely one of the arguments that Salby takes apart. You do not address Salby's argument, but instead appear to appeal to authority. -
actually thoughtful at 10:38 AM on 5 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
MuonCounter - that is what I ask the deniers every day where is the cooling! Resounding silence is the answer. -
Tom Curtis at 10:34 AM on 5 April 2012Monckton Misleads California Lawmakers - Now It's Personal (Part 1)
dana1981 @24, being fair to Monckton he now claims that the figure he gives is for the losses over a decade, and that he obtained the figure by multiplying the annual losses a estimated by Varshney & Tootelian, 2012 by 2.5, which would indeed by a conservative assumption based on a flawed study. There is a reasonable question as to whether he made it clear that he was discussing decadal costs at the state legislature. More disturbing to my mind is his estimate of the benefits of the carbon tax. He claims to use a cost of 1.5% of GDP in 2100 for the harm from global warming. Purportedly this is a generous assumption, based on the Stern Report. In fact, however, the Stern Report estimates a cost of 5% of GDP, "each and every year, now and forever" which is reducible to 1% per annum by mitigation. So Monckton understates the costs of unmitigated climate change over the coming century by a factor of 240. A simple calculation shows that, on the simplifying assumption that California's carbon intensity equals the world average, and using the Stern Report figures, California's mitigation efforts will save it 800 billion in costs over 10 years. (I have also assumed that growth in GDP will be the inverse of the discount rate, ie, a discount rate equal to the pure rate of investment in California.) Finally, Monckton refers to California's "frankly Marxist legislature". Anybody who can refer to any legislature as Marxist shows that their words are so divorced from reality, whether by intent or insanity, as to be worthless. -
bill4344 at 10:22 AM on 5 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
Bernard J @11 That's a great exchange! I must say I think there's a very strong degree of causation here indeed; between your asking very detailed and uncomfortable questions, David Archibald's suddenly discovering he left the gas on, and dear old Anthony equally suddenly closing the thread. I think it's fair to say that the pristine beauty of certain ideas is best preserved from searing exposure to harsh realities... -
dana1981 at 09:22 AM on 5 April 2012Monckton Misleads California Lawmakers - Now It's Personal (Part 1)
To be clear here - I discussed why Monckton's economic analysis was wrong with Anthony Watts via email and offered him a version of the above post for WUWT. Not only did Watts decline to publish "the other side" (i.e. reality), but now he goes as far as to give Monckton a platform to further advertise his trumped-up nonsense economic alarmism, which Watts knows very well is wrong. In short, Watts publishes Monckton's nonsense, I inform Watts exactly why it's nonsense, and then Watts proceeds to publish a second Monckton post saying his nonsense was actually too conservative. So much for skepticism on WUWT. -
dana1981 at 09:15 AM on 5 April 2012Monckton Misleads California Lawmakers - Now It's Personal (Part 1)
Unbelievable - Monckton has doubled-down on this nonsense (on WUWT, naturally), claiming his $450 billion figure is an underestimate. His arguments, as usual, make no sense whatsoever. He basically argues that since he multiplied the trumped-up V&T figure by an arbitrary factor of 2.5 instead of an arbitrary factor of 10, he's being conservative! And WUWT slips another step further into lunacy. -
JMurphy at 05:43 AM on 5 April 2012New research from last week 13/2012
I'm sure these papers will appear here next week : How carbon dioxide melted the world Global data set shows that rising greenhouse-gas levels drove the end of the last ice age Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation -
heijdensejan at 04:43 AM on 5 April 2012Yes Happer and Spencer, Global Warming Continues
no it is still there but only on WUWT..... http://wattsupwiththat.com/2012/04/04/roy-spencers-uah-report-for-march/#comments -
Robert Murphy at 04:40 AM on 5 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
"And if all these natural factors lead to cooling, why is it still warming?" It's a Catch-22. That's the best there is. -
muoncounter at 04:09 AM on 5 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
Spoke too soon. If the frequency of volcanic eruptions increase during solar minima, the next step would be to drag in the cosmic ray increase during solar minima. Et voila: Ebisuzaki 2011: The strong negative correlation observed between the timing of silica-rich eruptions and solar activity can be explained by variations in cosmic-ray flux arising from solar modulation. ... such magma exists ... relatively close to the surface, within the penetration range of cosmic-ray muons (1–10 GeV). These muons can contribute to nucleation in supersaturated magma ... . This radiation-induced nucleation can lead to the pre-eruptive exsolution of H2O in the silica-rich magma. We note the possibility that the 1991 Mt. Pinatubo eruption was triggered by the same mechanism: an increase in cosmic-ray flux triggered by Typhoon Yunya, as a decrease in atmospheric pressure results in an increase in cosmic-ray flux. Staggering. Low point in the solar cycle has increased cosmic ray flux, which supposedly triggers explosive volcanic eruptions. Such eruptions lead to cooling. But low solar supposedly also leads to cooling. And typhoons trigger volcanoes (more cooling). If warming oceans lead to more vigorous typhoons, then does warming actually lead inexorably to cooling? And if all these natural factors lead to cooling, why is it still warming? -
muoncounter at 03:56 AM on 5 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
actually thoughtful, The solar-volcanic correlation is weak, but not random and it's been known for a while. From Stothers 1989: The historical record of large volcanic eruptions from 1500 to 1980, ... is subjected to detailed time series analysis. Two weak, but probably statistically significant, periodicities of ~11 and ~80 years are detected. Both cycles appear to correlate with well-known cycles of solar activity; the phasing is such that the frequency of volcanic eruptions increases (decreases) slightly around the times of solar minimum (maximum). Speculate about a causal relationship at your own peril! -
dana1981 at 01:21 AM on 5 April 2012Lindzen's London Illusions
Thanks John Russell, some very good points in that critique. -
Eric (skeptic) at 01:02 AM on 5 April 2012Yes Happer and Spencer, Global Warming Continues
Roy Spencer's March update is out with the unlabeled sinusoid overlay: http://www.drroyspencer.com/latest-global-temperatures/ I assume that means it is no longer entertainment but a prediction. What is interesting is that the initial downward part of the curve was mainly a blip from the two volcanic eruptions. Perhaps Dr Spencer is predicting more volcanic eruptions? -
Composer99 at 23:32 PM on 4 April 2012Monckton Misleads California Lawmakers - Now It's Personal (Part 2)
... OK, cliked "Submit" at the wrong time. Anyway, between all those, it's a shame anyone will still find his presentations at all convincing. -
Composer99 at 23:31 PM on 4 April 2012Monckton Misleads California Lawmakers - Now It's Personal (Part 2)
Between the various deconstructions of his nonsense by the Skeptical Science team, John Abraham, and Peter Hadfield (too bad Watts closed down their online debate, allowing Monckton to play the brave Sir Robin). -
Fran Barlow at 22:34 PM on 4 April 2012Monckton Misleads California Lawmakers - Now It's Personal (Part 2)
he has plotted them at 5:1 rather than 3:1. Get your rulers out and see for yourself!
Well he had to leave space for the text on the "credibility gap". That was much more important than minor matters such as having different years in different places, assuming that ceteris paribus applies and certainly the gradient in a trend. Semantic note: If something is "blinding" can it still be "obvious"? Surely if one is blinded, nothing is obvious, except perhaps that one is blinded. -
macoles at 21:53 PM on 4 April 2012Monckton Misleads California Lawmakers - Now It's Personal (Part 2)
Monckton's Credibility Gap (figure 1) is absolutely laughable. The lines are described as having 3K/century and 1K/century slopes, but he has plotted them at 5:1 rather than 3:1. Get your rulers out and see for yourself! So not only can he instantaneously time travel between 1950 and 2000 at the chart's origin, but it seams that he can warp the entire 2D space as well! -
John Russell at 21:40 PM on 4 April 2012Lindzen's London Illusions
A very detailed critique of Lindzen's Feb 22nd London lecture has now been published. The authors are B. Hoskins; J. Mitchel; T. Palmer; K. Shine & E. Wolff. It's well worth a read. The conclusion is interesting:"A pervasive aspect of RSL’s presentation was the conflation of uncertainty with ignorance; in his view, because we are uncertain about some aspect, we therefore know nothing about it and any estimate of it is mere guesswork. In this way we believe RSL does a disservice to the scientific method, which seeks to develop understanding in the face of inevitable uncertainties in our knowledge of the world in which we live. The scientific method has served society well for many hundreds of years, and we see no reason to doubt its validity for trying to quantify the risk of climate change and its impacts on society this century. On this basis we reassert that there is a substantial risk of human-induced climate change considerably larger than 1oC in global average this century and beyond. There is nothing in RSL’s talk to cast doubt on the existence of this risk. It is up to policy makers, not scientists, to decide whether governments should take concerted mitigating action to try to reduce this risk."
Let's hope all the attendees are sent a copy! -
John Russell at 20:16 PM on 4 April 2012Monckton Misleads California Lawmakers - Now It's Personal (Part 2)
@Doug H I think you're dead right about Monckton's rhetoric and his lawyerly debating ability. Winning an argument, for him, is about verbal skill and tactics -- not about seeking truth. One of Monckton's favourite phrases is, "...it's blindingly obvious...". I would suggest this sums up his approach. He looks at elements of climate science right up to the point where his limited understanding tells him what he wants to read and then stops. Sometimes he gets no further than the title of a paper or article, sometimes he has to dig deeper, but either way he finds a point which, superficially, appears to support his view and then he extracts and uses it. In that sense he's like a lawyer representing a client: cherry-picking the positive and avoiding reference to the negative. Science must seem very strange to him: I mean why would you consider aspects of the case -- sorry, 'subject' -- that don't support your argument? One thing I will say for him; his slides are highly coloured -- in more ways than one! -
Doug Hutcheson at 17:33 PM on 4 April 20122012 SkS Weekly Digest #13
I avidly read ([pedantry]or should that grammatically be 'read avidly'?[/pedantry]) every post and use the 'Comments' link to keep up to date with unfolding conversations. Therefore:- Do you subscribe to the daily email notice of newly posted articles on SkS? No
- Would you subscribe to a weekly email notice of newly posted articles if the option to do so was provided? No
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Doug Hutcheson at 16:40 PM on 4 April 2012Monckton Misleads California Lawmakers - Now It's Personal (Part 2)
Monckton believes he can convince
Monckton has a degree in Classics, according to wikipedia:Monckton was educated at Harrow School and Churchill College, Cambridge, where he received an BA/MA(Cambs.) in classics in 1974
Now, I have not had the benefit of an education in Classics, so perhaps I should be an obedient serf and not question my betters, but I am vaguely aware that a Classics degree may have touched upon the gentlemanly art of Rhetoric. In my twisted little mind, it would appear that Monckton has been trained to speak convincingly, in a lawyer-like manner, regardless of whether what he says exists in a factual vacuum. I can well believe that m'lud thinks he can convince uncritical people, because he plainly can. What I cannot decide is whether what he says bears any relationship to what he thinks. It is incredible to me that an apparently intelligent person, which I credit Monckton as being, could actually himself believe such a litany of misinformation. I am left to suppose that he knows better. -
Same Ordinary Fool at 14:00 PM on 4 April 2012Yes Happer and Spencer, Global Warming Continues
Here's another way of looking at some of the golden oldies in Happer's blogpost editorial...explicitly in terms of SkS's Skeptic Arguments. The Fixed Numbers numbering system in the Argument drop down box, is used because it is permanent. The other lists are in order of popularity, so their numbering will change over time. Fixed Numbers "Par" is the number of Happer's paragraph, followed by its first two words. Next comes a brief summary of Happer's statement. Followed by the Fixed Number, and the shortie description of the Skeptic Argument. Par 2 What is... For 10 years...........Fx7-1998 Par 3 The lack... Statistical significance..........Fx82-1995 Par 4 CO2 is... CO2 not a pollutant..........Fx42-pollutant Higher CO2 levels..........Fx45-pastco2 Plants grow better..........Fx120-plant Exaggerated effects..........Fx12-impacts Fossil fuel countries..........Fx177-expensive Par 5 The direct... Low sensitivity..........Fx30-sensitivity Positive feedback..........Fx-143-clouds Par 6 There has... Early warming..........Fx1-sun Natural causes..........Fx35-pre1940 Par 7 Frustrated by... Extreme weather..........Fx41-extreme Par 9 Large fluctuations... US cold weather..........Fx15-cold Par 13 It is... Computer models..........Fx5-model On its editorial pages, on the global warming issue, the Wall Street Journal plays a strange kind of favoritism towards the fossil fuel, and fossil fuel dependent, industries. While deceiving another constituency: all those who read the WSJ for long term investment advice. In this instance an atomic physicist writing as an authority on climate science declares that global temperatures have not increased much in the last 10 years. Yet we see from Foster and Rahmsdorf's graph in Fx7-1998 that, after removing the ENSO signal and the effects of solar and volcanic activity, that the global temperatures are actually still increasing relentlessly at the same rate as they have been since 1979. -
actually thoughtful at 13:49 PM on 4 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
Ari's latest post has a paper about the (apparently random) correlation between volcanic activity and solar cycles over the last century. Could the combination of major volcanic activity and solar minimum produce a causal relationship when both happen at the same time? -
dana1981 at 13:43 PM on 4 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
To be blunt for a moment, David Archibald is kind of a joke. I mean, the man tries to argue for solar warming by using temperature data from Hanover, New Hampshire. He's a notorious cherry picker. He's the author of possibly the worst climate paper ever. The only reason we have to continually debunk his nonsense is that the so-called "skeptics" take him seriously. I think Archibald is the posterboy for what's wrong with the global warming "skeptic" movement. -
Bernard J. at 13:38 PM on 4 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
Curiously, the second Archibald thread on WWWT was closed soon after mention of this thread was made on Digest 12's 'Coming soon' list. As far as I can fathom, the WWWT threads aren't usually closed so soon, so it appears that they were pre-empting some postings that might spoil the premise of the thread. Either that, or they thought that I might try to tweak Archibald's nose again as I already did at the bottom of the thread. If so, they were right - I was going to have another bash at his refusal to explain himself when I discovered that the door had been shut. -
actually thoughtful at 13:36 PM on 4 April 2012Weather records due to climate change: A game with loaded dice
I think the focus on 2 meters is, in a way, misleading. Storm surges will create Katrina like events in coastal cities long before the actual 2 meters is hit. Of course storm surges on top of 2 meters is so far beyond ugly that I can't honestly truly comprehend it. Sadly, on the current track, we shall indeed see. -
actually thoughtful at 13:07 PM on 4 April 2012New research from last week 13/2012
The Rypdal paper concerning random volcanic eruptions influence on our understanding of the solar cycle could use the SkS treatment. I suspect it won't much change our understanding of climate sensitivity, but it does challenge one important leg of our understanding (response to solar variation). -
John Hartz at 11:54 AM on 4 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
The results of the study detailed in this NSF news release bear directly on the issues being discussed on this comment thread. “Scientists Find Slow Subsidence of Earth's Crust Beneath the Mississippi Delta: But Gulf Coast sea-level rise rate five times higher now than in pre-industrial times.” To access this NSF news release, click here. -
scaddenp at 10:29 AM on 4 April 2012Stauning and Friis-Christensen on Solar Cycle Length and Global Warming
Looks to me like this paper might be relevant to claims of solar causality. -
Alex C at 06:16 AM on 4 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
@pauls at 03:20 AM on 4 April, 2012 Sorry, I understood your point when you said it first, my bad for not being clearer in my response. I think it would be good to consider pointing out as shown by the case study of the satellite record, but I don't know to what extent I can dismiss variation in past records as being due to tidal gauge variability. Perhaps though the methodology undertaken by Church and White 2011 undercuts that complaint though? @CTG at 05:14 AM on 4 April, 2012 Thanks for the suggestion, it's more than welcome. @dana1981 at 05:45 AM on 4 April, 2012 Thanks, but I already have the Church and White 2011 data in full, including their satellite data. I had obtained it a while back with the intent of using it in a later post. I cited the results from Jason and such given by the University of Colorado because it was the first satellite data source that came to mind when I wanted to use it for another previous purpose. -
dana1981 at 05:45 AM on 4 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
Alex, I've got the Church and White GMSL data mentioned by pauls @6 if you want to use it. -
CTG at 05:14 AM on 4 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
If you want to determine whether two cyclical looking trends do in fact have a causal relationship, another useful analysis is PCA. This will tell you whether there is synchronisation between the cycles, and which of the two is leading/lagging. I used this to analyse the 11-year cycle of Canadian lynx and Snowshoe hare populations, and determined that it was the hare population that was driving the cycle of the lynx population. I have a strong suspicion that PCA would show very clearly that there is a lack of synchronisation between GMSL and sunspots. -
pauls at 03:20 AM on 4 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
It's not much of an issue until you reach the twenty-first century (or, end of the twentieth) when we actually do have satellite altimetry, so we have to rely on tidal/coastal measurements beforehand. My point was that inferences concerning decadal global sea level trends aren't well-supported by reference to CMSL data since the two don't necessarily resolve to the same result over such a timescale. Church & White 2011 is an attempt to reconstruct a global sea level picture by calibrating tide gauge data to satellite alitimeters and then extrapolating that relationship back to the 19th Century. -
MA Rodger at 03:02 AM on 4 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
I always go cautious when Holgate 2007 is brought out. The 9 tidal gauge records it uses provide the data that "skeptics" like to use to say that sea level rise is decelerating, being lower on average in the second half of the twentieth century than in the first half. Holgate helpfully even does the arithmatic for them in the Abstract. -
Alex C at 02:38 AM on 4 April 2012Why David Archibald is wrong about solar cycles driving sea levels (Part 1)
@pauls at 02:11 AM on 4 April, 2012 That's a good point about coastal sea level trends v. global sea level, indeed Holgate 2007 used coastal gauges so perhaps my continued use of "GMSL trend" is misguided. It's not much of an issue until you reach the twenty-first century (or, end of the twentieth) when we actually do have satellite altimetry, so we have to rely on tidal/coastal measurements beforehand. I was planning on doing some discussion on satellite data in Part 2, but I will look into the paper you suggest and the issue of decadal variability in coastal measurements v. more stable satellite altimetry. I don't quite get the same values as you though with the satellite data - from U.Colorado's monthly data I calculated annual values and ran the same 10-year moving derivative that Holgate 2007 did, and I obtained a plot that peaked in ~2000 (1996-2005) at about 4mm/yr and dropped smoothly to ~2.3mm/yr in 2006 (2002-2011). Similar to an upside-down parabola. I suspect the end value is heavily influenced by the 2011 La Nina though.
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