This is a bit of a bombshell to those that claim sea level rise is accelerating and certain. From the University of Southampton:
Back to the future to determine if sea level rise is accelerating
Scientists have developed a new method for revealing how sea levels might rise around the world throughout the 21st century to address the controversial topic of whether the rate of sea level rise is currently increasing.
The international team of researchers, led by the University of Southampton and including scientists from the National Oceanography Centre, the University of Western Australia, the University of South Florida, the Australian National University and the University of Seigen in Germany, analysed data from 10 long-term sea level monitoring stations located around the world. They looked into the future to identify the timing at which sea level accelerations might first be recognised in a significant manner.
Lead author Dr Ivan Haigh, Lecturer in Coastal Oceanography at the University of Southampton, says:
“Our results show that by 2020 to 2030, we could have some statistical certainty of what the sea level rise situation will look like for the end of the century. That means we’ll know what to expect and have 70 years to plan. In a subject that has so much uncertainty, this gives us the gift of long-term planning.
“As cities, including London, continue to plan for long-term solutions to sea level rise, we will be in a position to better predict the long-term situation for the UK capital and other coastal areas across the planet. Scientists should continue to update the analysis every 5 to 10 years, creating more certainty in long-term planning — and helping develop solutions for a changing planet.”
The study found that the most important approach to the earliest possible detection of a significant sea level acceleration lies in improved understanding (and subsequent removal) of interannual (occurring between years, or from one year to the next) to multidecadal (involving multiple decades) variability in sea level records.
“The measured sea levels reflect a variety of processes operating at different time scales,” says co-author Dr Francisco Calafat, from the National Oceanography Centre. He adds, “One of the main difficulties in detecting sea level accelerations is the presence of decadal and multi-decadal variations. For example, processes associated with the North Atlantic Oscillation have a strong influence on the sea levels around the UK over multi-decadal periods. Such processes introduce a large amount of ‘noise’ into the record, masking any underlying acceleration in the rate of rise. Our study shows, that by adequately understanding these processes and removing their influence, we can detect accelerations much earlier.”
Co-author Professor Eelco Rohling, from the Australian National University and formerly of the University of Southampton, adds:
“By developing a novel method that realistically approximates future sea level rise, we have been able to add new insight to the debate and show that there is substantial evidence for a significant recent acceleration in the sea level rise on a global and regional level. However, due to the large ‘noise’ signals at some local coastal sites, it won’t be until later this decade or early next decade before the accelerations in sea level are detection at these individual tide gauge sites.”
The findings of the study, funded by the Natural Environmental Research Council (iGlass consortium), are published in this months issue of the journal Nature Communications.
Leo Geiger thinks the world is spinning around him but it seems he’s the Spinnmeister, himself.
His post goes;
“And what does this paper say about that Houston and Dean “bombshell”:
Thus, our analysis implies that the argument presented by Houston and Dean is invalid….it is intriguing that arguments persist that because only small accelerations are presently evident, the IPCC sea level projections must be wrong, when in fact the observations over the last 20 years agree closely with the Third Assessment Report and AR4 projections and are statistically consistently with AR5 RCP8.5 projections.
That part didn’t get mentioned here.”
Well, Leo elects to put a few dots in instead of the actual text. Here’s some of what was actually written;
“Thus, our analysis implies that the argument presented by Houston and Dean21 is invalid. In fact, by simply visually inspecting the projections from the earlier IPCC Third Assessment Report and Fourth Assessment Report (AR4), it is clear that only small rates of acceleration were predicted by the IPCC models for the period from 1990–2010.”
So, this paper’s contention is not that H&D were wrong about sea-level rise; they were wrong to dismiss the IPCC’s upper estimate because that was not supposed to have been realized yet anyway, it’s a prediction.
Just for fun, the opening sentence in this paper’s introduction is:
“A rise in global sea level is one of the most certain consequences of climate change.”
So, no matter cooling or warming, sunning or clouding, wetting or drying, the tide’s coming in, boys and girls.
So many of you have leaped onto this with immediate scorn. I didn’t see any mention of models in what was presented on site. I got the impression they want to review empirical data and try to filter out competing sea level processes where they could measure them and perhaps come up with some useful data for particular locations 20 to 30 yrs time. I didn’t get a big impression of a large barrow being pushed. So, good on them. All to often I find myself being repelled by responses that sound like warmist ad hominens.More good discussion, please.
PoF,
They might get an easier ride if they didn’t make exaggerated public claims that are not in the paper itself. Just because everybody else does it, it doesn’t make it right.
Beenstock et al at http://econapps-in-climatology.webs.com/SLR_Reingewertz_2013.pdf find a rise of around 1mm/year historical long term tide gauges. They make the quite important point that some tide gauges were emplaced because the rise was thought to be anomalous or abnormal and they should be rejected. Then you get arguments about whether this is cherry picking or mandatory data selection for quality.
Some tide gauge locations show a present fall, some a present rise, many neutral. Cherry picking possibilities again.
Of course it is all disputable because we have no idea of the magnitude and shape of contractions/expansions in the deep oceans that comprise about 50% of all ocean volume. These will also affect surface falls and rises, magnitude currently unknown, therefore tight uncertainty when quoted is a sick joke.
Re satellites, see Wu et al 2011 for a version of change that is not so often seen as it comes from a different aspect of research. I think.
Accuracy of the International Terrestrial Reference Frame origin and Earth expansion
X. Wu,1 X. Collilieux,2 Z. Altamimi,2 B. L. A. Vermeersen,3 R. S. Gross,1 and I. Fukumori1
GEOPHYSICAL RESEARCH LETTERS, VOL. 38, L13304, doi:10.1029/2011GL047450, 2011
Let’s say I am driving along going 55 miles per hour. And you, you monitor this event for 5 minutes, then 10 minutes, then 30 minutes. For the entire time the speed is 55 mph. The question is asked, after how many minutes of monitoring will you be able to tell that 2 hours later the speed will increase, decrease, or not change? The question can be asked in a similar vein if during the first 30 minutes there is a slight acceleration noted, or if there is a slight deceleration. What will be going on 2 hours later?
Here is a pithy comment that applies to this study:
http://www.phrases.org.uk/meanings/114000.html
“As cities, including London, continue to plan for long-term solutions to sea level rise”
WHAT
the London` plate` is declining into the English channel, we have known this since it was first accurately measured back in the 50`s !
perhaps they should have included the word “relative”
regards
“””””…..mark in toledo says:
May 9, 2014 at 3:19 pm
I would love some really good data on Sea Level Rise and Ocean Heat Content. I notice these are two areas where the alarmists love to camp since nothing else is going their way……”””””
So if I give you the “really good data” that you want; what is it that you intend to do with it ??
Why on earth would ANYBODY care about such data; about which, we can do precisely nothing.
Political Junkie says: May 9, 2014 at 4:41 pm ‘half way up a duck’
Depends if you’re a drake or a duck (at least during springtime).
OK………………I’ll see your 2007 AR4 “business as usual”/”worst case”/”upper error bar” A1F1 scenario by 2099 of +0.59M amsl, and raise you tenfold (an order of magnitude) to the lowest estimate of the 2nd thermal excursion of the end-Eemian (@highstand of +6.0M amsl) http://www.uow.edu.au/content/groups/public/@web/@sci/@eesc/documents/doc/uow045009.pdf
Cards, Gentle-people?
From somewhere in the troposphere “deck” you draw a pair of Goricals at +6.0M amsl’s each (about 40′). Smile and tell, you Biden.
I trade one card to the dealer. I draw a wild card (+52.0M amsl) http://lin.irk.ru/pdf/6696.pdf) from the top of the end-Holocene deck.
You are feeling pretty confident, and it’s your bet! You double-down…….after all, at the very least, you have a pair of Goricals…….
I look down at the possible/probable end of the most recent interglacial (http://wattsupwiththat.com/2012/03/16/the-end-holocene-or-how-to-make-out-like-a-madoff-climate-change-insurer/) in my hand, scrutinize the rather paltry pot, and raise you to +52.0M amsl (+101 ft amsl).
And call.
What occurs next is known as a “pause for reflection”. Once again, it is now your bet. The end-Holocene pot is now nearly 2 orders of magnitude worse than the worst case you recently thought (nearly 2 orders of magnitude above your AR4 bet~~~~)
It’s starting to get “hot” (also known as global cooling), you are starting to sweat…… You look at your “pile” and realize that all you have left (after Solyndra/A123/Fisker et al) are the WAIS and GIS (western Antarctic and Greenland Ice Sheets)!
(How much of both qualify as “liquid assets” at the climate change table?)
You go all-in~~~~
The most enjoyable part of this climate change game is counting the cards. Sure, we haven’t really seen all that much of the climate change deck, but wouldn’t it be fascinating if H. sapiens removed the only prognosticated climate security blanket supposedly thermal enough to obviate onset of the next glacial inception?
Talk about ironic!
“The onset of the LEAP occurred within less than two decades, demonstrating the existence of a sharp threshold, which must be near 416 Wm2, which is the 65oN July insolation for 118 kyr BP (ref. 9). This value is only slightly below today’s value of 428 Wm2. Insolation will remain at this level slightly above the glacial inception for the next 4,000 years before it then increases again.”
http://www.particle-analysis.info/LEAP_Nature__Sirocko+Seelos.pdf
Nature Communications 5, Article number: 3635
Published: 14 April 2014
doi: 10.1038/ncomms4635
Timescales for detecting a significant acceleration in sea level rise
I. D. Haigh, T. Wahl, E. J. Rohling, R. M. Price, C. B. Pattiaratchi, F. M. Calafat, S. Dangendorf
One has to be able to understand their quest. It is not about whether an acceleration term necessary to attain high end IPCC sea level rise projections by the end of this century can currently be detected, because it can’t. All data available so far are consistent with zero or even negative acceleration, which excludes anything above a foot or so.
What they are doing is to assume a century scale sea level rise in the meter range or above, which would not only require a strong positive acceleration, but an increasing one. The question they ask is when would increasing acceleration cross the detectability threshold.
In other words, they are focused on postponing the date when dire projections get falsified, should zero or even negative acceleration actually be the case.
Please note an acceleration of 0.1 mm/yr², which they expect by “the second half of the 21st century” is preposterously high and is well outside any reasonable range indicated by measurements. It would imply a two orders of magnitude acceleration of observed rate of sea level rise on a century scale.
“Such processes introduce a large amount of ‘noise’ into the record, masking any underlying acceleration in the rate of rise.”
Or mask ANY change in sea level?
The shot of the tide gauge at the National Oceanography Centre in Liverpool, UK is very funny. Have they set it to measure anticipated rise?
To determine rises or falls in sea level you need to know the height of your tide gauge with respect to a particular datum.
Featherstone and others [2012[ show that there has been subsidence of 5 to 6mm /year in the Perth Basinin the recent past, slowing to around 2mm/year in the past 5 years, due to ground water extraction. The location where the subsidence was measured is about 20km north of the Fremantle tide gauge. Levelling data for the gauge at Fremantle are less certain but the suspicion must be that there has been subsidence around the tide gauge.
http://www.cage.curtin.edu.au/~will/Featherstone53-62.pdf
If there is this uncertainty regarding Fremantle what of the other gauges ?
The paper by Haigh is important but it does not say anything really new
The results are essentially written in
Scafetta N., 2013. Multi-scale dynamical analysis (MSDA) of sea level records versus PDO, AMO, and NAO indexes. Climate Dynamics. in press.
http://link.springer.com/article/10.1007%2Fs00382-013-1771-3
Where it was demonstrated that the sea levels are oscillating and there is a need to take into account these oscillation to properly understanding the background acceleration.
What Antony call “new method” of analysis was actually taken (with minor irrelevant modification) from my paper that is extensively cited in Haigh’s paper, although Haigh et al did not fully get the physical aspect of my work.
See my web-page for the paper.
Stephen Rasey says:
May 9, 2014 at 7:31 pm
Key West (why keep this one and not the other 2? Pensacola and Fernandia )
=============
Because the old literature assumed it was far away from any thing that was moving or sinking…. it’s supposed to be on an ancient coral reef
..and once something like that is in the literature…..it stays
..of course, it’s way wrong
Key West is not only sinking, it’s moving NW
Bill Illis says:
May 9, 2014 at 6:37 pm
Do you think a single satellite operating at the same altitude using just radar bouncing off the variable sea surface is going to get down to the less than 1 mm resolution. I mean it is a joke that they are still in operation and anybody is taking it seriously.
Worse than that, how do they acquire the instantaneous SLP at the time of measurement; how do they correct for wind piling up the ocean against coasts; etc, etc.
John McClure says:
May 10, 2014 at 5:52 am
The shot of the tide gauge at the National Oceanography Centre in Liverpool, UK is very funny. Have they set it to measure anticipated rise?
It’s a radar gauge. I hope they account for the thermal expansion of their steel mount. 🙂
http://noc.ac.uk/science-technology/climate-sea-level/sea-level/tides/tide-gauges/tide-gauge-instrumentation?page=0,3
“By developing a novel method that realistically approximates future sea level rise …“. Until the future sea level rise occurs, how is it possible to know that the approximations are realistic?
I hope they aren’t into circular logic here (ie, applying their method to show that the present rate of sea level rise is higher than thought, because their method is based on it being higher in future.)
Err … who needs statistical certainty? Actually, whenever I see the tide come in, the sea rises at a frightening speed. Extrapolated it could swallow the Empire State Building in hours. Let’s get rid of the moon …