Guest Post by Willis Eschenbach
Gavin Schmidt, who I am given to understand is a good computer programmer, is one of the principals at the incongruously named website “RealClimate”. The name is incongruous because they censor anyone who dares to disagree with their revealed wisdom.
I bring this up because I’m on Twitter, @WEschenbach. You’re welcome to join me there, or at my own blog,Ā Skating Under The Ice … but I digress. I always tweet about my new posts, including my most recent post, Changes in the Rate of Sea Level Rise, q.v.
To my surprise, Gavin responded to my tweet, saying:
I responded, saying:
Now, to paraphrase Pierre de Fermat, “I have an explanation of this claim which the margin of this tweet is too small to contain.” So I thought I’d write it up. Let me start with the money graph from my last post:
Figure 1. 31-year trailing trends in the rate of sea level rise.
Is the sea level rise accelerating in this graph? It depends on which section you choose. It decelerated from 1890 to 1930. Then it accelerated from 1930 to 1960, decelerated to 1975, stayed flat until about 2005, and accelerated since then … yikes.
As I mentioned, until we have some explanation of those changes, making predictions about the future sea levels is a most parlous endeavor …
HOWEVER, Gavin wants to look at the overall changes, so let’s do that. Figure 2 shows the entire record shown in Figure 1, along with lines indicating the best linear fit, and the best accelerating (quadratic) fit.
Figure 2. The Church and White sea level record, along with best-fit linear (no acceleration, blue) and quadratic (acceleration, red) lines.
Now, this is what Gavin is talking about … and yes, it certainly appears that the quadratic (accelerating) red line is a better fit. But that’s the wrong question.
The right question is, is that a significantly better fit? When we have two choices, we can only pick one with confidence if it is statistically a significantly better fit than the other option.
The way that we can measure this is to look at what are called the “residuals”, or sometimes the “residual errors”. These are the distances between the actual data points, and the predicted data points from the red or blue fitted line. The line which is a better fit will have, on average, smaller error residuals than the other option.
Now, we can use a measure called the “variance” of the residuals to determine which one has the better fit on average. And as you might expect from looking at Figure 2, the variance of the straight-line residuals (no acceleration) is larger (80.2 mm) than that of the residuals of the red line showing acceleration (53.3 mm) … so the acceleration does indeed give the better fit.
But how much better?
There’s no easy way to answer that, so we have to do it the hard way. The hard way means a “Monte Carlo” analysis of the two sets of residuals. We create “pseudo-data”, random data which has statistical characteristics which are similar to the real residuals. Now, the residuals are not simply random numbers. Instead, they both have a high “Hurst Exponent”, which can be thought ofĀ as measuring how much “memory” the data has. If there is a long memory (high Hurst Exponent), then e.g. this decade’s data depends in part on the last decade’s data. And this changes what the pseudo-data looks like
So what I did was to generate a thousand samples of pseudodata which had about the same Hurst Exponent (Ā± 0.05) as each residual, and which on average had the same variance as each residual. Then, I looked at the variance of each individual example of the groups of pseudo-data, to determine how much of a range the individual variances covered. From that, I calculated the “95% confidence interval” (95%CI), the range in which we would expect to find the variance for that exact type of data.
It turns out that the 95% confidence interval of the variance is not symmetrical about the variance. It is larger on the positive side and smaller on the negative side. This is a known characteristic of the uncertainty of the variance, and it is what I found for this data.
So with that as prologue, here is the comparison of the variances of the two options, acceleration and no acceleration, along with their 95% confidence intervals:
Figure 3. Variance and 95%CI for the acceleration and no acceleration situations.
Here’s the thing. The 95% CI for each of the residuals encompasses the variance of the other residual … and this means that there is no statistical difference between the two. It may just be a random fluctuation, or it might be a real phenomenon. We cannot say at this point.
We can understand this ambiguity by noting that from the start to about 1930, the trailing trend line in Figure 1 shows a strong deceleration in the rate of sea level rise. We have no clear idea why this occurred … but it increases the uncertainty in our results. If there were a clear acceleration from the beginning to the end of the dataset, the uncertainty would be much smaller, and we could say confidently that there was acceleration over the entire period … however, that’s not the case. The trends went up and down like a yo-yo … and no one knows why.
Finally, let me caution Gavin and everyone else against extending such a trend into the future. This happens all the time in climate science, and it is a pernicious practice. If we had extended the decelerating trend back in 1930, we would have predicted a large fall in sea levels by the year 2000 … and obviously, that didn’t happen.
My own strong wish in all of this is that climate scientists should declare a twenty-year hiatus in making long-range predictions of any kind, and just focus on trying to understand the past. Why did the rate of sea level rise decelerate in the early part of the Church and White record, and then accelerate so rapidly? Why did we come out of the Little Ice Age? Why are we not currently in a glacial epoch?
Until we can answer such questions, making predictions for the year 2050 and the like is a fool’s errand …
My best to all, including Gavin. Unlike many folks on Twitter, he tweets under his own name, and I applaud him for that. In my experience, anonymity, whether here or on Twitter, leads to abuse. I also invite him to come here and make his objections, rather than trying to cram them into 240 characters on Twitter, but … as my daughter used to say, “In your dreams, Dad” …
w.
As AlwaysāPlease quote the exact words that you are discussing, so we can all understand who and what you are referring to.
PSāNote that I have not included all of the uncertainty in these calculations. Remember that each of the Church and White data points has an associated uncertainty. I have only calculated the statistical uncertainty, as I have not included the uncertainty of the individual data points. This can only increase the uncertainty of the variance of both of the conditions, acceleration and no acceleration.
Why didn’t I include the uncertainty of the individual data points? Work and time … the statistical uncertainty alone was large enough to let me know that there is no statistical difference between acceleration and no acceleration, so I forbore doing a bunch more Monte Carlo analyses which would show even larger uncertainty. So many interesting questions … so little time. Clearly, I need minions to give some of this work to … all the evil global overlords in the comic books have minions, where are the minions of Willis The Merciless? Or at least the educational equivalent of minions … graduate students … my regards to everyone, especially the poor overworked graduate students.
Surreal Climate.
+42
Politicized science only accept policy?
Real Climate only on an alternative, GIGO Earth.
More just mathematical incompetence.
Re Fig 1 say it is pretty clear at a glance that there are oscillating elements to the data of varying periods at the very least which is not to say there is no ‘trend ‘ element but that it is buried in the signal. Having oscillating elements one of the first things that can cause a problem is if the data set starts near a ‘trough’ or ends near a ‘peak’ or both, the point being that data which conforms to a pure sine wave that starts at a trough and/or ends at a peak will produce an apparent ‘trend’. The ‘trend is of course a construct of the limited data set and not the nderlying phenomenon being recorded.
I actually saw this dunderklumpen, high school level stuff up made in a peer (pal?) reviewed, published paper on sea level rise in Australia where it was readily acknowledged that the clearly apparent PDO effect was present yet they ( duuuhhh) forgot to prequality/filter the data accordingly.
Yeah, there is a real problem with limited duration data sets of data with oscillating elements. So what? Just grow up and deal with it ‘climate scientists’.
No wonder there are skeptics out there let alone deniers and no wonder there is a whole industry in ‘science ciommunication’ out there trurning that sort of utter crap into a SCARY HEADLINE!!
The paper behind this sort of eco schlock science weems to me to be one of those LPU’s (Least Publishable Unit), i.e. like a barrel of oil or a kG of Lithium the standard commodity unit bu which production is measured and also to wheich the market price signal (funding commitment) is attached (“oil is up $1.45 per barrel while Lithium is downalmost 25 cents per kG with the opening of the vast new mine in Chile. LPU’s are steady at about $2500 in non Ivy Leage institutions but down slightly in the prestige market, probably due to the movement in the Lithium price… and that is the daily market report… so its back to Trixie Twinkletooth for the Sport news… Trixie…”.)
apologies for all the typos. On an old browser without spell check…
At least we can make out the misspelled words from an old browser. With newer browsers with auto-complete turned on it sometimes reads more like gibberish that the occasional typo error.
I haven’t been blocked by Gavin yet, that might be because I haven’t said anything to him. I am blocked by Katharine Hayhoe and Mike Mann so, do I get a prize? A check from the Koch brothers? Anything at all?
Such blocking is now unconstitutional I understand. Better watch it!
Albert
I’d say the gold standard is being blocked by Hot Su (or whatever her pseudonym) is.
Or maybe Griff, but he may not have a blog; however, he doesn’t like female scientists and is worried sick about polar bears. Haven’t see him around in a while; maybe he’s up in the great white north feeding them.
A one off post to remind readers I have withdrawn from this blog – reasons being the standards have dropped, there’s a lot of paranoia and name calling and if I want to read right wing Republican nonsense I can go to Breitbart.
It goes without saying that I have read and utterly refute all comments made in recent months ascribing bogus views to me.
Hi to David Middleton – still reading your stuff – did you ever watch the new Star Trek?
If you have, why are you compelled to tell everyone you are. Just stop posting, Dude. If you feel the need to announce your decision, it screams of attention grabbing.
Personally, I would not want you to stop posting, even tho I disagree with a lot of your posts. We need diversity of views to advance knowledge. But, I respect your decision to withdraw. Fair winds and following seas.
Griff May 25, 2018 at 5:02 am
A one off post to remind readers that I’m overjoyed that you left.
However, it’s totally in character for you to come back to tell us that you’ve left … I’m told that Cher is on her seventh “Farewell Tour”, I guess you are simply emulating her …
w.
Saying Coke Brothers with correct spelling sends you to moderation. š
Unfortunately true Albert… WUWT?
Super Cereal Climate
The acceleration is during the satellite era –
The margin of error with the satellite is approx 1 inch (25.4 mm). At 3mm per year , it takes approx 9 years to even see if there is a trend.
Secondly, since the known measurement error is a systemic problem, margin of measurement error cant be corrected by averaging all the measurements.
Maybe statistics in climate science is different than actual statistics.
“Maybe statistics in climate science is different than actual statistics.”
Steve McIntyre and Ross McKitrick formally demonstrated this is apparently the case.
The plot also looks like it could be fit with a sinusoidal variation about a linear trend (i.e. about the line) and that would be more consistent with what we do know about the role of oscillations in the ocean-atmosphere system.
Joel: You could drop “apparently” and ring the bell!
These “accelerating sea level rise” discussions remind me of a story about Dizzy Dean, pitcher during the thirties. Reporters loved him, always good for a wisecrack with thick layer of country relish. Seems a scientist was quite certain that a baseball did not actually “curve” when thrown, so a “curveball” was in fact an optical illusion. A reporter told him this, and Dizzy snapped back that the scientist could stand on one side of a tree; Dizzy would go sixty feet six inches t’the other side of the tree and “wop him up side the head with an optical illusion.”
Here, Gavin, Hansen and the CliSci club are dead certain, as they wave another chart, that sea level rise is accelerating and dangerous. Meanwhile, us country bumpkin skeptics have no difficulty finding 500y, 1000y, even older roman structures built by the seaside, that are still at the same relative level. Even in the “accelerating” era, when small islands should be shrinking and disappearing, there’s hard physical evidence some are growing. The physical evidence should “wop” Gavin “up side the head.” Any day now.
To many “scientists”, if the science can’t describe it, it didn’t happen.
They couldn’t figure out how to make a baseball curve, therefore baseballs don’t curve.
The science is perfect, that data is flawed. (Where have I heard that before?)
BTW, it was only a couple of decades ago when they finally figured out how a baseball curved.
If I remember correctly, the spinning baseball causes the air immediately above the baseball to spin with it.
On the side of the baseball where the surface is moving in the same as the baseball itself, this spinning air collides with stationary air and causes a high pressure area to build. On the opposite side of the baseball, the spin is pulling air away, creating a low pressure area. It’s these high and low pressure areas that curve the ball.
MarkW May 25, 2018 at 6:46 am
To many āscientistsā, if the science canāt describe it, it didnāt happen.
They couldnāt figure out how to make a baseball curve, therefore baseballs donāt curve.
The science is perfect, that data is flawed. (Where have I heard that before?)
BTW, it was only a couple of decades ago when they finally figured out how a baseball curved.
Make that a couple of centuries!
It’s called the Magnus effect (Magnus force)
First described by Isaac Newton regarding the motion of tennis balls in 1672. Robins used it to explain the deviations of musket balls in 1742.
paul courtney May 25, 2018 at 5:50 am
Meanwhile, us country bumpkin skeptics have no difficulty finding 500y, 1000y, even older roman structures built by the seaside, that are still at the same relative level.
Also plenty that are at a higher relative level, Harlech castle comes to mind, and at lower levels, temples below sea level off Alexandria, Egypt.
Phil. May 25, 2018 at 2:01 pm
Also at lower levels, ā¦ā¦. homes, stores, pubs and brothels below sea level off Port Royal, Bahamas.
I believe much of Port Royal slid down the deep trench into the sea because of a nearby earthquake, liquefaction of sand beneath, and a tsunami. Bad day to be an English pirate in port.
Oddly climate ‘scientists’ do have a habit of avoiding involving those who are actual experts in statistics , a fact which has even come out in reports that have white-washed CRU and Mann .
Perhaps they are worried that they ‘only want to find something wrong with the data ‘
Its like the cleverest man on the planet, Dr Brainio, who knew everything about everything. But he would only discuss physics with the pope, and he would only discuss religion with a physicist
Here’s the solution for Gavin & the gang: graph the past 168 years (1850-2017) with a 168th degree polynomial with a couple free constants. Isn’t that more or less (ignoring data manipulation) [how] climate “models” work?
Yes. That’s just about what I had to do when I ran an analysis of quality ground stations some years ago, to get anything but a straight line trend, which, by the way, showed no warming or cooling. To get anything else, I had do a sixth-order curve fit – and that, quite inconveniently, showed a very mild cooling (as of 2002). Made for an interesting presentation in a statistics class. (I like hitting people with the “what NOT to do” kind of presentations. It tends to make them think about what they are doing, instead of just applying whatever tools happen to be laying around.)
Joe
“The acceleration is during the satellite era”
Would the same apply to temperature?
Regards
The tide gauges have been showing 1.4-1.6mm ish rise. When the satellite measurement was introduced in 1993, it was showing 3.1mm ish. while the tide gauges continued to show the 1.4-1.6mm range of rise. When the climate scientists noticed the two different measurements showed parallel lines, the readjusted the early years to match the tide gauges, which had the effect of showing the acceleration.
Joe, I think that you will find that upon the introduction of Satellite data that the Seal Level was shown to be dropping.
Funny how that European Satellite sudddenly malfuntioned and the data was no longer used.
”Maybe statistics in climate science is different than actual statistics.”
I think you’are statistically correct,…….
Gavin Schmidt works with Michael Mann? Wow. Now this posting takes on a whole new meaning. They both used the same data manipulation tactic. Thanks for the info Willis.
Multiple Sources Now Confirm; Climate Data āAdjustmentsā are Obvious Fravd to Anyone Choosing to Look
https://co2islife.wordpress.com/
And under James Hanson.
Who’s Hanson?
Wow. And up and until this very moment I thought tree rings were a valid proxy for sea rise.
Only when the rings are above each other on the OUTSIDE of the tree.
William Connolly was never in academia since earning his doctorate as far as I’m aware, Since leaving Oxford he worked for the British Antarctic Survey.
interesting info on connolley, explains some of the dross that passed as “climate science” that came from some bas expeditions, including the apparently quietly forgotten first discovery of anthropogenic co2 in ocean water. when the researcher was asked how the human oceanic co2 was identifiable from the naturally occurring upwelling co2 in the region sampled the answer was no reply. i should still have the email somewhere.
if western taxpayers were aware of the complete and utter meaningless dross (even much of the “correct” stuff) their taxes funded i would like to think there would be a riot. unfortunately as i often say, the dumb kids of the great and the good need something to do, they can’t all be diplomats.
Since the effects of CO2 AGW were [not] happening until 1950 on the global system, then the prediction of SLR acceleration due to said hypothesis is false, and the hypothesis is rejected in favor of the null hypothesis.
And the null hypothesis is that mechanisms of natural variability account for the data seen.
If sea level rise is a artifact of temperature…..then there should be about 2 decades of no sea level rise
That sorta messes with their whole theory…and decouples sea level from temps
shhhh, Latitude,
don’t tell anyone, but it’s hiding in the deep ocean. I have it on good authority from Top gub-ment scientists.
…I don’t think…..they think these things through
If sea level rise accelerated…when temps flat lined…..messes up their entire game
err no. sea level rise is A. a lagged response. B. the result of multiple variables.
not just temperature. duh.
I am flabbergasted. Mosher actually had a (no doubt momentary) connection to the real world.
Steve M.
But temperature is the only variable that GHG theory affects.
– Cryosphere ice mass loss prior to 1950 donāt count.
– And there is no lag in water temperature-density response.
– Finally, Pumping fresh water ground water from big aquifers unfortunately did accelerate in the 2nd half of 20th Century. US Ogalla, Mid-East, Asia, all pumped furiously to push arid lands agriculture. Surely thereās a hidden SLR component there no one can quantify.
Sea level hasn’t risen. I t has got deeper to hold all the extra heat.
Sea level rise is a lagged response? Water gets warmer and then…waits to expand?
“Sea level rise is a lagged response? Water gets warmer and thenā¦waits to expand?”
Well obviously….otherwise it wouldn’t fit global warming theory…. 8-/
It takes a few months for water from some of the melting glaciers to make it to the sea.
It does presumably take a while before meltwater or LOES-snowfall at one end of the globe affects water levels at the other end. But any change in forcing which affects sea-level trends should immediately affect the rate of sea-level rise/fall, somewhere. That is not “a lagged response.”
Of course it takes a long time for ice to melt, or for snowfall to build up, so there’s a long lag before the cumulative total effect on the level of the ocean is felt, from a change of weather conditions. But there’s no significant lag for the effect on the rate of change in sea-level.
Put a block of ice in a glass pan, on the counter in your kitchen. Watch it for a while and you’ll see that it is slowly melting. Then move the pan & ice into your microwave oven, close the door, and turn the power on. You’ll see that, even though it may still take a long time to melt all the ice, when you turn the power on the rate of ice melt increases immediately. There’s no lag before the rate of ice melt accelerates.
What’s more, even if there were some unknown mechanism that could cause a lag in sea-level response to a change in forcings, surely we should have seen the response by now. CO2’s “greenhouse” climate forcing has increased every single year since precise measurements began in 1958, yet there’s still been no significant, sustained acceleration in the rate of sea-level rise, detectable in the measurement data from any of the longest, highest-quality, coastal sea-level records.
Here’s the forcing (note the log-scale):
http://sealevel.info/co2_log_scale_1895-2017_height75pct.png
Here’s the (non-)effect of that forcing (at tectonically stable mid-Pacific location with a particularly high-quality measurement record):
http://sealevel.info/1612340_Honolulu_2018-05_noaa.png
Do you think you can see any significant effect?
If you think you do, maybe new glasses would help.
joelobryan May 24, 2018 at 10:00 pm
“Yeppy”, and that long duration of furiously pumping fresh ground water from big aquifers causes āland subsidenceā ā¦ā¦.. and vast areas of āland subsidenceā will cause sea level rise.
And worse, worse, yet, ā¦ā¦ furiously pumping fresh ground water from big aquifers also causes āland inclinesidenceā, ā¦ā¦.. and the āproof is in the puddingā, ā¦.. to wit:
Yours Truly, ā¦.. Eritas Rabuf
…and here the IPCC’s AR5 SP1 says CO2-AGW effects on SLR didn’t begin until 1970.
http://i68.tinypic.com/2a0g7kx.png
Even more reason to reject the AGW-SLRacceleration hypothesis based on the data.
What is ‘an incidence of high sea level’? They are kidding, right?
Crispy,
SLR is of course in mm/yr range. While tides are in meters/ day range.
Thus the effect of SLR is only seen at high tides, king tides, spring high tides etc. Thus a few millimeter more on top of a 1 meter+ high tide is when āextreme high tideā effect can be manifest.
And the noisy nature of measurements means the ffect cannot be actually robustly seen for several decades, meanwhile SLR declines of AMO/ENSO etc are dominate.
Very messy to call to the science settled.
So there is apparently this relentless and remorseless sea level rise, like The Blob, coming to get us. It manifests itself particularly during high tides and storms. And then there is this terrible destruction of corals that NEVER happened before horrible man and his CO2 hit the air. But, coral bleaching is a result (partially) of LOW sea levels which manifest during tropical highs and particularly low tides.
So why doesn’t this rising sea level thingy compensate for the low sea level coral thingy? I call B.S. And not for the first time.
Is having a high Hurst exponent the same sort of statistical entity as red noise? I am more than a bit deficient in math.
From what I understand, a high Hurst exponent implies serial autocorrelation, so yeah, red noise.
Indeed, ned noise includes high Hurst exponent datasets
w.
who’s ned?
š
Gggrrrrr-ratta: …AGW weren’t happening until 1950 onward….
A little bit earlier in NZ, apparently:
https://paperspast.natlib.govt.nz/newspapers/ROTWKG19120814.2.56.5
GOAL(sic) CONSUMPTION AFFECTING CLIMATE.
RODNEY AND OTAMATEA TIMES, WAITEMATA AND KAIPARA GAZETTE, 14 AUGUST 1912
They are stating that 2,000,000,000 tons of coal are creating 7,000,000,000 tons of CO2 which is rain=sing the Earth’s temperature.
“The effect may be considerable in a few centuries.
One can look at actual sea level data on PSMSL.org (http://www.psmsl.org/data/obtaining/map.html) for world wide data or the NOAA site (https://tidesandcurrents.noaa.gov/sltrends/sltrends_us.html) for just the US. I have checked each of the 11 US sites for which data goes back 100 years or more. None show acceleration. None whatever. Someone else can go through the worldwide PSMSL data.
Perhaps this observation is just more American exceptionalism?
Ahhhh – Gavin demonstrates the practiced art of sophistry, by offering a distinction without a difference. A wise person addressed this human flailing-and-failing many years ago, with the question “And why beholdest thou the mote that is in thy brother’s eye, but considerest not the beam that is in thine own eye?”
Nice factual response, Willis.
Willis, how accurate do you think global sea level measurement was 50 or 100 years ago? I find it just as puzzling as declaring a global temperature from the same era.
I often find it amusing how sometimes the younger generations underestimate the capabilities of those that have come before. If you ever get a chance to visit a museum containing antique scientific instruments, marvel at the skill and workmanship of the instrument makers. Consider the clever design and engineering of the purpose-built instruments.
It has been said that people did not have computers then, so they had to think.
Sea level 50 years ago?
50 years ago NASA was putting men on the moon.
Your right they show considerable skill , for the time , but that does not change the fact that despite this skill they could not get the type of accuracy which is now claimed for their measurements.
Your see it is science 101 that to known something you need to measure it , and to measure it you need the correct collection methods to justify what you claim be measuring .
And what in practice do we have, well the use of ‘magic tree rings ‘ and other proxies is a dead give away that in reality it is often ‘better than nothing ‘ and when you start to look at the range and scale of measurements you see large areas with nothing and some with little , 3 thirds of the planet is ocean but that is covered by only about 3,000 buoys , even land based systems are a tiny number of what is actually required if you where following the principles of good experimental design.
And what is supposed to make up for this ‘ well that’s ‘models ‘ often classic GIGO the best part of them is the way in which you can get the results you ‘need ‘ by changing the parameters to put in , so you never have to worry about not finding the ‘correct results ‘
Its odd that despite all the money spent and the claims of most important event ‘ever ‘ the state of the systems used to providing the actual data has hardly changed over the years and hence the need to so often grab at ‘better than nothing ‘ which is then sold as ‘unquestionable truth ‘
Yes, but. In the climate game, one of the key measurements is daily temperature readings from locations all over the world and ships at sea. Now, did they have verniers on every thermometer? Did they use them when making readings at night? Did they use candles or oil lamps to read thermometers at night? Did they avoid breathing on the thermometers? In extreme conditions? How many times did the attendants at some remote station just make up a number instead of going to the outside thermometer late at night?
Remember the key claim of the warmunists is that the earth’s average sat atmospheric temperature close to ground level has gone up over the last 150 years about 0.9 degrees. Is that inside or outside of the error bars of their data?
@knr;
In this specific case, tide measurement has not advanced a whole lot from 100 years ago. You can be pretty sure the tidal measurements then are about as good as they are now.
They could get very accurate readings. What they could not do was subtract things like land rising or falling.
Which they had no way of measuring.
Walter Sobchak, do not discuss error bars. Oh, Lord have mercy do not bring them up. While you are at it, do not discuss confidence intervals or confidence levels either.
That would shine a light on the cockroach circus that is global temperature average. Can’t have that.
KNR – I think you over estimate the quality and capability of today’s instruments. We can pretend to measure to hundredths and thousandths, but in actuality, that is a pretense. Just like using a slide rule. You can pretend that you can’t get significant results, but the careful user can get a lot closer, and the margin of error is less that you might think. No, you can’t get 10 decimal accuracy, but can you REALLY get even 3 decimal accuracy with most modern equipment when it comes to measuring? I think you can pretend that you can, but every component within the system has a margin of error, and there is no way of knowing if they cancel each other out or only partially or not at all. I really question it past the first decimal in most cases, and you can visually estimate to that on older equipment.
Are we that much better now? Ship intake temperature readings supplanted by digital measurement floats that are determined to be faulty and in need of adjustment to the extent that they go back to sea water intake? That’s a joke! Satellite temperatures that have to be corrected for decaying orbits?
It seems to me there is always something wrong with the measurements. Another sign of a Bernie Madoff style hoax. Nothing that anybody can quite pin down. Like Michael Mann’s math, it doesn’t add up.
Ossqss, the answer is, sea level measurements 100 yrs ago were as IN-accurate as today’s. Scientists can only measure the sea level in any location on the coast to a very rough guesstimate. The fact our oceans change level constantly due to the motion of the moon makes any claims to know the sea level of the whole planet problematic, let alone the rate at which that level is changing. Then we can add in the effect of gravity creating huge lumps in the ocean above submarine mountains, submarine volcanoes creating hot water bulges, and continuing isostatic rises & falls of various coastlines as a consequence of the ending of the last glacial period. Lastly, there is the effect of the wind, which makes even daily low & high tide calculations estimates that only approach accuracy on a windless day.
I challenge all the expert such as Gavin Schmidt to provide a true measure of the sea level in Labrador’s Bay of Fundy, & ask them to prove it by standing at that level for 24 hours.
Please do not leave out orogeny that is for instance raising the US West Coast
Ray, We are well aware that Canada has problems with some matters of Provincial jurisdiction, but our geographical features are mostly pretty well agreed to and their boundaries fixed. That’s why I am puzzled as to why you moved the Bay of Fundy from Nova Scotia and New Brunswick to the Province of Newfoundland and Labrador.
Can we have it back please (I live in New Brunswick)? The Bay of Fundy, I mean.
Tony.
Just sayin,,,,,,,
Ha, it appears I became a youtube! I guess it is better than an Alexa or Tesla! LOL
So in 150 years, sea level has risen by 250 mm, or about a foot. Wow, be very afraid! But of course the fear is in the extrapolation of that quadratic equation for the next 100 years. Come in Al Gore with another scary video.
Use of logic informs one of how the Alarmists work, and how to proceed.
They use the “D” word to describe those skeptical of their future climate changes and SLR acceleration scenarios. It is a clear allusion that “d”-enier is also likely dismissing past events as fictional, such as the WW2 Holocaust, or the moon landings.
Use of logic says that past events leave data and evidence. They can be proven. Thus to “d”-eny them is the sign of an idiot.
But future events have not happened, and are speculative if there is no past data to support them. The alarmists of course claim the coming AGW is going to be unprecedented in the last some-odd million years.
This is much different than someone “d”-enying that the sun will rise in the east tomorrow. It has risen in East for the last 4.5 Gy, and it did so today, so with very strong likelihood it will tomorrow too. Anyone who “d”-enies the sun will rise in the east tomorrow can be taken as an idiot with certainty.
Thus the claims of the CAGWs always lies in the future. And with so many failed AGW related predictions to date, the better bet is they will fail to when that brutally uncaring “about human prognostications” calendar date arrives. The best advice is to do nothing related to the claims of AGW.
The fact that they must resort to such advocacy tactics, such as the 97% lie, shows how weak to nonexistent is their at best unsettled “science”.
That is the problem they are having selling the whole sea level drama is the problem is in 100+ years. It’s of no real danger to life so they have to sell a story of future cost. However people aren’t stupid the infrastructure will all have been replaced in a hundred years anyhow lots of it multiple times. The rate of change is so slow it’s never going to be a problem.
There own graph tells the story look at the level in 1850 or whatever that is supposed to be, look at the level today. Apparently the change is 200mm in that 150 years and what did we do about …. absolutely nothing. The rate might be slightly higher for the next 100 and 150 years and what do we need to do about … absolutely nothing.
Does he maintain the site on NASA time?
Yes. Just one reason out of many why he long ago should have been fired.
“When we have two choices, we can only pick one with confidence if it is statistically a significantly better fit than the other option.”
err. wrong. There is nothing magical about 95%. You choose the quadratic fit, you report how much better it is. There is no law of science or math or logic that dictates 95 percent. We can always pick one and report our confidence. The best fit is the best fit regardless of your confidence. However, thank you for debunking all the folks who are certain there is no acceleration, those who are certain the linear fit is best.
Mosh, you would know this
There’s no lag in water expansion to temperature.
How did sea level rise accelerate…when temps flat lined?
if it were only due to temperature there is a lag. but its not due to only temperature
“How did sea level rise accelerateā¦when temps flat lined?”
Could be because more warmth is absorbed by ocean, causing them to expand despite minuscule temperature rise (too small to be observed), instead of warmth going in atmosphere causing its temperature to rise.
Temperature is very bad metrics (*). Heat (= energy) should be used instead.
I am not saying this is happening. Just that it could. AGW theory doesn’t imply positive correlation between surface temperature and sea level rise, as they somewhat compete for the extra heat (postulated).
(*) promoting such a bad metrics is one of the reason making “climate scientists” no scientist at all, in my eyes
Steven Mosher May 24, 2018 at 3:12 pm
Mosh, it appears you missed the part where I said you can only pick one WITH CONFIDENCE if it is statistically significantly different. Sure, as you say, you could set your p-value to 0.25 or 0.50 if you wish … but you can’t have much confidence in that, can you?
And as to whether there is or is not acceleration, in the historical period covered by C&W there has been deceleration, acceleration, deceleration, steady rise, and most recently acceleration. Perhaps you think that adds up to “acceleration” … I say it adds up to not much, and that we also don’t understand it at all.
In particular, since the alarmist claim is and has been for thirty years that increasing CO2 is causing catastrophic acceleration, I’d say that claim is disproven. There is no correlation between the steadily rising CO2 levels and the deceleration, acceleration, deceleration, steady rise, and most recently acceleration of sea level rise …
Regards,
w.
Well said… Without the mechanics of how it occurs, it just isn’t possible to predict what will occur – you can only extrapolate from the known data and flip a coin.
In this case, the sea level’s rising is likely due to many interconnected mechanics (nature is messy, not organized into silos for our convenience) and so a simple curve fitting will likely never work well.
you still have confidence, albeit not at the arbitrary level of 95.
the level of confidence required is a pragmatic decision. only the dopes here would confidently assert that the data showed no acceleration with certainty.
a betting man would choose the acceleration fit…and give odds.
the fool would bet against it.
Steven Mosher May 24, 2018 at 6:30 pm
True. It’s also true that only the dopes here would confidently assert that the data showed acceleration with certainty.
I’m a betting man, and I wouldn’t bet either way … too much uncertainty.
My best to you, your posts are always interesting, always glad to see your name in my email.
w.
Steven
“a betting man would choose the acceleration fitā¦and give odds.
the fool would bet against it”
And that’s why most betting men are broke! They see the trends they want, whether they are really there or not and more often than not it takes a [boulder] to the head to to convince them they were wrong.
@Mosher
That sums up the difference between Climate Science and Real Science.
You are willing to take bets and want everyone to change there lifestyle and hand over cash.
You are an activist and there is nothing scientific in your answer.
Mosher said….
“the level of confidence required is a pragmatic decision. only the dopes here would confidently assert that the data showed no acceleration with certainty.
a betting man would choose the acceleration fitā¦and give odds.
the fool would bet against it.”
This, Mr. Mosher, is a poorly thought out statement. There is a reason for confidence levels, Mr. Mosher. As an engineer, I can tell you that there is a reason why we use them, Mr. Mosher. In the business world, as in every aspect of life we must make decisions on relevant data, so we look for a certain degree of confidence in our data. Data is easily misinterpreted, Mr. Mosher, because we have implicit biases that influence our decisions. Depending on your bias you WILL tend to interpret the data the way that fits your desire. The reason we have confidence levels and p scores is to make us think about our biases before we make a decision.
You are partly right, Mr. Mosher. No one should confidently assert that the data either shows or does not show an acceleration. However I can confidently assert that I am not sufficiently confident yet to think that you are right. The nice thing about acceleration is that it is a change in the rate of change. Give us another 50 years of data and then we can acknowledge acceleration…or lack thereof.
P.S. I use someone’s name often when I am sufficiently irritated. If it makes you feel better to think of me as rude today, you can just trade out your name for some appropriate put down. Like the one you use…idiot.
Mosher writes
A betting man might ask a few questions of what it would take for SLR to accelerate. SLR Acceleration implies increasing rate of energy sequested into the ocean to facilitate the thermal expansion and into the atmosphere to facilitate land based ice, melting. The only way that can happen is if the TOA radiative imbalance is increasing.
And for SLR to get anywhere near the dire predictions of multiple cm per year, the energy accumulation and hence imbalance needs to chage by an order of magnitude at least.
Does that sound like a good bet? Or is this a pedantic bet won by a small amount of acceleration for a few years only.
“No acceleration” is twitter-speak for “there’s been no significant, sustained acceleration in the rate of sea-level rise, over the last nine or more decades, detectable in the measurement data from any of the longest, highest-quality, coastal sea-level records.” Which is right.
Church & White have been down this “acceleration” road before. Twelve years ago they published the most famous sea-level paper of all, A 20th Century Acceleration in Global Sea-Level Rise, known everywhere as “Church & White (2006).” It was the first study anywhere which claimed to have detected an acceleration in sea-level rise within the last century.
(The paper failed to mention that all of the “20th century acceleration” which their quadratic regression detected had actually occurred prior to the 1930s, but never mind that.)
In 2009 they posted on their web site a new set of averaged sea-level data, from a different set of tide gauges. But they published no paper about it, and I wondered why not. So I duplicated their 2006 paper’s analysis, using their new data, and not only did it, too, show slight deceleration after 1925, all the 20th century acceleration had gone away, too. Even for the full 20th century their data showed a slight (statistically significant) deceleration.
My guess is that the reason they wrote no paper about it was that the title would have had to have been something like this:
Church and White (2009), Never mind: no 20th century acceleration in global sea-level rise, after all.
Correction:
“a slight (statistically significant) deceleration”
should be:
“a slight (statistically insignificant) deceleration”
I especially hate my typos when they invert the meaning.
“The paper failed to mention that all of the ā20th century accelerationā which their quadratic regression detected had actually occurred prior to the 1930s, ”
You mean deceleration stopped before thirties? True, that’s not actually a consistent AGW finding.
OTOH. publish or perish.
Mosh
Absolutely right. Look at the output of the 72 (or how many ever there now are – this is settled science, you know), and the real temperature (or as close as data manipulation can get to it) is way lower than the models. So, of course we throw out the 95% test.
/sarc (if needed)
PS: a few more years of this crap an we will have undone the Enlightenment and gone back to chicken bones.
we already have gone back to chicken bones, only they are computer-assisted, hence so much better.
paqyfelyc, since computers are becoming our new gods, your statement could not be more true.
What? The statement is entirely right, and it has nothing to do with what confidence level you use.
But if you think science isn’t about 95% or better, you are dreaming. Go and claim you have a found a new particle at CERN with 95% confidence. They will laugh you out of the country.
95% means there is a 1 in 20 chance the results are random, so unless you can get the result time after time after time (which you cannot with a time series from the Earth), then 95% is pretty much neh, and anything less than this is almost certainly random..
There is no law of science or math or logic that dictates 95 percent.
=======
It is 2 sigma. The standard of proof for climate science and the other social sciences. Real science insists on 5 or 6 sigma.
ferdberple May 25, 2018 at 6:04 am
There is no law of science or math or logic that dictates 95 percent.
=======
It is 2 sigma. The standard of proof for climate science and the other social sciences. Real science insists on 5 or 6 sigma.
No real science typically uses 2 sigma, the very speculative stuff like digging out the signal from a Higgs boson from all the noise is what requires 6 sigma.
Phil I hate to break it to you, but no-one will believe you at 2 sigma except in the soft science fields but really you can just speculate in those fields (hell knows I have read enough of those trash papers).
Not true, 2 sigma is widely accepted, as I said it’s only some of the more speculative physics that goes to such extremes. I’ve worked in ‘hard science’ for many years and never had any trouble getting my work believed (~100 papers).
Yes, Phil, 2 Sigma is right at 95%. But as someone who deals with 6 Sigma for quality and process control, I am not impressed.
There is a reason why many engineers question, remain skeptical, or barely qualify as lukewarmers on the subject of CAGW. The data is poor quality, the rationale is weak, the bounds are poorly defined, the weight placed on models is evidence of a lack of real information, and the biases are evident.
Actually I would like Phil to show me any theory any science fact of significance that we believe just on 2 sigma. What you will find when we overturned classical physics 100 years ago and the rise of QM we knew that most everything in science at that point was wrong and had to be checked again. The exception to the revolution was the biological sciences which largely went along unaffected (a situation that may not last).
Dealing with areas outside biology I have no issue that you can publish stuff at 2 Sigma but it will certainly not be believed unless it has multiple threads of proof. Even then it lives in a twilight zone that it is easily overturned unless it’s foundations can be dragged back to QM because if it is relying on classical physics.
There have been studies done like this one back in 2014 looking at what fields were actually using modern physics and which were using classical
https://arstechnica.com/science/2014/08/the-never-ending-conundrums-of-classical-physics/
It was hardly surprising that studies showing field advancement showed those using modern physics were the ones making large gains.
There are a number of areas QM is really pushing into at the moment probably the most significant to Climate Science studies is the area of thermodynamics in which there is large push to clean it up. The problem has become fairly obvious that quantum coherence need to be added to all the thermodynamic laws.
The initial thought were that there would be some strange cases at the small scale and at the large scale you would end up back at classical physics. That turned out not to be the case a number of big classical physics laws are under threat. In 2016 quantum heat was transmitted 1 meter thru a supercooled wire and measured as classical heat as a sort of final proof
https://www.nature.com/articles/nphys3642
The key point it rammed home was that heat will be able to violate many of the classical laws even on macroscopic scales by utilizing it’s quantum properties. The open question was are there conditions in nature where these violations may occur.
So at that point you may consider what is a 2 Sigma porof worth?
The oil industry routinely uses confidence limits of P90 and P10 for assessing possible in-place hydrocarbon volumes in exploration, prior to drilling. This gives a confidence interval of 80%, which is about +/- 1.28 sigma. (Incidentally, Shell uses P85 and P15, a 70% CI which is pretty close to +/- 1 sigma)
The oil industry seems to be quite successful and continues to make money. The choice of confidence limits simply has to go hand-in-hand with the economic decision making and risking in order for it to work.
So you want to cause huge costs to other people, re-work the entire world’s economy, based on forecasts that you only have 70 to 80% confidence in?
I’m sure glad they don’t use that standard in death penalty cases.
MarkW May 25, 2018 at 6:59 am
So you want to cause huge costs to other people, re-work the entire worldās economy, based on forecasts that you only have 70 to 80% confidence in?
Iām sure glad they donāt use that standard in death penalty cases.
Yeah that’s 1 in 12!
Phil,
No, it’s 12 out of 12. Death penalty cases have to be unanimous.
>>
Phil.
May 25, 2018 at 7:35 am
Yeah thatās 1 in 12!
<<
Only in a kangaroo court. It’s actually 12 out of 12, and the legal standard is beyond a reasonable doubt.
In civil cases, it drops down to 5 out of 6 (or 10 out of 12 if there are 12 jurors) and the legal standard drops to a preponderance of evidence. Most of climate science doesn’t even meet the standard for civil cases.
The actual standard in science (if you are to believe physicists like Richard Feynman) is 100% correct all the time. Since science is an empirical based system (unlike mathematics where the problem domain is defined beforehand) anything can be wrong. We were taught to question everything–even the basics. There was never anything such as settled science–that’s a political term.
Jim
Felix May 25, 2018 at 10:20 am
Phil,
No, itās 12 out of 12. Death penalty cases have to be unanimous.
Not everywhere I’m afraid.
Jim Masterson May 25, 2018 at 10:38 am
>>
Phil.
May 25, 2018 at 7:35 am
Yeah thatās 1 in 12!
<<
Only in a kangaroo court. Itās actually 12 out of 12, and the legal standard is beyond a reasonable doubt.
Not in Alabama, and only since 2016 in Florida and Delaware.
Missouri and Indiana allow the judge to impose a death penalty in the case of a hung jury, happened twice in the last 6 months in Missouri, one of those was 10-2.
No, there is always a third (or more) choice:
– Decline to bet at this time.
The Hippocrstic maxim
“first do no harm”
speaks volumes in few words.
That the demands for a policy decision are being made based on such ambiguous derivative analysis is telling.
The raw data and actual experience shows the value of the bet, the expected payback from the cost of the bet, is negative.
The focus on psychology and mamipulation to near obsession by the alarmists shoukd be a clue.
Been hearing of CAGW sea level rise doom intensively since about 1992, and I’ve been living beside the beach for the whole time, and anacdotally have noticed zero change in sea level.
That’s about all I or anyone needs to know, Mosh.
Total non-event, once ground-truthed.
Next.
Willis, I don’t have any problem whatsoever with your work here.
Since you seem to have the quadratic equation used for the plot, what are the coefficients? I suck at math and I don’t think I’ve actually differentiated an equation since about 1957. Certainly not since 1970 or so. But I think that if the quadratic is written as A*x^2 +B*x + C, that the acceleration is the second derivative which might well be 2*A. I’m guessing that turns out to be a laughably small number.
The real problem for Gavin is that with any acceleration term, if you’re going to push it out 20 years or so, you’ll soon see an annual sea level rise that’s truly ridiculous. The same thing is true if you try to back calculate from a 2050 or 2100 sea level rise of 3 feet. The numbers will not make any sense.
Another problem for Gavin et al., is NYC’s East Side Hwy was projected to be underwater as we speak.
Thanks Willis. Qualitatively I agree. This is probably processing noise.
OTOH, 60 microns/yt/yr is larger than I expected. As I said, I suck at math, so it’ll take me a while (months most likely) to think this through.
Javert — It was the West Side Hwy (12th Avenue) and the projection was the result of James Hansen (Gavin’s boss at the time?) firing from the hip on a radio talk show in the late 1980s. There was/is no data, then or now, to support the claim and Schmidt does sometimes distance himself from truly bizarre assertions. IIRC, Hansen has another decade to run on that “prediction”. But you’re correct, there’s virtually no chance of it happening unless “they” dam the Hudson River someplace near the southern tip of Manhattan or a sinkhole several km in diameter develops under Central Park.
Javert Chip May 24, 2018 at 6:32 pm
Another problem for Gavin et al., is NYCās East Side Hwy was projected to be underwater as we speak.
If you’re referring to Hansen’s 1988 statement it was the West Side Highway, which no longer exists, its successor has been flooded several times already. Also the statement referred to 2028 not “as we speak”.
Here’s a reference to its recent flooding:
https://www.dnainfo.com/new-york/20170505/midtown/flood-watch-penn-station-flooding#
That is rain Phil not sea level rise. To make a point lets take a town 188 meters above sea level.
This is Winton in Queensland 2 months ago.
http://www.abc.net.au/news/2018-03-06/winton-surrounded-by-floodwaters-after-biggest-rain-in-a-decade/9519812
I am sure those in Winton are terrified by Sea level change and started moving out.
LdB May 25, 2018 at 9:47 am
That is rain Phil not sea level rise.
Hansen said it would be ‘underwater’ didn’t say anything about sea level.
In any case it has been flooded by seawater as well as rain, still 10 years to go.
And yet we are talking about SLR Phil. Way to side step an argument. What is this? Kindergarten?
Phil. May 25, 2018 at 8:01 am
Javert Chip May 24, 2018 at 6:32 pm
Say what? That’s not true. The West Side Highway still exists and is used daily by thousands of cars. Here’s information about it.
Not by the sea level it hasn’t, and that was what Hansen predicted.
We’re now thirty years into a forty year prediction, so sea levels should be something like three-quarters of the way there … but instead, the sea level has only gone up a few inches.
Here are the details about the prediction, from WUWT of course …
Regards, to all,
w.
“Say what? Thatās not true. The West Side Highway still exists and is used daily by thousands of cars.”
Sort of. In the 1920s an elevated West Side Highway was proposed and quite a bit of it was actually built in the early 1930s. But it started to fall apart in the 1970s and was mostly torn down — I think because they feared it would fall on someone. However, NY9A which runs along the Hudson is generally referred to as “The West Side Highway”. Technically, it is The Henry Hudson Expressway, 12thAvenue, 11th Avenue or West Street depending on where one is. That’s all in Wikipedia if one digs a bit.
Don, here’s the analysis:
Coefficients: Estimate Std. Error t value Pr(>|t|) (Intercept) 8.539e+03 1.339e+03 6.379 2.19e-09 *** cht -1.042e+01 1.384e+00 -7.529 4.75e-12 *** cht2 3.083e-03 3.578e-04 8.615 1.00e-14 *** --- Signif. codes: 0 ā***ā 0.001 ā**ā 0.01 ā*ā 0.05 ā.ā 0.1 ā ā 1 Residual standard error: 7.349 on 147 degrees of freedom Multiple R-squared: 0.9877, Adjusted R-squared: 0.9876 F-statistic: 5921 on 2 and 147 DF, p-value: < 2.2e-16cht is the time coefficient, and cht2 is time squared. So using your terminology, 2*A is 2 * 0.03 mm per year per year. So each year the rate of sea level rise would go up by 0.06 mm.
However, extending that rate into the future would be just as silly as extending the deceleration from the start of the record to 1930 up to the year 2018 …
w.
Thanks Willis. Qualitatively I agree. This is probably processing noise.
OTOH, 60 microns/yt/yr is larger than I expected. As I said, I suck at math, so itāll take me a while (months most likely) to think this through.
OK, I’ve been poking at 0.06 mm/yr/yr a bit. It looks to be around a foot of additional SLR over and above the expected 13inches from SLR and GIA during the next century projected by NOAA for the Battery tide gauge. As I said, I agree with you that it’s likely not a real number. I’ll get back to you after I relearn enough integral calculus to confirm the answer.
On my sealevel.info site I have code to do linear and quadratic regressions for sea-level data, for arbitrarily chosen time periods at almost any tide gauge. E.g., at The Battery, using data from January, 1930 to present (through March, 2018):
http://sealevel.info/MSL_graph.php?id=Battery&c_date=1930/1-2018/3
As you tweak the parameters, the URL changes in your browser address bar, to be the URL which takes you to that graph. So when you get one you like, you can bookmark or otherwise save the URL.
(Note: beware of the “calculate using … end date” field: if you leave that field set to the default, which is currently a couple of years in the future, then when the data gets extended the graph produced by your saved URL will change.)
On the right-hand side you’ll see:
To calculate the effect of that acceleration, just plug in the numbers, in the equation.
The calculated acceleration is 0.00367 Ā±0.01720 mm/yrĀ²
An acceleration of 0.00367 mm/yrĀ² (the central value) for one century would increase the rate of sea-level rise by 0.367 mm/year.
The fact that the 95% CI is much larger than the calculated acceleration means it’s not even statistically significant.
One subtlety is that “rebase” date (“1974.12” in this case), which represents x=0. The physical significance of that date is that if you plot the least-squares best-fit quadratic curve, that’s the date at which the slope is the same as the slope for the linear fit. (If A=0, i.e., if the quadratic fit results in a perfectly straight line, I just use the middle of the date range.) Using that “rebased” x value makes it possible to have the same “M” coefficient in both the linear and quadratic equations.
To see how the quadratic diverges from the linear for some date, you can just plug in the numbers. For instance, if date=2100, then:
x = 2100 – 1974.16 = 125.84
Linear:
y = -52.366 + 3.083Ā·x mm = 335.60 mm
Quadratic:
y = -53.557 + 3.083Ā·x + 0.00183Ā·xĀ² mm = 363.39 mm
The difference is 363.39 – 335.60 = 27.79 mm = 1.1 inches.
You can also plot the linear and quadratic curves, with or without confidence intervals. In this example I’ve plotted both linear and quadratic curves out to 2100, and included a graph of CO2 (in green), but disabled plotting the confidence intervals:
http://sealevel.info/MSL_graph.php?id=Battery&quadratic=1&boxcar=1&boxwidth=3&g_date=1850/1-2099/12&c_date=1930/1-2018/3&lin_ci=0&quad_ci=0
It looks like this:
http://sealevel.info/8518750_The_Battery_1930-01_to_2018-03_linear_and_quadratic_to_2100_vs_CO2.png
I’m waiting for Nils Axel Mƶrner to comment on this. As far as I am concerned, he is the expert on sea level data…
Willis tweeted:
Hmmm, There are 1,200 plus PSMSL tide gages and Church and White tossed about 700 of them out in their study – mostly for being in the mouth of an estuary. Here’s the link to the C&W data page:
http://www.cmar.csiro.au/sealevel/sl_data_cmar.html
Scroll down to where the list of tide gauges is provided:
A list of the tide gauges used is available here (zipfile, 21,008 bytes)
Here’s a comparison of their findings to PSMSL tide gauges
http://oi49.tinypic.com/ab78d5.jpg
I don’t know why estuaries should skew things quite like that, but it does seem that way.
Somehow they found 3.2 mm/yr when tide gauges show about 1.8 mm/yr.
And for some reason, Church & White papers seem to be the Holy Grail for sea level. I have my doubts about that.
donāt know why estuaries should skew things quite like that, but it does seem that way.
Brackish water constantly changing in salinity and for major rivers like the Amazon a tremendous variance in flow and water temperature? And then there is all of the stuff a river carries and dumps into the ocean like mud and silt.
Steve, I didn’t say that C&W is the Holy Grail for sea level. I analyzed it because it is used a lot. Doesn’t mean that I think that it is accurate …
w.
Yes, Church and White is used a lot. If you do your own analysis, you can’t come close to duplicating what they claim. The problem is, your own analysis doesn’t have any standing in the eyes of the well established powers that be regarding climate issues.
The problem is I think, that tide gauges measure relative SLR, not eustatic SLR. But as soon as you start selecting gauges to try to get rid of anomalous values, you can get just about any answer you want within rather broad limits.
It’s sort of like Generally Accepted Accounting Principles. Three accountants apply for a job. Each is asked “How much is two plus two?” The one who is hired is the one who answers “What sort of answer did you have in mind?”
Church paper itself states:
The linear trend from 1900 to 2009 is 1.7 Ā± 0.2 mm yearā1 and from 1961 to 2009 is 1.9 Ā± 0.4 mm yearā1. Note the error estimates.
Gotta love the “pernicious practice” comment…
I also replied to Gavin’s tweet:
https://mobile.twitter.com/ncdave4life/status/999630918309556225
https://twitter.com/ncdave4life/status/999630918309556225
https://twitter.com/ncdave4life/status/999643028452200449
https://mobile.twitter.com/ncdave4life/status/999643028452200449
Stand by to be blocked then. Just like I was
I hope not. I walked with him for awhile and we had a nice, cordial chat about polar amplification mechanisms, when he came to town a few years ago.
Of course I’m blocked by Mann, but who isn’t?
Twitter hint #1: if you can’t view someone’s tweet because he’s blocked you on Twitter, then right-click the tweet link and “open link in incognito window” or “open link in new private window” or “open in new InPrivate window,” or similar. You won’t be able to post replies from that window, but you can still reply to replies that other people sent to the person who blocked you, by copying their tweet URL and pasting it back into your regular (non-private) browser window.
Twitter hint #2: If you want to post just a link to a tweet, use the mobile version of the twitter URL, like this (let’s see if this trick works):
https://mobile.twitter.com/ncdave4life/status/999630918309556225
If you want to WordPress to “in-line” a tweet,” with context, like it did mine above, then use the non-mobile form of the twitter URL, which is the same as the mobile version but without “mobile.” in front (something like this, if my trick works):
https://twitter.com/ncdave4life/status/999630918309556225
And if you want both, then post both versions (which is what I did above).
Note that you can post a link to a tweet from someone who has blocked you, and WordPress will still correctly “in-line” it. After all, Mann only blocks people, he didn’t block WordPress (if that’s even possible).
Good job, Dave.
It seems that, no matter where you focus on the issue of climate change, it’s difficult enough to definitively establish any effect at all, let alone a detrimental one, and the alarmism is based upon extrapolation of what, in any other arena, would be considered preoccupation with inconsequential increments.
Well said Joel
It’s a consequence of large uncertainty in the data.
Gavin got his job not because of any ability or scientific status , but because he was a ‘safe pair of hands ‘ who could be trusted to follow AGW dogma not matter what the evidence. And he has proved himself worthy of that trust , so why expect any other attitude to the one that has brought him fame and some fortune and at the same time has required so little effort or hard academic work?
Willis,
Perhaps a better argument could be made using the Akaike information criterion see https://en.wikipedia.org/wiki/Akaike_information_criterion
By including the acceleration term, although the fit is better the independent parameters increased by one. A test would indicate if this parameter adds further to the information gained.
By way of example, one can increase the fit to nth power, which will perfectly fit to data. But the information gained will not be there.
Another formal statistical method uses variance inflation factor (VIF) as the test. This is close to but not exactly the method you’ve employed. see https://en.wikipedia.org/wiki/Variance_inflation_factor
regards
ChrisB
Good suggestion. The information criterion is unbiased and rigorous.
+1
+1
Exactly my thought.
āI have an explanation of this claim which the margin of this tweet is too small to contain.ā ~ WE
Is suspect immortality for this utterance.
The natural world is replete with mathematical fits. Now plot the time of a leaf falling and its path to the ground. What? Impossible? Exactly.
Now, to paraphrase Pierre de Fermat, āI have an explanation of this claim which the margin of this tweet is too small to contain.ā ~ WE
Yeah it took a friend of mine 129 pages to explain it!
And, Pierre, my friend, the work is WAY above your paygrade.
Willis, no insult meant š
The climate according to Ken MacLeod :
Remember the asteroid that killed off the Dinosaurs? Now you would have suspected that the asteroid would have thrown up dust, blotting out the sun causing catastrophic cooling, would’t you? Not so! It caused Global warming, which killed off the Dinosaurs. The lesson we have to learn from this is, according to MacLeod, we are drastically underestimating the warming to come due to our evil ways and the wrath to come.
https://www.newscientist.com/article/2170015-asteroid-that-killed-the-dinosaurs-caused-massive-global-warming/
[Very localized global warming, of course. .mod]
w – Thanks for yet another very clearly expressed and explained article. One aspect of the statistics/logic interests me: Of Figure 3, you say “The 95% CI for each of the residuals encompasses the variance of the other residual ā¦ and this means that there is no statistical difference between the two.“. I am not in any way suggesting that this is incorrect, but I wonder if there is a more useful way (to us non-statisticians) of expressing it. What I observe is that in this example each datum point falls well within the 95% range of the other. But the conclusion would have been the same even if each had only just scraped into the error range of the other. So, it seems to me, “no statistical difference” is not really a flat zero in both cases, all it tells you is that 95% certainty has not been reached. In this case, it falls a long way short; in a “just scraped in” situation it would be very close to 95%. I wonder whether there would be value in calculating the %age error range which hits the other datum point exactly. In other words, identifying the statistical probability of a difference. I’m no statistician, so apologies if I’ve not expressed this correctly.
W, sure you know this. The various Church and White estimates are comparatively compromised by changing selection of tide gauges., so not strictly comparable. For general support of your otherwise excellent comclusions, see my previous sympatico guest post Sea Level Rise, Acceleration, and Closure at WUWT. Regards.
Thanks, Rud, and I have been following your work there.
w.
ristvan
Am I correct in understanding you to be saying Church & White used different sets of tide gages for different years?
I was blocked at unrealclimate long ago, for nothing really significant other than asking the wrong question or disagreeing a little bit. I think the scientific sceptics outnumbered the usual sheep so some of us had to go.
Once in a while I check the site for amusement, but there is not much to learn there.
You really can tell some things quickly at a glance. That is the point of graphs.
For someone who is supposed to be an accomplished mathematician, and head of a large government agency, he has a very tenuous grasp of reality.
Michael
It is not about scientific truth, it is about choosing someone competent enough to maintain the status quo after the previous leader. Someone who will reliably sing the same song with emotive conviction. That is why Gavin is in the role.
Regards
In truth, I know, ozonebust. My biggest outstanding objection to the Gavage is that he speaks with an English accent, and is giving the rest of us a bad name.
“who I am given to understand is a good computer programmer”
I was not at all impressed with the ModelE GCM code that has his name all over it. It’s a jumbled mess of spaghetti Fortran, poorly organized and poorly documented. The guts of the radiative transfer portions of the code, Radiation.f, has thousands of floating point constants baked into the code, many of which are poorly documented and many are not documented at all. Having managed code developers in the past, I can’t see how anyone would confuse this code with the work product of a good computer programmer, especially one developing models from which trillions of dollars in counterproductive and ineffective policy are to be based.
Got to stop hitting post so quickly, it should have read, “many of which are poorly documented and many are not documented at all”.
co2isnotevil May 24, 2018 at 6:31 pm
Fixed … I hate typos and un-noticed errors …
And I agree with you about the ModelE code, although I suspect that it was something that “‘jes growed” at the hands of many people. But there’s more.
A decade or more ago, I asked Gavin how they handled the question of the conservation of energy in the GISS computer ModelE. He told me a curious thing. He said that they just gathered up any excess or shortage of energy at the end of each cycle, and sprinkled it evenly everywhere around the globe …
As you might imagine, I was shocked … rather than trying to identify the leaks and patch them, they just munged the energy back into balance.
So I asked, how much on average, and at peaks, is the imbalance in the conservation of energy? … again I was shocked, this time when he said he had no idea …
I said that me, I’d put some kind of Murphy Gauge on that variable, something that would give me a warning if there was a sudden imbalance that was just being swept under the rug.
He acted like this was both unheard of and goofy …
All of which explains why I said I was “given to understand” that he was a good computer programmer …
w.
Willis Eschenbach May 24, 2018 at 7:28 pm
co2isnotevil May 24, 2018 at 6:31 pm
Got to stop hitting post so quickly, it should have read, āmany of which are poorly documented and many are not documented at allā.
Fixed ā¦ I hate typos and un-noticed errors ā¦
And I agree with you about the ModelE code, although I suspect that it was something that āājes growedā at the hands of many people.
A problem with any ‘legacy code’ that has had many authors and ‘like Topsy,just growed and growed’!
As I recall Hansen first referred to it in 83? I think they recently ‘bit the bullet’ and did a rewrite (ModelE2?), rather like Spencer et al. did with AUH. I think the new version is documented and available to anyone who wants to use it.
Phil,
“I think they recently ābit the bulletā and did a rewrite …”
Yes, but the rewrite is just the old code ‘upgraded’ to a newer version of Fortran. The logic, algorithms and comments are basically the same, although they did replace some of the spaghetti with while loops and case statements.
What they should have done is start from scratch and construct a new GCM in a more modern and capable language like C++. Most of it could even be written in Java with only the relatively small performance sensitive pieces implemented in C or C++.
I too used to be shocked by learning such things, such as how the enthalpy of vaporization of water varies by ~5% between the equator and colder latitudes, but the modelers just shrug it off and pretend it won’t make any difference.
They may, or may not, be competent computer programmers, but they are not not scientists as we know them, Captain.
That is merely a product of how climate ‘scientistsā both consider themselves, despite the counter evidenced, to be experts in everything while at the same time being very unwilling to collaborate with those who are experts, be it coding or statistics. And there is some sense to that, keeping everything in-house helps to ensure the āright results ā, while it makes it harder for others outside their āmagic cycle of conformation āto challenge these results.
And when as is so often is the case, you are a third rate academic, like Gavin, if a first rate dogmatists , that certainly makes life easier and merely forms part of the smoke and mirrors game played in this area.
I suspect a good programmer and fortran cap don’t very often come in the same person.
Any very old software becomes a load of cruft. You should use new tools and new programmerrs called software architects. They can select a language (R, C++, Python, Ruby…) and make the project testable, robust, and maintainable.
But none can fix wrong assumptions and existence of hand-picked parameters.
hugs says “They can select a language (R, C++, Python, Rubyā¦) and make the project testable, robust, and maintainable.”.
hugs, i strongly suspect that is exactly the opposite of what the current programmers want.
Hi Willis,
Will you be following your own wish and wait 20 years until making any more posts about your own climate
model? Can you explain why we are we not currently in a glacial epoch using your climate model? Making a claim that the temperature is likely to be the same in 20 years time as it is today is as much a long term prediction as any predictions claiming global warming. So you should be following your own wishes and stick to explaining the past.
Extensive glaciation begins in the northern hemisphere when NH temperature drops sufficiently low that winter snow survives summer melting (even at lower elevations as is much of northern Canada). The most recent NH insolation decrease produced by orbital variations has not been sufficient to drop temperature low enough, and that NH insolation is predicted to starting increasing in a few thousand years. So, no glaciation this insolation cycle. It probably takes a really large insolation decrease to initiate glaciation, such as occurred ~118 thousand years ago to begin the last glaciation.
donb
Are you sure about that. Now, sea ice at latitude 60 is NOT land ice between latitude 70 and latitude 60 north, but in both 2016 and 2017, for the first time in our recorded history (that sounds more dramatic than “since the satellite records began in 1979), the sea ice in the Bering Sea and Sea of Okhotsk remained frozen though all of August, and all but 3 days in September. Further east, the sea ice in the S=Gulf of St Lawrence remained frozen many weeks longer than ever before, and the 2016-2017-2018 trends in the Hudson Bay are strongly positive (compared on a day-by-day basis.) Now, the all time high sea ice levels of 1980-1983 remain records. But isn’t it remarkable that lower latitude sea ice – where many times more sunlight is reflected than up north above 70 north – 80 north latitudes – is increasing now?
It has been shown that glaciations depend on decreasing obliquity, not precession-associated decreasing northern summer insolation. And obliquity will continue decreasing for another 10,000 years. So, yes glaciation this obliquity cycle unless alarmists are correct about both COā effect and COā long residence in the atmosphere. For what is worth, I think they are wrong on both.
RACookPE1978 May 24, 2018 at 7:34 pm
Are you sure about that. Now, sea ice at latitude 60 is NOT land ice between latitude 70 and latitude 60 north, but in both 2016 and 2017, for the first time in our recorded history (that sounds more dramatic than āsince the satellite records began in 1979), the sea ice in the Bering Sea and Sea of Okhotsk remained frozen though all of August, and all but 3 days in September.
Care to document that statement, it doesn’t agree with any of the satellite images I’ve seen.
The Bering sea had a historically low maximum this spring and has now melted out.
Nope, not true.
NSIDC regional data for 6 June 2018 still has Bering Sea Ice extent up at 14,000 sq km, Bering Sea ice area lower at 4,500 sq km^2.
https://nsidc.org/arcticseaicenews/sea-ice-tools/
Both down from their 1980-2010 averages, but neither has melted out. Both a little below where they were 2016 and 2017 on this date. Same as 2015 though.
Hudson Bay is much higher than 2016 or 2017 on this date, Sea of Okhotsk about the same as Bering Sea: Not quite as high an area as 2016-2017, but still higher than 2015. We shall see what happens through the summer.
Germinio May 24, 2018 at 6:36 pm
You see the part up there at the end of the head post where it says to QUOTE THE EXACT WORDS THAT YOU ARE DISCUSSING?
Come back when you are willing to do that. Until then, you can rot. I have no clue what you are babbling about, but your tone is ugly.
w.
Willis:
You state “My own strong wish in all of this is that climate scientists should declare a twenty-year hiatus in making long-range predictions of any kind, and just focus on trying to understand the past.”
My question is whether or not you will follow your own stated wish and stop making any predictions about the future climate yourself? A claim that the global temperature is stable and will not change due to raising CO2 levels is just as much a prediction as one that claims it will increase.
Germinio May 24, 2018 at 7:56 pm
Are you really a stupid person, or do you just play one on TV? I have no idea what “predictions about the future climate” you think I’ve made, but until you QUOTE THE EXACT WORDS OF MY SO-CALLED “PREDICTIONS” you can stew in your own bile …
w.
Willis,
It is quite simple. You frequently claim that there is a thermo-regulatory engine in operation that
controls the temperature. The direct implication of this is that you are claiming that the temperature
will be stable and that the effects of increasing CO2 are small to non-existent. This is a definite prediction about the future climate. You might not have stated it as such but it is trivial consequence of your theory.
@germinio
“You frequently claim that there is a thermo-regulatory engine in operation that controls the temperature. ”
Who doesn’t claim that?
“The direct implication of this is that you are claiming that the temperature will be stable”
Non sequitur. Your body has a “thermo-regulatory engine in operation that controls the temperature”, but variation nonetheless occur.
“and that the effects of increasing CO2 are small to non-existent.”
Non sequitur again. IPCC also claim that there is such engine, but it also claim that CO2 is sort of a control knob with great effect.
Germinio, so basically you are asking Willis to stop doing what you admit that he has never done?
Geronimo,
Please show where Willis made a specific prediction about the future.
tia
I think you should have quoted fully as requested. You misrepresent because you feel offended.
But don’t worry, we know your style.
germinio ,you are asking willis the equivalent of the “when did you stop beating your wife” question. not clever and i am glad to see it got the response it deserved.
Geronimo is simplybtrying to silence skeptics.
dnftt
Hunter,
I am not trying to silence skeptics but merely suggesting that they should follow their own advice. Personally
I think it is far more fun giving them rope and watching them hang themselves. I notice for instance no one here has commented on the theory proposed by Mo Brooks that sea level rise was caused by rocks falling into the ocean. As the saying goes with friends like those who needs enemies.
The 1930s were a famously āhotā decade, the warmest on record until the last 20 years or so.
So if rising atmospheric temperatures are causing an increase in the acceleration of sea level rise now, why was there a decrease in the acceleration in the 1930s which had similar atmospheric temperatures?
pauly
The 1730’s were the hottest on record until the 1990’s. They came to a shuddering halt in 1740 with one of the most severe winters in the record.
It caused Phil Jones to write a paper on the subject and remark that climate variation was greater than had hitherto been realised.
tonyb
As I mentioned, until we have some explanation of those changes, making predictions about the future sea levels is a most parlous endeavor ā¦
Making predictions is a most parlous endeavor. Yet the perils do not seem to deter anyone, least of all the climate speculators themselves.
There is a linear trend in modern times and it is fair to call for an explanation of that before panicking over any perceived changes from that trend.
Eyeballing the data and the two lines in Figure 2, for most years both lines are just as good. There are stretches where the data is below trend and stretches where it is above trend. For all of the past excursions, the data has returned to the trend line. For after 2000, the alarmist “prediction” is that this time it’s different, it’s not going to return to the long term trend line. Gavin is going to have to invent some better statistics to show that.
Schmidt and Mann both blocked me on twitter last July for demanding a scientific explanation of how a piece of the Larsen C ice shelf was doing anything to “hold back” the glacier if it was able to float away? I maintained and continue to maintain that it is physically impossible for any solid to do that if it is in compression. Of course they had to block me, it was their only alternative to admitting that they are completely wrong on that point. (Plus my tweets to them and their replies were all deleted from my view BTW..)
:large
I understand that a person may block someone else from its thread.
I also understand that NO public funded institution as any right to block anyone. Everybody is entitled to everything they produce, including any tweets. And they alos have no right to delete such public records.
So if PSUclimate is somehow related to Penn State uni, and blocks you, you can sue them, and they will lose.
And if PSU climate is not related, they are not entitled to the claimed affiliation, with just as nasty legal consequences for making the claim.
Another proof they don’t care about the public or the law.
Before you fit anything add the actual error bars. They aren’t less than 1 mm. Any analysis after that is hypothetical exercising
I fail to understand the urge to fit straight lines to every data set available. It is a well known adage that there are no straight lines in nature.
Willis. I notice the rate of sealevel rise has been around 1.5 – 1.6 mm/yr over the whole of the data set. The rate in the North Sea basin was about 1.9 mm/yr over the same period. These rates are way less than the 3 mm/yr measured with satellites. Yet the two tidal gauge data sets are taken thousands of miles apart. This suggests to me that neither is a local aberation but that the satellite stuff is ‘biased’.
Another point about fitting curves to this kind of data and error estimates. There are two crucial assumptions underlaying the least squares method. The first is that your model, the curve, properly represents the underlying process. The second, much less appreciated but equally crucial, in particular for error analysis, is that the residuals are random and follow a Gauss distribution. The latter is obviously not the case here, the residuals are correlated with the next one partly determined by its predecessor. This mucks up the estimates of significance big time, unfortunately. Perhaps a better method to analysis this kind of data is to use ARIMA models.
Willis, an important point I think you should remember to address is that a higher order fit ALWAYS has smaller residuals. It’s simply a fact. Saying that with no qualifier as Gavin did is ridiculous. Without an anaylsis of the type you show here (there are other ways to address this) Gavin’s statement is at best foolish.
Spot on!
+1
I say to Gavin, GISS should get out of climatology and look for aliens. Use your computer programming skill to detect alien signals instead of “adjusting” temperature data. BTW you can’t hear the aliens. She’s just listening to Red Hot Chili Peppers
http://www.btchflcks.com/wp-content/uploads/2016/07/Contact.jpg
She is listening RHCP ? not even one of the other of a number of “aliens” or “the aliens” band?
RHCP look like aliens. You think they’re Earthlings?
More important than linear or quadratic, world sea-level has been rising since 1850. What is causing that?
When we measure sea level change, is there any way to account for changes in the volume of the container? If I have a bucket of water, and add a hand full of sand, the water level goes up. If the earths rivers are constantly depositing silt into the oceans, how do I separate the causes for sea level change? Does sea level have any meaning at all when the shape of the container itself is constantly changing?
They have little meaning full stop , and by that I mean ‘scientific ā , the story around āscary headlines ā is a different game . And is this climate āscienceā that is the game that matters.
I think even Gavin could haul his over-stuffed behind away from a couple millimeters/yrs rise. Go, Gavin!
Interesting. From your graph, Church & White 2011, it looks like we are not out of the little ice age yet. How did Church & White come up with the “0” around 1975? Since about 1975 the oceans have risen about 2″ or about 1.28/32″ per year. Whoopee doooooo.
@ Willis:
Have you considered residual plots for the red and blue curves? I don’t have the data, but looking by eye, the blue trendline seems to have residuals that show more trend than the red. If we’re talking bets, that would give the odds edge to the red curve.
There is no money in that.
Willis Thanks for taking and clarifying the first steps in statistical analysis to see if the apparent sea level āaccelerationā is really significant.
Richard Feynman (1974) admonished:
For those wishing to take the next steps in scientifically how not to fool ourselves or the laymen, see the international (JCGM/WG 2008) and NIST (1994) guides to the expression of uncertainty in measurement, neither of which the IPCC appears to dare reference or follow. Note particularly Type B errors which can include systematic uncertainties and systemic errors. Those can be as large or larger than the statistical Type A errors Willis was exploring.
Feynman, R.P., 1974. Cargo cult science. Engineering and Science, 37(7), pp.10-13. http://calteches.library.caltech.edu/51/2/CargoCult.htm
JCGM/WG 1 2008 Working Group. Evaluation of measurement dataāguide to the expression of uncertainty in measurement. InTech Rep JCGM 100: 2008 (BIPM, IEC, IFCC, ILAC, ISO, IUPAC, IUPAP and OIML 2008.)
https://www.bipm.org/en/publications/guides/gum.html
Taylor BN, Kuyatt CE. Guidelines for evaluating and expressing the uncertainty of NIST measurement results. Gaithersburg, MD: US Department of Commerce, Technology Administration, National Institute of Standards and Technology; 1994 Sep 1.
https://dx.doi.org/10.6028/NIST.tn.1297
The increase in slr is trivial, slow and changing little if any.
No matter how the alarmists and climate profiteers declare otherwise.
Willis, you are far more patient and diplomatic than most.
Keep up the good work.
Fig 1. There just has to be a link with this graph and the USA 1930s dustbowl temperatures, which are anomalously high in unadjusted data (and in human experience).
Is the 31 year trailing average moving the peak effectively forward 20 years?
Ah, error measurement, the bane of climate scientists everywhere. Those pesky error bars are always getting in the way explaining why we never see them associated with, well, anything.
For a moment, I thought the title said: āGuest post by Willis Eschenbach and Gavin Schmidt….ā
Nearly had a heart attack….
R
Willis, I mentioned this article in a blog posting:
Hide the Decline Part Deux
https://co2islife.wordpress.co
The last two years of satellite data is pretty flat.
If by ‘pretty flat’ Bill you mean Sea Level satellite data, as of Dec 2017, is at the highest ever recorded, then yes, except obviously still rising.
“For ppl (like @mattwridley) who still want to ignore the facts of sea level rise” … that bit of arrogance says it all. No humility, no willingness to concede integrity on the part of other scientists who see things differently (or who suggest that they might be seen differently).
Any person given to doomsaying, name-calling, or indeed any kind of religious fervor in the practice of science is unfit to be called a scientist.
Willis, A- why do your first two Church & White charts contradict each other? The first shows a large decline from 1900 – 1940 while the second shows nothing of the sort. In fact the 2nd shows a steady rise during that same time frame.
B- In your 2nd C&W chart why is a rise of 200+mm w your linear trend blue line fit considered ‘No Acceleration’ by yourself?
There is no contradiction, Lou. The two charts are showing very different things It appears that you are confusing the acceleration (slope of the line in the first map) with the trend (slope of the line in the second map).
In mathematical terms the trend is the first derivative of the data and the acceleration is the second derivative.
Regards,
w.
Thanks for your reply Willis. So what you’re saying is that including the second derivative data(acceleration) with the first derivative data(trend) to give you an overall trend line is how you claim ‘No Acceleration’ in that particular graph? Isn’t that a mathematical impossibility? Including your second derivative which is acceleration into your first derivative trend line is adding acceleration to your trend. So the ‘No Acceleration’ blue line would be incorrect.
You seem to have confused my two questions. In the first I was questioning your choice of a 1.4mm chart v a 250mm chart as the first shows no trend line.
Gavin uses Fortran . You can’t think in Fortran .
http://cosy.com/Science/NotationExamples.gif
It takes just a handful of lines in an APL to quantitatively disprove the spectral GHG hypothesis for Venus , ergo , in general .
Are programmers/computer science types drifting away from STEM attitudes and disciplines and getting closer to other, less demanding fields? Some thoughts from Lubos here: ‘The three “main” sections ā mathematics, physics, and computer science ā were comparably geeky in their own ways. I was recently led to believe that the computer science folks, not particularly at that school but probably also at that school, have drifted most quickly towards the “ordinary people” that are increasingly incorporated into the cultural Marxist scheme of the world.’
https://motls.blogspot.co.uk/2018/05/most-programmers-think-like-folks-in.html
Willis wrote: “So what I did was to generate a thousand samples of pseudodata which had about the same Hurst Exponent (Ā± 0.05) as each residual, and which on average had the same variance as each residual.”
What was the Hurst exponent you used? Why did you add +/-0.05 to that exponent before creating the pseudodata?
I’ve experimented with satellite altimetry data before, using Excel to do a multiple linear regression with both t and t^2. (If you make t=0 the midpoint of the period, there is no correlation between t and t2.) Using this approach, if the 95% confidence interval for the t^2 coefficient includes zero, the acceleration is not statistically significant. I presume this is the standard approach, but this details are not disclosed.
The tricky part is that sea level data is highly auto-correlated, with a lag_1 correction of 0.96 (IF I remember correctly). The Quenouille correction reduced the number of independent data point from one per month to one every 18 months (for satellite altimetry data). You address this problem using a Hurst exponent, but I have no experience with using this approach. In the end, “statistical significance” depends on your assumptions about the nature of the noise present in your data and the rigor with which you analyze it.
Whether or not acceleration is “statistically significant” is far less important than the central estimate for acceleration. The acceleration detected in the satellite data is consistent with the IPCC’s central estimate for SLR (about 2X more SLR this century than last), and far below what is needed to reach 1 m or more.
Whether or not acceleration is āstatistically significantā is far less important than the central estimate for acceleration.
==================
unless of course the acceleration is actually an oscillation.
fredberpie: There is little chance we need to worry about any oscillations in the near future. With the 5 K of warming at the end of the last ice age sea level rose about 120 m or 24 m/K. It has warmed about 1 K over the last century. As ice caps have retreated poleward, the is less ice to melt per K of warming, so the future may not hold anything close to 24 m/K of SLR. Even 10% or 20% concerning.
The rapidly melting at the end of the last ice age ended about 7000 years ago and SLR slowed below the 20th-century rate around then. As temperatures dropped slightly since the Holocene Climate Optimum, SLR has basically come to a stop over the last 4 millennia – and presumably restarted at the end of the LIA. Until we enter another LIA (which rising GHGs as likely to overwhelm), you won’t need to worry about oscillating SL. The direction isn’t in question – the rate is.
Re: “My own strong wish in all of this is that climate scientists should declare a twenty-year hiatus in making long-range predictions of any kind, and just focus on trying to understand the past.”
My prediction — Climate “scientists” (alarmists) depend on long-range doomsday predictions to ensure their income. I predict this will either not change in twenty years or will exactly follow a hockey stick graph until we reach a tipping point of “fed up.”