Public Release: 3-Dec-2018
Findings could help improve regional sea level forecasts
National Center for Atmospheric Research/University Corporation for Atmospheric Research
The pattern of uneven sea level rise over the last quarter century has been driven in part by human-caused climate change, not just natural variability, according to a new study.
The findings suggest that regions of the world where seas have risen at higher than average rates — including the Eastern Seaboard of the United States and the Gulf of Mexico — can expect the trend to continue as the climate warms.
The study, published today in the Proceedings of the National Academy of Sciences, was authored by scientists John Fasullo at the National Center for Atmospheric Research (NCAR) and Steve Nerem at the University of Colorado Boulder.
“By knowing that climate change is playing a role in creating these regional patterns, we can be more confident that these same patterns may linger or even intensify in the future if climate change continues unabated,” Fasullo said. “With sea levels projected to rise a couple of feet or more this century on average, information about expected regional differences could be critical for coastal communities as they prepare.”
The research was funded by the National Science Foundation, which is NCAR’s sponsor, the NASA Sea Level Change Team, and the U.S. Department of Energy.
Finding the signal of climate change
For the study, Fasullo and Nerem, both members of the NASA Sea Level Change Team, analyzed the satellite altimetry sea level record, which includes measurements of sea surface heights stretching back to 1993. They mapped global average sea level rise as well as how particular regions deviated from the average.
For example, the oceans surrounding Antarctica and the U.S. West Coast have had lower-than-average sea level rise, while the U.S. East Coast and Southeast Asia, including the Philippines and Indonesia, have experienced the opposite. In some parts of the world, the rate of local sea level rise has been as much as twice the average.
Regional differences in sea level rise are influenced by where heat is stored in the ocean (since warm water expands to fill more space than cold water) and how that heat is transported around the globe by currents and wind. Uneven sea level rise is also influenced by ice sheets, which lose mass as they melt and shift the gravitational forces affecting regional sea surface height.
Natural shifts in ocean cycles — including the Pacific Decadal Oscillation, a pattern of sea surface temperatures similar to El Niño but longer lasting — are therefore known to affect sea levels. So scientists were not surprised to find that as the ocean rises, it rises unevenly. But it’s been difficult to say whether these natural cycles were the dominant influence on regional differences.
To investigate the role of climate change, the scientists turned to two sets of climate model runs, known as “large ensembles”: one created using the NCAR-based Community Earth System Model and one created using the Earth System Model at the National Oceanic and Atmospheric Administration. These large ensembles — many model simulations by the same model, describing the same time period — allow researchers to disentangle natural variability from the impacts of climate change. With enough runs, these impacts can be isolated even when they are relatively small compared to the impacts from natural variability.
The climate models suggest that in regions that have seen more or less sea level rise than average, as much as half of that variation may be attributed to climate change. The scientists also found that the impacts from climate change on regional sea level rise sometimes mimic the impacts from natural cycles.
“It turns out the sea level rise response to climate change in the Pacific resembles what happens during a particular phase of the Pacific Decadal Oscillation,” Fasullo said. “This explains why it’s been so difficult to determine how much of the pattern was natural or not, until now.”
Improving forecasts
The research findings have implications for local officials, who are interested in improved forecasts of sea level rise for the areas they oversee. In the past, forecasters have had to rely on the global rate of change — about 3 millimeters a year and accelerating — and knowledge of the uneven regional impacts associated with continued melting of the ice sheets covering Greenland and Antarctica.
The findings add the possibility that the regional patterns of sea level rise tied to climate change can also be included, because the models predict that the regional patterns observed in the satellite measurements will continue into the future.
“We now have a new tool — long-term satellite altimeter measurements — that we can use to help stakeholders who need information for specific locations,” said Nerem, a fellow of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado Boulder and a professor of aerospace engineering.
###
About the article
Title: Altimeter-Era Emergence of the Patterns of Forced Sea Level Rise in Climate Models and Implications for the Future
Authors: John T. Fasullo and R. Steven Nerem
Journal: Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.1813233115
The University Corporation for Atmospheric Research manages the National Center for Atmospheric Research under sponsorship by the National Science Foundation. Any opinions, findings and conclusions or recommendations expressed in this material do not necessarily reflect the views of the National Science Foundation.
Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.
Fantasy…sea level rise of a couple of feet….Fantasy
Hey, that’s only 610mm! C’mon…do the math:
2101-2019 = 82 years
Currently it is 2mm/y avg. If it rises at an exponentially increasing rate we might not even notice any change for several years. If it rises at a steady rate it should be noticed after one or two years.
82*2=164
610-164=446
446/82=5.44 mm/y increase over the baseline 2.0
Starting at 0.0 increase and ending at (5.44*2) = 10.88 it is an increase in the rise of
10.88/82=0.133 mm per year, per year
2.0 this year, 2.133 next year, 2.266 the year after that, then 2.4 and so on.
In the last year it would increase 12.88 mm per year. When you consider that is >6 times the current rate it means th oceans would have to absorb heat at >6 times the current rate too.
If we accept that there is presently 333 W/m^2 of “back radiation” (Trenberth 2009) it implies an increase in back radiation to 2145 W/m^2 because the sun’s not going to get any brighter by then.
Wow! You have to admire a computer program that can get that much something out of so little nothing. If that happens some skeptics are gonna have some ‘splaining to do!
“If that happens some skeptics are gonna have some ‘splaining to do!”
Classic! Sublimely formulated and delivered!
rip
Sea level rise is driven by cosmic radiation alone.
It has *nothing* to do with climate.
You have X watts of upwelling radiation, and Y watts of downwelling radiation. Y includes backradiation and is slightly larger and upwelling radiation – let’s assume so for the sake of warming system.
Now it is not Y that is multiplied by six in the scenario, it is the imbalance Y – X, which is a small number, so small that is very difficult to say how much the imbalance is affected by real radiative effects and how much by say, latent heat changes and convection.
I don’t claim being a scientist here, but “do the math” is not exactly what you do above.
slightly larger *than*
It is past midnight here.
Lumpy data eh? Maybe they didn’t stir it enough …
I always thought they used a blender !!
I think they extrude the data through computer algorithms.
I thought they extruded data through their nether regions.
Which would explain the “brown” part of the “Brown to Green” program. The “green” part? Too much candy.
Homogeniser
““We now have a new tool — long-term satellite altimeter measurements ” With accuracy of 3.2cm as against postulated SLR of 3.2mm. 😛
That 3.2 includes padding for sea floor subsidence.
And Steve Nerem is the primary one behind including modelled sea floor subsidence into the altimetric measurements !!!
Whatever. If the sea floor subsides, the continents rise, which means the more sea floor subsides, the less sea level rises there where it matters.
I’m really getting bored with this goal-post moving. They’re just trying to keep the measure stick so that they could claim fast rise.
The data became lumpy because it received incessant adjustment of heat which was being hidden in the oceans
I learnt at a young age that hiding things under the carpet meant it left lumps but I didn’t know it worked with heat or water isn’t science wonderful or these people thick (or they think we are).
To give them the benefit of the doubt maybe they don’t know about waves and tides?
This video shows the effects of sudden and unexpected sea level rise.
https://www.youtube.com/watch?v=ppYgrdJ0pWk
James Bull
Why no mention of isostasy? This is unacceptable. They have started with the conclusion they want and worked backwards. Is this what now passes for scientific research in climate alarmusm ideoligy? Lump critical issues together or ignore altogether which may offend the politbureau? Also what about the well documented cases of groundwater extraction? This is not science this is junk posturing to satisfy a political agenda. Perversion for money!
The Earth’s crust moves up and down and that changes the apparent sea level on any shore. link The effect is well known. It happens fast enough to be the same order of magnitude as the natural sea level rise we’ve seen in the last two hundred years.
Here is a link to a good website on historical sea level rise in the last thousand years. Note that it is complicated. It is very difficult to say, with any accuracy, what the natural sea level rise should be at this point in time. It appears to have been accelerating since around 1800. Disentangling anthropogenic effects from the naturally occurring sea level rise by the use of satellite altimetry probably isn’t reliable given the ‘noise’ in the system. Note that according to Abb. 3 in this paper sea level changes in the last 3000 years have often been much more rapid than they are currently. In other words, the current change in sea level is completely within natural variability. You don’t need anthropogenic effects to explain it.
“In other words, the current change in sea level is completely within natural variability. You don’t need anthropogenic effects to explain it.”
of course you dont need AGW warming to explain it. It could be unicorns.
But there was an LIA. It is warming, and warmer water, well it expands. So, Since we believe there was an LIA, and since that implies it is warming ( else we would be in an LIA) then obviously the warmer world implies a rising sea level. And guess what? Its rising!
What you MEANT to say is that you doubted anthropengenic CAUSES, not effects.
So here is the challenge. There was an LIA. It is warming. And we would expect from that warmer water, expanding. and we would expect some added water to the ocean from melting landed ice.
So the sea level rise we measure is totally expected given a warming world. There is no silly need to fight the data. There was an LIA; its getting warmer; and the sea level is rising.
There is no NEED to say that anthro caused the warming, but there is a scientific desire and goal to explain things. Even if they are within “normal” parameters, we like to explain. Heck I dropped some rocks and they all took the same time to hit the ground. None were abnormal. Nothing to explain. So that a change is within “normal” parameters doesnt mean we dont ask why did it change?. Why is it warming? The best explaination, the only explanation is the increase in forcing from multiple components, including human related ones.
Excuse me SM, but to me it looks like you start out being logical and then give that up. If the normal, ie cycling into and out of glacial events and sub-events, like LIA’s, results in a sea level change of around 50 meters higher and 150 meters lower than current, how can you define AGW (disentangle in above report) signal against that background? Prof. Mann constructed a hockey stick to try to show an AGW signal as being detectable.
The other point geologists make about sea level is that there is no norm. Sea floor tectonism, volcanism, irregular sedimentation, isostatic rebound, all create an irregular and constantly changing basin, with attendant change in sea level.
The best explanation is…no one knows….it’s the same rate it was before global warming
No.
If you say ‘anthropogenic causes’ you’re really saying ‘human caused causes’. It’s redundant.
If you carefully parse what I said, you will find that your reply doesn’t actually address the issue.
I didn’t say there was no human contribution. I did say that purporting to quantify the human contribution, in the face of demonstrated natural variation, is bogus.
You invoke unicorns. Is that how you explain natural phenomena?
Sea level change ranges from -5.79 ft/100 yr (Alaska) to +5.31 ft/100 yr (Louisiana) according to NOAA long-term tide stations. Did this study conclude that sea level fall will also continue? I’ll go out on a limb and predict it will. The daily mean tide fluctuates more than 20 ft at many locations in both northern & southern hemispheres. Sea level changes may go unnoticed at many of these locations.
Steve with his English degree is attempting science and failing you have a radiative transfer all you need to do is change the polarization or albedo of the atmosphere and you can get a change without a single classical garbage forcing changing. That is what things like aerosols do.
Perhaps search the phrase
“No-Forcing and No-Matching Theorems for Classical Probability Applied to Quantum Mechanics”
You need to remember your stupid little classic calculations are only approximations and your classical predictions are predicated on the QM domain statistics remaining fairly constant. It is why when you take the classical formula junk too far they go into runaway and predict crazy stuff that can’t actually happen.
LdB
There you go using the word “polarization” again. What do you mean by that?
The earths atmosphere has charged particles in a magnetic field it leads to a number of polarizations at different heights. The one you should be most familiar with is Rayleigh which is the one that makes the sky appear blue.
We often talk about sunlight as in direct sunlight we experience as being unpolarized but that intensity is actually first affected by that which gets polarized on the way thru and the scattered polarization also has intensity as evidence by the fact you see a blue sky. So technically total sunlight is partially polarized or semi-polarized.
As a layman start point this will help, which covers how animals etc use it to navigate and how it persists even if it is cloudy.
https://en.wikipedia.org/wiki/Rayleigh_sky_model
That is not the end of the story there are other atmospheric polarizations and indeed the ocean itself has polarization perhaps a quick layman start might be
https://pdfs.semanticscholar.org/2617/3fa9b80fe0d762059afc5e41160a8d6848b7.pdf
What you might then want to do is checkout the QM interaction of two polarizing filters 🙂
These are the sorts of unknown unkowns in Climate Models and they run on the assumption they don’t and haven’t changed over history.
LdB
When I retired, my job title was Senior Remote Sensing Scientist, reporting directly to a well-known aerospace company’s Chief Scientist. My specialty was Imaging Polarimetry. Therefore, I have more than a passing acquaintance with atmospheric polarization phenomena, and Rayleigh scattering.
Your explanation reminds me of the sort of pseudo-science I would expect to encounter in something written by Immanuel Velikovsky or George Adamski. They were well known for throwing around some half-facts and ‘sciencey’-sounding words to impress the audience, who were ignorant of science. I suggest that you stick to insulting geologists because readers can immediately assess your believably.
The answer to “Why is it warming” is “We don’t know” assuming, of course, it actually is warming. Hard to tell with so few, and poor resolution, real data and a political drive to distort, er I mean homogonize and correct, the data.
And, of course, there is no proof available that current warming (see above) is not natural and just like historical warm/cool periods.
And as to the projections of future heating, based upon additional “unknown positive feedbacks”, no explanation why the planet’s “temperature” appears so stable, given the effect of positive feedback in systems.
Yes Robert, it is warming and there is data. But instead of “proxies” just go to the historical records. Henry VIII rode in his carriage from Buckingham Palace, down the Thames almost to the mouth. The river was frozen then, it is not frozen now, ergo it is warmer now.
There are heaps more in the records, people just have to read them.
Steven Mosher – December 5, 2018 at 2:01 am
I’m surprised that the above “tripe n’ piffle” sarcasm didn’t also make mention of the Flying Spaghetti Monster along with the unicorns.
Maybe it was because Steven Mosher wants to give the Flying Spaghetti Monster credit for the Medieval Warm Period when the ocean waters were a lot warmer than today and therefore the rising sea level during the MWP was far, far greater than what is happening during the current Late 20th Century Warm Period. “YUP”, iffen he can’t infer that CO2 caused the MWP then the FSM will be his likely choice.
“HA”, me thinks the current “warm period” of rising sea levels has a couple hundred years to go to be comparable to the MWP. And shur nuff, memory recall is only applicable when one has stored memories capable of being recalled.
The Medieval Warm Period (MWP), which proceeded the Little Ice Age, lasted from 900 to 1300 AD, approximately 400 years, with near-surface temperatures being about 2°F (1°C) warmer than modern temperatures.
Mosher, that may have been the dumbest thing I’ve ever seen you write. The incessant need to blame everything on humans, even when they are perfectly natural and within normal historical bounds, is nothing more then a sickness.
~¿~
If the rate is within the bounds expected for 100% natural response, how can you say with such confidence that there MUST be a human component.
Mosher, you and your friggin’ unicorns. Is this a fetish, or what? I might have to look that one up on-line.
“There is no NEED to say that anthro caused the warming, but there is a scientific desire and goal to explain things…..AS ALL BEING CAUSED BY ANTHRO GLOBAL WARMING”
FTFY.
Stephen Mosher said:
“and since that implies it is warming ( else we would be in an LIA) then obviously the warmer world implies a rising sea level. And guess what? Its rising!”
AND WE SHOULD BE WORRIED ABOUT THE THERMAL EXPANSION OF the ocean water?
When the rise has been 1.8mm per year and not accelerating. This is from tide gauges which are way more accurate than satellite measurements. Even the satellites give only 3mm per year and no acceleration.
http://inspectapedia.com/plumbing/Hot_Water_Expansion.php
Isostacy is taught in Earth Science 101. It would be almost impossible that none of the authors of this study were aware of it. They had to intentionally ignore it. Pathetic.
“To investigate the role of climate change, the scientists turned to two sets of climate model runs, known as “large ensembles”: one created using the NCAR-based Community Earth System Model and one created using the Earth System Model at the National Oceanic and Atmospheric Administration. These large ensembles — many model simulations by the same model, describing the same time period — allow researchers to disentangle natural variability from the impacts of climate change. With enough runs, these impacts can be isolated even when they are relatively small compared to the impacts from natural variability.”
I always get the Stephen Mosher that posts in here mixed up withe real Stephen Mosher who has done a lot of work investigating climate science. If they are one and the same then he needs to look at himself in the mirror and ask himself What is the real truth? The above quote from the study again proves just how garbage almost every climate study is. Using their own computer models to try to prove their point. Very sad. And has been pointed out in the above answers, forgetting the main reason of sea level change being tectonics and/or isostatic changes; is astonishing in a scientific study on sea level change.
The study is based on satellite altimetry. This is unaffected by continental crustal processes. The differences in the satellite data are due to wind patterns and barometric pressures. I guess these didn’t exist before Jimbo Hansen invented Gorebal Warming… but I am certain this was covered in my meteorology and/or oceanography classes back in the 1970’s. I think it’s even in Sverdrup, Johnson & Fleming (1942).
“The study is based on satellite altimetry. This is unaffected by continental crustal processes.”
How so?
David is 99.999…% correct. Satellites measure Eustatic Sea Level — the distance from the center of the Earth to the surface of the ocean. Tide gauges measure Apparent Sea Level and have to be corrected for isostacy if you want Eustatic Sea Level. And you do generally want Eustatic Sea Level if you expect to compare observations with other observations.
Clyde Spencer (below) is almost certainly correct that Sea Level changes do affect isostacy. But a lot of folks are going to be surprised and embarrassed if those changes turn out to be significant on a timescale of a few years or decades.
Don K – December 5, 2018 at 9:59 am
Yeah, ….. RIGHT, …… shur dey do, …… and within 1mm accuracy.
There was an article around 8 months ago in WUWT about the inaccuaracy of trying to measure the sea level by satellite. Since the world’s oceans are never completely calm and the winds whip the surface to different levels everywhere, can someone give a precise definition of exactly where the surface of the ocean is; that the satellite is trying to measure? In any case even the satellites are not showing acceleration of sea level rise.
David
No, a changing volume of oceanic water can affect the underlying mantle, both positive and negative. Extrusion and serpentinization at the globe-encircling spreading centers can decrease the volume of the basins. Normal faulting on the ocean floor can change the basin volume. And, changes in the rate of sedimentation at the deltas of the world’s major rivers can affect the rate at which water is displaced, and the load can cause isostatic adjustment of the underlying mantle, with bulging occurring on the edges. So, I’m sure that the ocean basins are in a constant state of flux, but we are not prepared to monitor it and assign numbers to the changes. The researchers are attributing all the changes to thermosteric increase and glacial melt, and ignoring the other crontributions.
did you also laugh when you read “The scientists also found that the impacts from climate change on regional sea level rise sometimes mimic the impacts from natural cycles.” ?
Unprecedented B…LL.s….T. This report is probably an ordered piece of work, so that the coming IPCC special report on Ocean and Cryosphere, next year, tallies.
“To investigate the role of climate change, the scientists turned to two sets of climate model runs, known as “large ensembles”: one created using the NCAR-based Community Earth System Model and one created using the Earth System Model at the National Oceanic and Atmospheric Administration. These large ensembles — many model simulations by the same model, describing the same time period — allow researchers to disentangle natural variability from the impacts of climate change. With enough runs, these impacts can be isolated even when they are relatively small compared to the impacts from natural variability.”
Let me translate. We have the two bigger than bigly computers, And we kept playing with them until after 367,893 games, we got the one we wanted.
Have you ever thought about changing your user name to “Warren in New Zevon”? That’s what I thought it said at first as I was scrolling past your post.
Did the authors even consider the effects of tectonic plate interactions? That would cause uneven sea level changes.
Have these ensemble computer models shown any skill at all? These are highly complex models which are likely operating as GIGO processors.
Mid-ocean, there should be no tectonic movement corrections at all. If the ocean surface is truly “not flat” as predicted by gravity, the group needs to explain WHY the physics model is incorrect. Or WHY the gravity field of the world is not uniform everywhere at sea level.
Of their sensors may be fouled up/algorithm is fouled up.
Gravity does not predict a flat sea surface. It predicts a equipontential sea surface. So, yes there will be tectonic corrections mid-ocean.
The reason why gravity at the surface is not uniform has been known, and explained for decades.
How can they? They admitted that they can’t gather the real-world data that could be used to show the skill of the models in separating that portion of sea level rise due to natural variability and that portion due to “climate change” (itself something that begs the question). It’s all a farce – they just operate on the assumption that the computer models are skillful because that’s the only thing they CAN do. And when someone questions the actual reliability of their methods, they just hide behind the “best science” canard.
Sorry, missed the typo. I am writing from my cell. I am obviously need ideological and typographic re-education for non conformist thoughts. Final observation. Does not this junk also undermine their argument for paying attention to global averaging of sealevel if now the latest desperate word from the Kremlin is to Mannipulate the sealevel Al Goreithm
Writing from your cell? Are you a monk?
Ha! Never thought of that option. (I thought maybe he was in jail)
This is as clear an example of data fabrication as I have ever seen. Just compare these two passages:
“It turns out the sea level rise response to climate change in the Pacific resembles what happens during a particular phase of the Pacific Decadal Oscillation,” Fasullo said. “This explains why it’s been so difficult to determine how much of the pattern was natural or not until now.”
“To investigate the role of climate change, the scientists turned to two sets of climate model runs, known as “large ensembles” . . . These large ensembles — many model simulations by the same model, describing the same time period — allow researchers to disentangle natural variability from the impacts of climate change.”
They do no such thing. A functioning computer does nothing more than what it was programmed to do by a person. It’s output is not data. Since these “researchers” admit that they can’t gather real data allowing an actual measurement of how much seal level rise is due to natural variability and how much is not, they turn to their computers in a pathetic act of desperation; they can’t gather evidence the scientific way, so they do it the unscientific way in order to produce their almighty “peer-reviewed research paper” – which if you think about it is the only measure they have of their own professional competence. Their papers – their mere words – are used as a substitute (a “proxy” if you will) for actual, demonstrated competence.
These guys aren’t scientists – they’re just professors or other academics playing at being scientists.
So… the anthropogenic bit is indistinguishable from the PDO bit.
But only in that limited set of circumstances commonly known as the real world.
In that higher plane of reality the real world is based off of, and that climate scientists are able miraculously tap into and measure using their computer models, the anthropogenic bit is easily distinguished from the PDO bit.
Can’t you see that?
Thus use of words like “data” “study” and “shown” by CAGW researchers has damaged science; real scientists in other fields should be protesting the use of such terms in climate science to describe runs of unproven models.
Almost correct most are refugees from other fields like English, Geology etc playing at science and often get the basics wrong.
Excuse me?? You’re seriously equating Geology with English and accusing geologists of “playing at science”?
Where’s David Middleton when you need him?
LdB,
Excuse me??? Are you seriously equating Geology with English and accusing geologists of “playing at science”?
Where’s David Middleton when you need him?
Sorry about the double-post. Thought I messed up the first one.
LdB
Perhaps you didn’t notice that you were previously taken to task for maligning geologists. You are insulting a large percentage of the commenters here. Please cut it out.
I happy to amend it to unless you have done studies in Radiative Transfer with your field you are playing at science and will likely get it wrong. Happy with that?
LdB
See remark above, December 6, 2018 at 12:12 pm
Kurt – December 4, 2018 at 10:43 pm
Right you are, Kurt, but, ………… the “fact-of-the-matter” is that during the past 60+- years the public has been nurtured (brainwashed) to believe that “the computer is always correct”.
And now days, a big, big majority of youngsters, teenagers and adults believe that “the computer is always correct” …… and it matters not how many times you tell them that the “gigo” of Climate Modeling programs is not to be believed, or trusted, …….. they will simply ignore your advice as if they had never heard it.
I call BS!
“…These large ensembles — many model simulations by the same model, describing the same time period — allow researchers to disentangle natural variability from the impacts of climate change. With enough runs, these impacts can be isolated…”
The average of a bunch of wrong things doesn’t give you a more right answer.
B-b-but they said right in the article that they disentangled the wrong answers from the right ones and gave us what was left. I am confident the computer knows it’s right hand from its left.
Indeed. Improving precision by multiple measurements is only possible for independent, equally distributed measurements. Multiple runs of the same model are presumably equally distributed but they are most definitely not independent.
Lets take an example of reading a distance along a rule to the nearest 0.1mm.
A machine will round to whatever it is programmed to; round up, round down, round nearest.
But humans will read predominantly high or low. So multiple readings in this case won’t help with accuracy. And it gets worse if you have to add the measurements, as the error will propagate and get larger.
tty
I want to quibble (and with Greg below) :
Precision and accuracy are not the same thing. Making multiple measurements does not improve the accuracy. It increases the precision (and reduces the uncertainty) about where the centre of the accuracy range is located – that’s all. Increasing the number of readings to a billion does not make the readings more accurate, and does not compensate for having an inaccurate instrument.
If the uncertainty about the original readings (all of them) is plus or minus 2, then the answer will lie within 2 of the centre of a range of 4, the position of that centre being known with great precision. This is fundamental to metrology. Knowing where the centre is doesn’t tell you where the true result is. Climatologists frequently report the centre of the range as if it is the true value. This is a fundamental error of metrology, indicating a lack of understanding of the basics.
Crispin in Waterloo
+1
And they use the mid-range value (median) a lot, which doesn’t improve precision no matter how many values they use.
Three consecutive “news” stories on the BBC website this morning could each be about the above sea- level pseudoscience:
“I was impossible to get a real job.”
“What happens when machines hallucinate.”
“What our science fiction says about us.”
1. “With sea levels set to rise a couple of feet this century…”. They are not. Global average sea level rise is well-established at 8 inches per every 100 years.
2. If human unfluences are thought to be responsible for regional rises in sea level, they could also be responsible for those areas where sea level has not risen in line with expectations (following the logic of these ‘researchers’.
3. The ACTUAL reason for the rise in sea level in localized areas is that these particular aquatic domains have seen extraordinary growth in turtle numbers. This is where data collection outstrips modeling every time. If these ‘researchers’ had actually been out on the oceans in these areas and investigated the large numbers of turtles on the surface they would have found them standing on other turtles beneath them with even more turtles beneath THEM. After that, of course, it’s turtles all the way down…
It is like throwing turtles into the pot until water shloshs over the edge. How many turtles equals a 12.5mm/year rise? Depends on the AVPT factor I guess.
My favorite part was this:
I’m sorry, but I started programming computers in 1963 … and if the half-century of writing code has taught me anything, it is that models are just the prejudices, understandings, and misunderstandings of the programmers made solid. Now they’ve run each model lots of times, and they claim (without proof or citation) that the longer they run it and the more runs that they average, the more accurate their results become.
Then they take the difference, observations minus models, and they declare (again without proof or citation) that that difference is the human contribution.
How many untested assumptions are there in all of that? I can’t begin to count, but it’s on the order of the number of tunable parameters in the models …
w.
An average, like any other statistical parameter, only tells you something about the population you are sampling. When they run their computer model over and over again, they are just obtaining more samples of the theoretically modeled climate, and the average only represents the expected value(s) of a very large batch of model runs. The more model runs you have, the more accurate that expected value becomes. But that contains no information per se about the real system being modeled, because the real climate system isn’t being sampled – the computer model is being sampled.
Thus, among all the myriad assumptions that went into the model, the only one that really matters is the assumption that the model accurately simulates the real climate. But the media blurb above admits that they can’t test that assumption by using real measurements.
Like I said above, this is a literal example of data fabrication. The “researchers” just think that it’s OK to use a computer to fabricate data if it’s not feasible to obtain real data.
Please be careful with words. It is fabricated but it is not data. The results are ‘outputs’.
I’m guessing you’re being sarcastic, but I am being careful with my words. Solely on the basis of the model results, they claim that “[b]y knowing that climate change is playing a role in creating these regional patterns,we can be more confident that these same patterns may linger or even intensify in the future if climate change continues unabated.” They go on to argue that certain coastal communities should start preparing for further sea level rise based on their models.
The press release states that, rather than being used to merely hypothesize the role of climate change on regional sea level rise, the models are used to “investigate” it.
Clearly, they are using the output of the computer models as if it were data.
I agree. Clearly they are using model outputs as it is was “data”. It is not, so I am suggesting we should not repeat their error in our communications.
I don’t think this is a matter of pedantry – the (common) mistake of claiming that some computer programme spit out “data” from a model is a serious error.
Data should be presented with an uncertainty, and anything calculated from that data should propagate that uncertainty. When two uncertain numbers (data) are processed through a formula, standard error propagation formulae are used to indicate to the reader what the total uncertainty after calculating the result.
You will notice that this is almost never done by NASA/GISS, for example. They often treat model outputs as data, and do not propagate the errors and report them alongside. That is why we see such things as the claim above that the modelers “teased out” some relationship between natural and human influence. Bollocks. They have done no such thing. The have produce GIGO: garbage in and gospel out. I therefore remain agnostic.
Pat Frank and Patrick Brown have been arguing against each other for years about the average cloud error per year in the models of 4.3W/m^2 . They both agree on the number but Patrick Brown says that is the total error offset. Pat Frank on the other hand says that even though that is the error per year, the climate models are in error on every calculation, so that a years worth of calculation would put the actual cloud error to be insanely large and unknowable since the error is propagated at every step in the calculations. Who is right and why? I lean toward Pat Frank since every computer model can never mimic the actual processes in the climate of a year. The computer models have to churn out their calculations based on equations ; however the actual climate does its thing by exactly duplicating the real world physics which the computer equations will never get right. Each equation calculation introduces physics error upon physics error ( not to mention the rounding errors) so that the total physics error range can never be knowable. Climate models have to cheat on all boundaries (spatial, time, and physics parameterization). Each cheat introduces error.
W Nordhous will receive Nobel prize for his economic model that includes climate models.
He was interviewed and sounded serious when he believed in his models accuracy.
Climate is not very hard to model was his believe.
If I can judge his model can be called “Hybris”
I hope this new model of sea levels have some connection to all the manual measurements that has been going on for many years-as this:
https://tidesandcurrents.noaa.gov/sltrends/sltrends_station.shtml?id=9414290
“…. and they claim (without proof or citation) that the longer they run it and the more runs that they average, the more accurate their results become.”
No they don’t say that – they say ….
” With enough runs, these impacts can be isolated even when they are relatively small compared to the impacts from natural variability.”
Just as NWP in weather prediction does, more runs pins down the chaos in the system due to starting conditions.
Tweak those a tad, say put the Nino in mid-Pacific rather than further east – and many more changes to the NV state – and they (say) that the effect of NV can be teased out by the model simulations.
In NWP FI the UKMO will, say, alter a PJS wind strength in a crucial (for storm development) location, alter the curvature within the trough. In some situations little difference is achieved, and the storm would still blow-up, but in some, then the storm may not materialise at all. Chaos inherent in the starting condition. Sensitivity. The determination of which giving, in the case of NWP, confidence levels for the forecasted outcome in the deterministic model.
There is no bias in the model conveyed by the modellers. Just the physics of fluid motion.
Just to be clear here, you seem to be drawing a distinction between precision and accuracy, noting that the authors of the paper are only making the claim that repeated model runs let them “isolate” really small “impacts” in their models from really large “natural variability” in their models, but there is no implication to be inferred that the authors are making any claim that the “impacts” or the “natural variability” are at all accurate relative to the real world.
If that is the case, and you seem to be saying that it is, what is the point of the paper? And why would the authors state that, given the model results, “we can be more confident that these same patterns may linger or even intensify in the future if climate change continues unabated?”
“There is no bias in the model conveyed by the modellers. Just the physics of fluid motion.”
Oh indeed? No parameterisations used anywhere?
Incidentally, when it comes to the physics of fluid motion the Navier-Stoke equations are still unsolved except for a few simple subcases. It hasn’t even been shown that they can be solved or that solutions even exist for all cases.
I worked for 40 years in the aerospace industry and these days we can sort of solve by numerical approximation for stable flow around solid objects, which means we use wind-tunnels much less. But we are still far from solving dynamical flow around a complete airframe with changing attitudes. Which is why we still build prototypes. And often still get nasty surprises.
Much less can we solve for the whole atmosphere, with varying topography, humidity, insolation, ocean interaction etc etc etc etc. And even if we knew how we would need computers literally trillions of times more powerful to actually do it.
Nick does the same he just thinks you can average anything, it doesn’t even matter if you are forbidden from averaging them because they have things such as cauchy distributions.
Once at University, I was performing an experiment which involved reading a current on an analogic instrument. Of course the error in the reading could not be better than half of the reading unit, but the professor (shame on him, must have been drunk) stated that reading it multiple times, we could get a smaller error.
Seems he was coming out of the same school as these… Reminds me of the infamous “Xerox Microscopy”
Willis Eschenbach – December 4, 2018 at 11:40 pm
And I started as a Logical Designer of computers in 63’ and if that is what the “climate scientists” are claiming, then it is of my learned opinion that the computer(s) being used by the aforenoted climate scientists for their “climate modeling” have been and/or are malfunctioning, either due to poor design, faulty electronic components, or whatever.
If one “runs” each model 100 times, …. or 1,000 times, ….. the output results should be the same every time.
If one’s CPU is not FUBAR, …… then a change to the “input” model is required to get a different output.
Sam, you’ve got it wrong.
I’m a latecomer, who didn’t start programming until 1967, but I can still keep an open mind on stuff. It’s been frequently pointed out in this forum that the GCMs include random number generators at numerous points, to ensure that they give different results every time.
However. The underlying assumption made by the modellers, that by averaging many runs of a computer simulation, each of which is “wrong”, you can get the “right” answer, is one that perplexes me. I need someone to explain this to me in simple language. If that’s possible.
I also need clarification, if it’s possible, as to why parameterization of clouds is valid, when the formation and evolution of cloud cover has to be affected by the processes being modelled. I can see why they need to do it, but needing to do it doesn’t validate it.
re: “averaging many runs of a computer simulation, each of which is “wrong”, you can get the “right” answer”.
This belief comes from the assumption that the model is accurate. Which of course, it can not be. There are too many uncontrolled variables, and too many variables that are not known well enough. Then there the natural fractal nature of nature itself, which defies modeling accuracy.
It can fall within a statistical mean, that’s the best we can do. And even that is only valid for a finite time period into the future.
Smart Rock – December 5, 2018 at 1:27 pm
Smart Rock, ….. I have to assume that you meant the above to be some sort of a dumb arsed joke, a pun or simply satire.
But it wouldn’t surprise me any to learn that some of those silly “climate scientists” actually proposed such idiocy.
Of course it would provide a damn good excuse as to why their GCMs can’t “predict” the current (2000-2018) climate (or weather) via the per se hindcasting of data that has been collected during the past 100-300 tears. 😊 😊
I’m having trouble with this statement:”The climate models suggest that in regions that have seen more or less sea level rise than average, as much as half of that variation may be attributed to climate change”.
Are Fasullo and Nerem claiming that in those areas where sea level rise is less than average, humans caused up to 1/2 of the difference from the norm? Of course I am assuming that they mean “human caused climate change” when they say “climate change”
Exactly how can any type of climate change over a period of less than a century, cause rate of sea level rise to be less in some regions than in others? They never mentioned isostatic rebound in their paper. Even if they are thinking of a change in isostatic rebound rates, how can they think humans have been able to slow those rates in some areas in such a short time span?
SR
Attributable does not mean avoidable. Attribution is a human proclivity. Attribution is not even correlation, let alone causation. They claim attributions to natural and anthropogenic outputs. A pox on both their attributions.
They claim to have shown the Before and the Subsequent, the B and the S. “Teased out…”. Gimme a break!
Not to mention they had to ignore sea level variability caused by the earths slow moving molten core.
SR: Please be kind to them (Fasullo and Nerem), as they have always relied on the kindness of strangers. They are experiencing a Blanche Dubois level of cognitive dissonance. Mann and his tree-ring-circus insisted that AGW was global, certainly not debunked by evidence of past “regional” warming, so regional stuff was for den1alists. So models did away with “regional”, only to observe that the globe still manifested those damn regional differences, and in SLR of all things! So how to explain it? Well, it’s human-caused, we know that, so let’s run the “global” models a few dozen times to find two things not designed for- the human factor and regional differences. I am certainly enjoying watching them squirm.
Would someone please explain to me how anyone could measure sea rises to the accuracy and consistency as suggested here, as needed to provide any credibility to such a theory, when the sea level is for ever varying from wave/wind actions, tidal actions etc.etc. and at various times!
Although Clark etal 2018 have shown that global mean sea level rise correlates with global emissions?
https://tambonthongchai.com/2018/09/14/cumulativeslr/
But how do you measure the global mean sea level when sea levels around the globe are continuously varying, to varying degrees at each location, for varying reasons such as winds, waves and tides and from satellites which can only measure one location every hour or so, and not necessarily at the same location next time round? Do they simply take all the measurements they have taken in the year and quote the average of all the satellites’ readings which, hopefully equally cover all areas of the seas with equal numbers of measurements in each area!
Peter Wilson – December 5, 2018 at 1:09 am
Pete W, …… I figured you knew, …..they measure the global mean sea level with 102% accuracy …….. the same way that they measure the global average near-surface air temperature with 102% accuracy.
NASA is like CO2, ….. it can do bout anything it wants to, and do it perfectly correct and accurate.
so its just a shame that to date there is no way to measure global mean sea level in a scientific meaningful way rather than a lick your thump and stick it up to see if its going to rain type of way .
‘Better than nothing ‘ is not a replacement for accurate and valid measurements.
It is very ironic, although totally appropriate, that “Fasullo” is an Italian translation of “Fake”. LOL
And according to Wiktionary, “Nerem” is a “first person singular” derivative of the Italian word “flaw” or “defect.” You know I actually just started wondering whether this was one of those fake papers submitted to peer reviewed journals, but I did a search and the authors look like real people.
Respectfully Kurt, I think you mixed things up and searched for “fasullo” again, as “nerem” is certainly not an Italian word, nor related with any of them
I checked again, and you are correct. “Nerem” is a Latin form of the term “neo.” One of the Italian synonyms of “neo” is “flaw” or “defect.” The Latin meaning of “neo” is “weave” or “entwine.” These were on the same page, so I mixed up the Italian meaning with the Latin meaning.
https://en.wiktionary.org/wiki/nerem
https://en.wiktionary.org/wiki/neo#Latin
Now I see, and you’re right. “Neo” is the Italian for “mole, beauty spot” and is indeed figurative for “flaw, defect”.
So we have a laughable paper filed by John Fake and Steve Flaw. ROTFL
I hope the IgNobel prize committee is taking due note.
I vaguely recall reading an article in National Geographic(??) about the rising shoreline in Sweden(??).
In this article the shoreline was rising about a foot per year due to isostatic rebound.
Does this “research” take into account this phenomenon? Where else is it happening?
Ice covered areas re-bounce.
Canada, US .
Blue arrows!
https://tidesandcurrents.noaa.gov/sltrends/sltrends.html
Everywhere that was covered by ice during the last glaciation.
And the ice also caused a “forebulge” outside the ice edge which is now sinking back, and is partly the cause of the sinking of the Eastern Seaboard. So in a way they are right. It is due to climate change, but it occurred about 12,000-20,000 years ago.
“Regional differences in sea level rise are influenced by where heat is stored in the ocean”
Not a word about land subsidence then. What a joke.
However they unwittingly show that this so-called thermosteric sea-level rise has no effect at coastlines, since practically no heat can be stored in the shallow coastal waters.
Must I be polite? This “study” is recursive idiocy. They look at their own data adjustments and declare that the trends (as such) will continue or worsen — never mind the laws of physics. These prophets of doom have no honor in my house — I lived in Boulder before it got Californicated.
The most amazing thing about this research is it is based on a new tool!
Who ever imagined they needed a new tool when simply lying about future projections/predictions seems to be working so well?
WUWT is obediently recycling every single warmist-alarmist claim, clearly working hard trawling the media to make sure they don’t miss any.
Did I miss the memo?
Is WUWT now a CAGW-compliant warmist blog?
Tasfay,
I think you have misunderstood the policy of revealing the lunacy that passes for UN promoted climate science/sea level alarm, by simple putting it into the public domain.
Anyone reading these endless pseudo scientific studies can see they are political first and scientific last.
It allows the rational minds among the readership to respond and challenge the science involved.
Clearly as we have seen time after time the simple open peer review this policy allows shows the false alarmist science is exactly that.
Long may the alarmists work get published for ridicule for that is what is now increasingly happening.
“Clearly as we have seen time after time the simple open peer review this policy allows shows the false alarmist science is exactly that.”
Better still it exposes the formal peer review process for the farce that it is.
Tasfay: Just stopped by? This site has (for the ~6yrs for me) posted warmist press releases without comment, allowing us to savage it. So, yeah, you are missing something.
Paul
I’ve been here a long time.
But every so often I say something really stupid and then change my name.
Models are great , you can get the result you ‘need’ wihtout the hard work in doing experiments or having to deal with being ‘let-down’ by reality . Plus you known they can used to produce the type of scary headline you known helps the grant applications no end .
So who cares if they are GIGO if they give you the ‘value added ‘ factor you need, and after all when you work in an area that is always pissing into the wind in the end none of it matters .
When your job is that of a professor who strives for things like research grants, and authorship of peer-reviewed publications, and when the things you are opining on are those that occur far in the distant past or future, or are otherwise incapable of being actually confirmed in a way that demonstrates you right or wrong, then in that wonderful world, theory . . . reality . . . what’s the difference?
Can the uneven sea level rise rates be interpreted in terms of the proposition that the rate of sea level rise can be moderated by reducing fossil fuel emissions?
https://tambonthongchai.com/2018/12/05/attenuate-slr/
“…regions of the world where seas have risen at higher than average rates — including the Eastern Seaboard of the United States and the Gulf of Mexico — can expect the trend to continue as the climate warms.”
Of course, because the reason relative sea level is rising faster on the Eastern Seaboard is that the land is sinking, which will continue whether climate gets warmer, colder or remains the same.
And you only have to look at a map to see that this has been going on for millenia. The Eastern Seaboard is a classic case of a sinking coastline with rias (drowned river valleys) and barrier islands.
Thanks be to god that the continental plates and the sea bed (ie Earth’s crust) are not moving!@#$%^&*
We are so fortunate to have such firm reference points!@#$%^&*
It’s like everything in Climate Science you just assume a value you like and call it a baseline, it doesn’t matter it is moving 🙂
When I started to read this piece, I thought I would bookmark it for insights into regional differences in SLR. At the end I discovered there was no there, there. Just like Oakland.
What a waste of a press release.
I’m curious how a model which did not accurately HINDcast temperatures, can be expected to accurately FOREcast seal level, using those same temperatures.
Even if it hindcasts properly there is still a very large and real probability it can’t predict very far ahead because it doesn’t really cover the underlying behaviour. That is why weather forecasts are only useful for 3-5 days ahead and it doesn’t matter how many models and computer power you throw at it. It is a fairly well known mathematical proof to show no matter what you do classical weather prediction models will fail at 3-5 days.
Ask a Climate Scientist for the predictive limits of their models if you want a bit of humour 🙂
Now, if they could just tie uneven weather to “climate change”.
Oh wait.
Their observations and their conclusions have nothing in common. They observed lumpiness of the Ocean surface….. Which then gave them poetic licence to program their climate activism into a Computer Model… Oops, sorry. “large ensembles”, probably because it sounds sciency, sophisticated an’ just a little bit French,
…. and Voila! Global Warming Ocean Catastrophe version 94.10… and because, “satellites”. It must be true.
I’m sick of these guys and their “Ensembles”. I prefer to call it a scam. It has less letters and is easier to type.
Are we accurately measuring the high tides in the Bay of Fundy?
Tides in the Bay of Fundy are over 50 feet in elevation. Clearly the land formation compounds the height of the tides there. Does that mean that an eight of an inch sea level rise would get compounded to be over an inch at the top of the Bay of Fundy tides? Is this happening?
I live in the forest in the mountains … I have nothing but questions on how sea level is derived to tenths of millimeters when stating sea level measurements.
Absolute sea level rise in relation to what? An absolute rise referenced to the ITRF that is itself only accurate within a couple of centimeters? Referenced to a geoid that is a model surface [with its own errors] referenced to the ITRF? An average of satellite altitude measurements from satellites whose orbital position is only known at best within centimeters? They are measuring a sea surface that is uneven over time and position. How do they use measuring and reference systems accurate to centimeters to derive absolute sea level within tenths of millimeters? Can averaging many measurements be any more accurate when they are measuring a property which varies with time and location?
Tide gauge sea level. Is it corrected for crustal motion with nearby MORS data or is it relative? NOAA isn’t much help with that at their web site. How much of the sea level rise detected by tide gauges is due to local land subsidence? The East coast and Gulf coast of the US are known to be subsiding. Is the subsidence being removed in order to determine absolute sea level rise? How can they derive tenth of millimeter accuracy with gauges that are not accurate to tenths of millimeters?
Isn’t the measured sea level change they are reporting somehow at least an order of magnitude better than the measuring systems they are using to derive sea level?
Is any of this conflating precision with accuracy? What is the estimated error in the accuracy of the sea level measurements?
back to the forest …
Regional differences in rate of sea level rise? OK, yes, the data show differences, but given the following basics from physics and hydrodynamics and aerodynamics:
1) Universal sea level theoretically is the same the world over – its gravity
2) Universal sea level rate of change theoretically the same the world over – again, it’s gravity
3) Any differences in absolute sea level must be due to other factors, including measurement errors, local subsidence or uplift, and the effects of sea currents, sea bottom profiles and land obstructions on the free flow of water between seas, and prevailing winds that create a geostatic energy difference between two points on the sea surface
4) Any differences in rates of change in sea level between any two points on the sea surface are also due to the same factors listed in point 3) above.
Funny, but the sea level alarmists never talk about any of these very basic scientific factors … indeed they ignore them altogether.
Now tell me again who are the “science deniers”?
This is exactly it. There’s a huge amount of variability in global sea level – many metres difference. It amazes me that studies such as these nod to regional differences but, despite the knowledge we have regarding gyres, effects of wind, isostatic/eustatic movement and so on the results *still* refer to a ‘global’ sea level (and ditto ‘global’ temperature change. I have noticed too, there is a propensity to attribute blatant anthropogenic change due to less-than-ideal land use to ‘climate change’. So you have land which is compacting due to housing and water extraction… But it’s still because climate change. This is what concerns me: instead of a thorough assessment, future assessments will basically be: “this issue is occurring because climate change”. The end – totally ignoring important facts that we can truely learn from – and more to the point – mitigate against, rather than throwing money down the black hole of trying to control the climate when we can’t even control relatively simple things like rivers and landslides (rolls eyes).
“… the global rate of change — about 3 millimeters a year and accelerating…”
While there may have been a recent increase in the rate of change, the proof of acceleration is not in evidence. They are essentially making a forecast, which shows their bias.
Is anybody going to bother to point out that there are thousands of “scientists” who think the sea level can rise differently in different places?
It is the most idiotic thing I have heard since someone claimed that CO2 caused climate change.
The effects of climate change are felt by all normal people on their own skin. It is therefore completely astonishing that there is such a discourse where skeptics are in the majority. This is a strong phenomenon that when we are all going to suffocate in the sea water, there will continue to be heated debates about the causes of climate change.
To summarize the conclusions of this study:
“Places where SLR has been slower than average, will continue to show slower than average SLR, and places where SLR has been faster than average, will continue to show faster than average SLR”
Would anyone have expected differently?
Yes of course, because physical law says equilibrium sea level should follow gravitational isobars. Therefore if you measure deviations from the equilibrium, you should expect subsequent measurements to come back the other way to restore the equilibrium. But these “scientists” appear to be missing these simple rules that Tom Sawyer would understand by instinct, duh.
Sea level is not the same everywhere. Because of the rotation of the Earth, sea levels on the western margins of the oceans is higher than that on the eastern margins, 1 or 2 feet or more. Winds influence ocean currents and sea levels. For example, during the southwest monsoon, the sea levels on the west coast of India rise 1 or 2 feet. Also, as others have said, deposition of silt by rivers will raise sea levels .
On two occasions I have been asked, ‘Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?’ I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question. — Charles Babbage
See, they apparently had “climate scientists” who viewed computer models as gospel even waaaay back then…and back then at the dawn of computing machines, Charles Babbage already knew the limitations. You’d think by now this knowledge would be pretty widespread and understood…but you’d be wrong!
Sorry wrong video. This one is much better…
What does this mean? Shift gravitational forces???
Uneven sea level rise is also influenced by ice sheets, which lose mass as they melt and shift the gravitational forces affecting regional sea surface height.
[??? .mod]
“Uneven sea level rise is also influenced by ice sheets, which lose mass as they melt and shift the gravitational forces affecting regional sea surface height.”
Good point. That would be the geoid, something not covered by the article and not even much by the comments. Although the physical Earth has excursions of +8,848 m (Mount Everest) and −11,034 m (Marianas Trench), the geoid’s variation ranges from +85 m (Iceland) to −106 m (southern India), less than 200 m total compared to a perfect mathematical ellipsoid. The oceans are not a bath tub with equal levels everywhere. As stated in the article, the oceans are ‘lumpy’. They are up to 200 M (640+ feet) differential elevation as measured to the centre of the Earth. If all the ice in Greenland were to melt, the meltwater would migrate slowly to the equator and finally be mostly offset on the opposite side of the planet from Greenland. Because of of gravitational forces of the mass balance of the ice sheet and the density of the crust, and a lot of other stuff.
The strength of gravity is not the same everywhere, because density (and therefore mass) varies throughout the planet. This is due to continents, magma distributions, mountain ranges, deep sea trenches, ice caps and so on. And everything is changing slowly relative to everything else, so the ocean level is ‘baked’ in to all this gravitational effect. If a perfect sphere were then covered in water, the water would not be the same height everywhere. Instead, the water level would be higher or lower depending on the particular strength of gravity in that location. That is why the ocean sea level is +85 M higher near Iceland relative to the centre of the Earth, (in part because of the Greenland Ice Sheet) and -106 M lower in S. India relative to the centre of the Earth. But you wouldn’t be able to tell with a spirit level. The Panama Canal is a good example, but perhaps more related to winds, tides and deeper and higher ocean temperatures, but some geoid effect and the Pacific Ocean is 2-3 feet higher than on the Atlantic side of the Canal.
Very interesting subject…hope I am beginning to understand it in some detail.
https://en.wikipedia.org/wiki/Geoid
And just when you thought it was safe to come out of the closet, CBC is reporting that climate change could wake Canada’s volcanoes.
https://www.cbc.ca/news/thenational/climate-change-could-wake-up-canada-s-dormant-volcanoes-1.4934504
“Natural shifts in ocean cycles — including the Pacific Decadal Oscillation, a pattern of sea surface temperatures similar to El Niño but longer lasting” —
Pacific Decadal Oscillation CAN’T last longer then ~ 6 years el Niño + 1 year la Niña
because el Niño is the DRIVER of the Pacific Decadal Oscillation despite the name.
Glad to get corrected where I’m wrong.