A rising tide of controversy
I've not followed the sea level rise story closely, but my interest was piqued by Morner's lecture at Cambridge a few weeks back. I don't suppose this news will surprise him very much.
The University of Colorado’s Sea Level Research Group decided in May to add 0.3 millimeters -- or about the thickness of a fingernail -- every year to its actual measurements of sea levels, sparking criticism from experts who called it an attempt to exaggerate the effects of global warming.
The story seems to be that the land is rising, increasing the carrying capacity of the oceans. This would effectively reduce the amount of sea level rise expected, and we couldn't have that - hence the "adjustment". The effect of the adjustment appears to be small when put against the projected rises, but is certainly material against the actual changes recorded (although these are, per Morner, wrong).
Reader Comments (164)
Was about to recommend Bishophill to a CAGW-inclined acquaintance but have decided to take a rain check after this thread's protracted schoolboy nonsense. Nearly 40 variations on Jack's marginally humorous duck comment so far. Sorry, much too lightweight for a serious blog. Moderator where were you?
Dave S. Portsmouth is built on historic mudflats, separating estuaries, presumably carved out by rivers during eras when flows were signficantly greater than they are today.
It is flat and level, ideal for cyclists. None of the natural topography can be more than 3m above the high water level, much is below, being reclaimed land, behind sea defences
I, would guess that a 1-2m rise in sea level might affect Fratton Park, so based on early IPCC predictions it was flooded out last century. Meanwhile, back in the real world, in the naval dockyards of Portsmouth and Devonport (Plymouth) dry docks built a few hundred years ago have not been inundated by rising sea levels.
Portsmouth FC may be in danger of going under, but sea level has nothing to do with it! You may then need the wellies, if it becomes a building site
The village of Bosham, near Chichester has cottages built very close to the High Water mark. Many have raised threshholds, possibly implying that sea level has increased since construction. None of these raised threshholds appear recent, apart from those obviously rebuilt, or replaced with demountable flood barriers
Thought I ought to make a serious, duckless post today!
@simon abingdon
Of course you are right.
No real CAGW supporter has anything like a sense of humour..and would no doubt look upon any such frivolity with great distaste. After all the complete destruction of our planet and all life thereon is a very serious business. And saving the world must start now. No time to lose. If we are all going to fry in a fortnight, there is much work to be done.
Perhaps you should direct him to an American blog, like Judith's. No relaxation from serious matters there.
In the same vein as the Sea Level Centre being half-way up the Rockies/0.3mm sea level rise business...
About twenty miles from the sea, on the borders of Kent and Sussex, lies Bodiam Castle. Nice day out for pensioners (alright, like me); school children; and all sorts in between. Nice tea rooms/souvenir shop etc. All run by the National Trust.
Alongside the car park meanders a small river; and on the bank (some 6/8ft above it) is an informative plaque describing the importance of the river in days gone by for the local iron industry.
Astonishingly, at the end, the writer goes completely bonkers - 'Enjoy this site now, because due to global warming in a few years time it will be under water...'
WHAT..??
David re Bodiam Castle
I do hope they have notified their building insurers of this risk. Should they have some form of flood, and try and claim on their insurance policy, they would be accused of fraud for not having declared that flooding was inevitable as opposed to a possibility
Re Shub
True. Look at the number of modern radio devices and radar systems that emit in the microwave range. Microwaves heat water, which obviously creates warming in the atmosphere. No suprise global warming correlates with the communications age. Obvious solution is to use more fibre, which means more work for me and I need the money.
Re Simon Abingdon
If you don't see the funny side in attempting to redefine sea level so it matches simulated sea level rises, then there may be no hope for you.
Atomic Hairdryer
Can you cook duck a l'orange with this freely available microwave energy, or are the energy levels available only sufficient to cook sea level data?
Jack, wonderful line about the duck... And Latimer, the webbed feet. To be honest I can hardly keep up this week, it has been hilarious from blog coast to coast.
And this thread is the hilarioust...
Latimer
On the contrary, the exchanges on Climate etc are not always humourless. As you know, even the unpopular Martha showed an unexpectedly light touch with her recent Lynus joke. (Needless to say the allusion was lost on me too).
Re golf
Yes, but it's like having a global temperature or sea level as any kind of valid metric. Place duck in front of any decent OTH radar system and the ERP will probably cook it, just make sure the duck is on the end of a very long hockey stick.
Atomic Hairdryer
Thanks for that, but my hockey stick is a bit broken. I think I could lash it together, but will tuff tape and bindatwine be degraded by the microwave energy? Or even catch fire in an alarmist sort of manner?
But if the duck was made from wood, would it float or sink....I can't remember witch....
Atomic Hairdryer
Yes it was funny. I just didn't need to spend all evening laughing uproariously at the same joke endlessly retold.
Simon Abingdon
In a week that has seen a science gamechanger - it might be the sun after all, followed by more IPCC irregularities over Greenpeace involvement and their funding, plus a staunch AGW supporter saying "hang on a sec chaps is this really ok", and the MSM just walks on by?
Who gives a flying duck?
By the way, is it only me that has noticed that in this era of AGW, the number of people with three "flying ducks" displayed proudly on a wall has declined significantly?
Another clear indicator of a warming planet
Re golf
Now you're thinking like a RealClimate scientist. All you're missing is the grant request and funding. Triple it to pay for the CPU's you'd need to model it rather than doing the experiment the old fashioned empirical way.
But if the duck was made from wood, would it float or sink....I can't remember witch....
Jun 18, 2011 at 11:29 PM | Tony Hansen
This would depend on whether or not you are philospher, and whether or not you would be present to witness the flotation test
Witches floated and therefore deserved to be drowned, innocents just drowned and therefore deserved to be apologised to, belatedly
golf charley
This thread's apparently carnival atmosphere in celebration of your supposed "science game-changer" may be premature. There is still a war on. Constant vigilance, as Margaret would have said.
Atomic Hairdryer
You think I could earn loads of money with this kind of rubbish?
Wow! Where do I sign on
Do I get paid by how stupid my theories are, or how outrageously and stupendously incredulous they are. Could I get into the Ehrlich money making scam (job for life just keeping stating stupid predictions) or would I fall into the zero-hero-zero mann camp with a 15 year max life expectancy?
ps No duck references in this post
Simon Abingdon @ 11:24 and earlier
Agreed.
Simon,
I agree with you.
But...
I was just thinking about this,...you must know about this concept of the Overton window - the relatively narrow range of ideas or set-ups people are willing to consider plausible, whilst dismissing others just outside of it. What happened with the Greenpeace thing was that a small Overton window opened and, purely as an emergent phenomenon, there were commenters to argue civilly, without shouting, abuse or namecalling and hold that window open. As a result (and of course, primarily and in no small part due to McIntyre and Mark Lynas, holding the line), this mistake by the IPCC was picked up by a wider circle. (a surprising change from the cynicism expressed by J4R to which I agreed with, and still agree). Yes, Lynas might have pulled some strings with his friends, but the resulting articles actually contained deeper, newer information about the IPCC report as well.
I don't say the above in any self-congratulatory way, but more to stress on the emergence aspect of it. This wouldn't have happened, without BH readers' good 'work' and it was completely unplanned and uncoordinated. Back to vigilance. :)
golf charley
This thread's apparently carnival atmosphere in celebration of your supposed "science game-changer" may be premature. There is still a war on. Constant vigilance, as Margaret would have said.
Jun 18, 2011 at 11:54 PM | simon abingdon
You are missing the point. What should have been a game changer, has been missed by the MSM. The AGW alarmists have however retaliated, predictably, via Bob Ward et el, to keep the MSM on message.
I do not know which Margaret you refer to, but I do not consider that the game has been won
Q: What does the IPCC have in common with a duck?
A: They can both stick their bills up their arse.
You've been a wonderful audience, I'm here all week.
It's said that if you pour water on a duck's back it runs off.
Well, if you poured water over my back, so would I.
"I don't think there is the remotest possibility that either of them ever visit this blog,"
Wooster: I say, Sir P., have you seen Bishop Hill's blog?
SP: Blog? Blog you say? What, pray tell, is a blog?
Wooster: It's...it's sort of a place where ordinary people can vent their spleens.
SP: Vent their spleens? Surely you mean bog. And what is a Bishop doing in a bog?
Wooster: No, no, Sir P. They write notes for each other to read, that sort of thing.
SP: On the walls, I presume. In crayon?
Wooster: Well, there are no walls, as such--
SP: No walls? No walls? That will never do.
Wooster: You don't understand. It's something on the Web.
SP: Web? I've seen webs in the bog. Bloody nuisance. Didn't dare sit down. Ruined my afternoon.
Wooster: But the Web is better than a newspaper--
SP: Bloody 'ell! A web is better than a newspaper? Have you been drinking, Wooster?
Wooster: Surely you've heard of email?
SP: I have, and I don't wish to be reminded of it, if you please.
Wooster: Well, a blog is like email. Only everyone can look over your shoulder. And everyone writes on the same virtual piece of paper--
SP: I don't want to hear it, Wooster. I think you've lost your mind, what there was of it. Good day!
Wooster: But you don't understand, Sir...Sir?
The ducks are fighting back!
Duck causes race chaos
No plastic ducks have ever made it across the Arctic Ocean before now.
Another clear indicater of a warming planet
Why, a Duck?, indeed! --The Founders of "Climate Science", Graucho, Harpo, Chico, Zeppo. And they alone saw it half-sunk.
.
Gixxboy
The DMI is into CAGW as much as in other countries, but they do not fake their data.I guess that is not something we do in Denmark. I guess that when it has been trough NOAA og something similar, we have a rising trend.
@ The Army & Navy Store counter assistants (Latimer & Golf)
I'll have you know our gate last year was an average of over 22,000. More than both your teams put together! Golf, you'll see what happens when we jump off chairs this coming season. Can't wait. Latimer, well you're back in the FL, so who knows what might happen over the next few seasons. Good luck to both of you (apart from Golf in the two games against us, of course) :)
Scummer FC Fan
@ Mike Jackson
Silly bugger. Everyone knows Watford Gap is the Scottish border ;)
Meanwhile, back on topic.....
What we are seeing here are desperate acts by desperate people. They know empirical measurements are not going their way. They know that we're all going to shout loud about these "adjustments", but they do them anyway, for two reasons. Firstly, they hope they can get away with it. Secondly, they don't know what else to do. There's no Plan B.
Sounds like tinned soup instructions -
Just add water.
Simon Abingdon - agree to some extent. But there is so much drivel doled out in the CAGW "debate" that occasionally there is a place for ridicule.
Latimer Alder,
"Why is the SeaLevel Centre at about 7000 feet up?"
They wanted to emphasize how bad the problem Gore pointed out really is and get dibs on favored property before everyone else started running from the rising oceans!!! 8>)
Based on the comments here, the University of Colorado’s Sea Level Research Group can be said to have scored a duck.
Humour, ridicule even, is a powerful force, and in this instance has focused attention on yet another dubious fear story; which is a part of the international fraud which Big Climate represents -- regardless of whether the Colorado Group realised this or not -- and I am charitable enough to believe they probably did not.
Laughter really is the best medicine, and may prove yet to be the medicine which cures this particular madness.
One (Josh) picture is worth a thousand words... which is a point to ponder.
Some critics argued the British cull of ruddy ducks was pointless unless other European countries also took action. But the RSPB continues to back the actions of the UK government.
That reminds me ......
Afraid I have difficulties seeing what all the fuss is about.
Glacial isostatic adjustment (GIA) is made because the ocean basins are slowly getting larger. Magma under the earth’s crust is flowing away from beneath the ocean basins (which are therefore dropping) into formerly glaciated land areas no longer bearing the weight of the ice, which are rising. As the ocean basins get larger, mean sea levels fall – GIA (in isolation) causes mean sea levels to fall by 0.3 mm/year (about 1.2 inches/century), a non-trivial amount.
The more difficult question is how GIA should be accounted for. Rather than reducing sea levels retrospectively (which is the true effect but would no doubt produce protests from the conspiracy theorists) the GIA adjustment is added, to produce a uniform measure taking the adjustment into account. It is only then necessary for the data to record that this uniform adjustment is being made and/or to give its current value.
The http://sealevel.colorado.edu/ site presently contains an explanation of the “controversy” around this adjustment - including “We would also suggest consulting the other unaffiliated sea level research groups around the world that independently estimate global mean sea level from altimetry and also apply the scientifically well-understood GIA correction.”
The essential reason for the adjustment is that, if you wish to have a measure of the *volume* of water in the oceans (to be able to see the quantity of water running off land-based ice) you have to adjust the raw height measurement to account for the increase in volume of the ocean basins.
Speaking of mathematical models, here's a question for the boffs out there for a layperson like me. I live in Christchurch, New Zealand which you may be aware has had a few earthquakes in the last 9 months. We have our esteemed geologists informing us via their "mathematical models" what the likelihood of further seismic events will be. Up until the 13th June there was apparently a 23% chance of a magnitude 6.00-7.00 shock within the general Christchurch aftershock zone within the next 12 months. On the 13th we had a 5.6 on a new previously unknown fault 10km east of us. Apparently now the likelihood has jumped up to 30%. My question is this, how could a mathematical model be formulated if all the contributing factors (new fault) are not known. Could it be reciting figures spat out of a computer are more plausible than a simple "we just don't know".
@timc
Thanks for your explanation.
If the taxapyers of teh USA want to employ a bunch of guys in the Rocky Mountians and measure or estimate the vlume of water in the oceans, that's fine by me.
Just rename it the 'Volume of Water in the Oceans' Centre. Job done.
People's objections are to the dishonesty involved in calling it 'sealevel' measurements. which patently they are not. If you call it 'sealevel', you should measure the level of the sea, not some related but different characteristic.
Simples!
Latimer Alder,
"Why is the SeaLevel Centre at about 7000 feet up?"
Precautionary Principle.
TimC
Thanks for the explanation. But it does rather beg Latimer Alder's question over 'sea level' and what that means (if anything at all). If the issue is oceanic water volume, then should we not be focussed on that? Does it (and issues of rising & subsidence in the land) mean sea level is meaningless as a measure?
Does anyone know if NASA ever got their rubber duckies back?
http://www.telegraph.co.uk/earth/environment/globalwarming/3886696/Rubber-ducks-elude-Nasa.html
Sorry for the delay in this contribution but domestic affairs forced me to duck out for the night.
Latimer, the Hull connection makes sense. Obviously from the days when it was more fun to follow Grimsby Town and watch them lose than stay at home and which Hull City lose!
LC
You are sorely mistaken.
1. "The North" begins at Watford (not Watford Gap). Scotland begins "up there somewhere". Turn left at the second "Here there be dragons" sign.
2. From the other angle (and I lived in Scotland for 40 years) and to understand the general contempt which the Scots have for the English, see 1. above.
To be fair the situation has changed since 1999 but I'm sure the Bishop doesn't want me to start on a polemic either about England being governed by Scotchmen or the 'West Lothian Question'!
TimC wrote: Afraid I have difficulties seeing what all the fuss is about.... As the ocean basins get larger, mean sea levels fall – GIA (in isolation) causes mean sea levels to fall by 0.3 mm/year (my emphasis)
If that had been what the report said, I wouldn't be able to see what the fuss was about either. But that isn't what the report said. It said:
The University of Colorado’s Sea Level Research Group decided in May to add 0.3 millimeters — or about the thickness of a fingernail — every year to its actual measurements of sea levels, (my emphasis)
Re TimC
I think the problem is again one of communication, and how the non-unfied theory of climate change will spin the results. Rising sea levels have been a big part of 'the fear' and central to the way global warming has been sold. Warming means more melting or thermal expansion and sea level rises which will threaten coastal areas. Computer models have predicted various rates of sea level rise, but observing those sea level increases has proven difficult.
The threat for communities is the relative rate of sea level rise to any land level rise or fall. If land is rising by 0.3mm a year and sea levels falling by 0.3mm then the threat is diminishing by 0.6mm a year and we're getting more land. There is no threat unless melt or thermal expansion overtakes the GIA effects. Or the +0.3mm land effect is non-uniform and some coastal areas are sinking rather than rising.
The Colorado adjustment looks rather artifical in that context and will no doubt be seized on by alarmists to show that sea levels are rising, it's worse than we thought and we must spend more money. They will probably gloss over relativity and eustatic, steric and isostatic variations, and focus on the +3mm increase that's been applied to claim, as usua,l that it's all evidence of global warming, and mislead. We sceptics may try to correct that misunderstanding but will just get shouted down as 'deniers'.
@Atomic, TimC, Jun 19, 2011 at 12:46 PM
Started writing something similar myself. Yours is better ;)
Atomic Hairdryer
Your explanation is so lucid (and so evidently correct as far as I can tell) that I wonder whether (a) there is more to this decision than meets the eye, or (b) the alarmists have finally shot themselves in the foot in a way which even the simplest mind can understand.
If the sea level on Brighton front or Bridlington harbour is still at the same level as it was 20 years ago vis-a-vis the quay or the sea wall then sea level has not risen, at least so far as the common man would interpret it.
To suggest that it has been "adjusted" to account for tectonic plate movement or post-glacial rebound or any other esoteric reason really is moving into "angels-on-the-head-of-a-pin" territory and is truly deserving of mockery.
Not to mention the extent to which it brings into the open the theory that if the observations don't match the models then it's the observations that are wrong.
I think this could be more important than the IPCC/Greenpeace scandal.
Geologists are looking at the data with suspicion. (I'm a geochemist, with geology by contamination). The evidence is plain. Those well-studied terraces that we can see on land, the ones that show ancient ocean levels - they are all above ocean level. Ergo, the ocean level is falling.
Tim C - Fine, lets assume the GIA is 3, 30, 300...3,000,000 mm or whatever. Not my field. But shouldn't we add it to the calculations of the calibration period for the anomoly and not just start to add it on in May 2011? Or has glacial isostaticism happened in the last month? Surely the decadal tend is the important metric. Presumably and hopefully they will add the GIA to all prior values so the tend will be as is was before. To add it as a step in in May 2011 and henceforth would be slightly un-scientific.
Non?
@ Latimer Alder: thanks for that.
Let’s take a worked example: suppose (to keep it simple) at 2000.0 the satellite ΔMSL figure (true - without any GIA adjustment) was 8.0 mm and the GIA adjustment was then 6.0 mm. In 2100.0 let’s suppose the figures are then ΔMSL 318.0 mm (no GIA adjustment) with GIA of 36.0 mm.
These figures are sufficient to give the true position whichever way round the data is presented.
If the ΔMSL’s are published as “true” figures, without current GIA adjustments, you will need to say “In 2100.0 we know that a century beforehand ΔMSL was plus 8.0 mm, but due to GIA effects that figure has actually now reduced because of GIA and become minus 22.0 mm. The actual ΔMSL figure today is plus 318.0 mm, a MSL rise of 340.0 mm”.
With the GIA adjustments (CU’s way): “In 2000.0 the GIA adjusted ΔMSL figure was 14.0 mm. The adjusted figure today is 354.0 mm, a GIA adjusted MSL rise of 340.0 mm. In 2000.0 the GIA adjustment was 8.0 mm; the adjustment today is 36.0 mm”.
Without the GIA adjustment you just get the ΔMSL figure which is a moving target getting progressively out of date by this 30mm/century (for which manual adjustment must be made for any comparison on a “constant water volume” basis). With the GIA adjustment you get both ΔMSL, the current GIA adjustment figure and a measure of the total volume of water in the oceans.
Of course you could ask CU to present 2 charts, one of the unadjusted ΔMSL figures and the other exactly the same figures adjusted by this 0.3mm/year. This seems rather excessive if the one chart is properly labelled to show what it actually represents.
This thread is maddening.
What matters here is that the satellite instrument package flown on Jason-2 has a measurement uncertainty in CENTIMETRES and the numbers everyone is arguing about are the end product of multiple stages of adjustments.
When I am presented with a trend estimate an order of magnitude smaller than the measurement uncertainty in the instrument making the observations, I take close note.
When the claimed uncertainty on the supposed trend is 0.4mm or two orders of magnitude smaller than the measurement uncertainty on the instrument I become sceptical.
I posted all this up at Jun 18, 2011 at 11:41 AM but everyone seemed to want to talk about ducks etc.
Also, let's not forget that the trend derived from actual tide gauges is ~2.8mm/yr (+/-0.8) compared to ~3.2mm/yr (+/- 0.4) for GIA-corrected satellite estimates.
- How much confidence can we have in the satellite estimate given the huge amount of signal processing that goes in to it?
- How much confidence can we have in the tide-gauge estimate?
- What is the difference between accuracy and precision?