Guest Post by Willis Eschenbach
Among the recent efforts to explain away the effects of the ongoing “pause” in temperature rise, there’s an interesting paper by Dr. Anny Cazenave et al entitled “The Rate of Sea Level Rise”, hereinafter Cazenave14. Unfortunately it is paywalled, but the Supplementary Information is quite complete and is available here. I will reproduce the parts of interest.
In Cazenave2014, they note that in parallel with the pause in global warming, the rate of global mean sea level (GMSL) rise has also been slowing. Although they get somewhat different numbers, this is apparent in the results of all five of the groups processing the satellite sea level data, as shown in the upper panel “a” of Figure 1 below

Figure 1. ORIGINAL CAPTION: GMSL rate over five-year-long moving windows. a, Temporal evolution of the GMSL rate computed over five-year-long moving windows shifted by one year (start date: 1994). b, Temporal evolution of the corrected GMSL rate (nominal case) computed over five-year-long moving windows shifted by one year (start date: 1994). GMSL data from each of the five processing groups are shown.
Well, we can’t have the rate of sea level rise slowing, doesn’t fit the desired message. So they decided to subtract out the inter-annual variations in the two components that make up the sea level—the mass component and the “steric” component. The bottom panel shows what they ended up with after they calculated the inter-annual variations, and subtracted that from each of the five sea level processing groups.
So before I go any further … let me pose you a puzzle I’ll answer later. What was it about Figure 1 that encouraged me to look further into their work?
Before I get to that, let me explain in a bit more detail what they did. See the Supplemental Information for further details. They started by taking the average sea level as shown by the five groups. Then they detrended that. Next they used a variety of observations and models to estimate the two components that make up the variations in sea level rise.
The mass component, as you might guess, is the net amount of water either added to or subtracted from the ocean by the vagaries of the hydrological cycle—ice melting and freezing, rainfall patterns shifting from ocean to land, and the like. The steric (density) component of sea level, on the other hand, is the change in sea level due to the changes in the density of the ocean as the temperature and salinity changes. The sum of the changes in these two components gives us the changes in the total sea level.
Next, they subtracted the sum of the mass and steric components from the average of the five groups’ results. This gave them the “correction” that they then applied to each of the five groups’ sea level estimates. They describe the process in the caption to their graphic below:

Figure 2. This is Figure S3 from the Supplemental Information. ORIGINAL CAPTION: Figure S3: Black curve: mean detrended GMSL time series (average of the five satellite altimetry data sets) from January 1994 to December 2011, and associated uncertainty (in grey; based on the dispersion of each time series around the mean). Light blue curve: interannual mass component based on the ISBA/TRIP hydrological model for land water storage plus atmospheric water vapour component over January 1994 to December 2002 and GRACE CSR RL05 ocean mass for January 2003 to December 2011 (hybrid case 1). The red curve is the sum of the interannual mass plus thermosteric components. This is the signal removed to the original GMSL time series. Vertical bars represent the uncertainty of the monthly mass estimate (of 1.5 mm22, 30, S1, S3; light blue bar) and of the monthly total contribution (mass plus thermosteric component) (of 2.2 mm, ref. 22, 30, 28, 29, S1, S3; red bar). Units : mm.
So what are they actually calculating when they subtract the red line from the black line? This is where things started to go wrong. The blue line is said to be the detrended mass fluctuation including inter-annual storage on land as well as in water vapor. The black line is said to be the detrended average of the GMSL The red line is the blue line plus the “steric” change from thermal expansion. Here are the difficulties I see, in increasing order of importance. However, any of the following difficulties are sufficient in and of themselves to falsify their results.
• UNCERTAINTY
I digitized the above graphic so I could see what their correction actually looks like. Figure 3 shows that result in blue, including the 95% confidence interval on the correction.
Figure 3. The correction applied in Cazenave14 to the GMSL data from the five processing groups (blue)
The “correction” that they are applying to each of the five datasets is only statistically different from zero for 10% of the datapoints. This means that 90% of their “correction” is not distinguishable from random noise.
• TREND
In theory they are looking at just inter-annual variations. To get these, they describe the processing. The black curve in Figure 2 is described as the “mean detrended GMSL time series” (emphasis mine). They describe the blue curve in Figure 2 by saying (emphasis mine):
As we focus on the interannual variability, the mass time series were detrended.
And the red curve in Figure 2 is the mass and steric component combined. I can’t find anywhere that they have said that they detrended the steric component.
The problem is that in Figure 2, none of the three curves (black:GMSL, blue:mass, red:mass + steric) are detrended, although all of them are close. The black curve trends up and the other two trend down.
The black GMSL curve still has a slight trend, about +0.02 mm/yr. The blue steric curve goes the other way, about -0.6 mm/yr. The red curve exaggerates that a bit, to take the total trend of the two to -0.07 mm yr. And that means that the “correction”, the difference between the red curve showing the mass + steric components and the black GMSL curve, that correction does indeed have a trend as well, which is the sum of the two, or about a tenth of a mm per year.
Like I said, I can’t figure out what’s going on in this one. They talk about using the detrended values for determining the inter-annual differences to remove from the data … but if they did that, then the correction couldn’t have a trend. And according to their graphs, nothing is fully detrended, and the correction most definitely has a trend.
• LOGIC
The paper includes the following description regarding the source of the information on the mass balance:
To estimate the mass component due to global land water storage change, we use the Interaction Soil Biosphere Atmosphere (ISBA)/Total Runoff Integrating Pathways (TRIP) global hydrological model developed at MétéoFrance22. The ISBA land surface scheme calculates time variations of surface energy and water budgets in three soil layers. The soil water content varies with surface infiltration, soil evaporation, plant transpiration and deep drainage. ISBA is coupled with the TRIP module that converts daily runo simulated by ISBA into river discharge on a global river channel network of 1 resolution. In its most recent version, ISBA/TRIP uses, as meteorological forcing, data at 0.5 resolution from the ERA Interim reanalysis of the European Centre for Medium-Range Weather Forecast (www.ecmwf.int/products/data/d/finder/parameter). Land water storage outputs from ISBA/TRIP are given at monthly intervals from January 1950 to December 2011 on a 1 grid (see ref. 22 for details). The atmospheric water vapour contribution has been estimated from the ERA Interim reanalysis.
OK, fair enough, so they are using the historical reanalysis results to model how much water was being stored each month on the land and even in the air as well.
Now, suppose that their model of the mass balance were perfect. Suppose further that the sea level data were perfect, and that their model of the steric component were perfect. In that case … wouldn’t the “correction” be zero? I mean, the “correction” is nothing but the difference between the modeled sea level and the measured sea level. If the models were perfect the correction would be zero at all times.
Which brings up two difficulties:
1. We have no assurance that the difference between the models and the observations is due to anything but model error, and
2. If the models are accurate, just where is the water coming from and going to? The “correction” that gets us from the modeled to the observed values has to represent a huge amount of water coming and going … but from and to where? Presumably the El Nino effects are included in their model, so what water is moving around?
The authors explain it as follows:
Recent studies have shown that the short-term fluctuations in the altimetry-based GMSL are mainly due to variations in global land water storage (mostly in the tropics), with a tendency for land water deficit (and temporary increase of the GMSL) during El Niño events and the opposite during La Niña. This directly results from rainfall excess over tropical oceans (mostly the Pacific Ocean) and rainfall deficit over land (mostly the tropics) during an El Niño event. The opposite situation prevails during La Niña. The succession of La Niña episodes during recent years has led to temporary negative anomalies of several millimetres in the GMSL, possibly causing the apparent reduction of the GMSL rate of the past decade. This reduction has motivated the present study.
But … but if that’s the case then why isn’t this variation in rainfall being picked up by the whiz-bang “Interaction Soil Biosphere Atmosphere (ISBA)/Total Runoff Integrating Pathways (TRIP) global hydrological model”? I mean, the model is driven by actual rainfall observations, including all the data of the actual El Nino events.
And assuming that such a large and widespread effect isn’t being picked up by the model, in that case why would we assume that the model is valid?
The only way that we can make their logic work is IF the hydrologic model is perfectly accurate except it somehow manages to totally ignore the atmospheric changes resulting from El Nino … but the model is fed with observational data, so how would it know what to ignore?
• OVERALL EFFECT
At the end of the day, what have they done? Well, they’ve measured the difference between the models and the average of the observations from the five processing groups.
Then they have applied that difference between the two to the individual results from the five processing groups.
In other words, they subtracted the data from the models … and then they added that amount to the data. Lets do the math …
Data + “Correction” = Data + (Models – Data) = Models
How is that different from simply declaring that the models are correct, the data is wrong, and moving on?
CONCLUSIONS
1. Even if the models are accurate and the corrections are real, the size doesn’t rise above the noise.
2. Despite a claim that they used detrended data for their calculations for their corrections, their graphic display of that data shows that all three datasets (GMSL, mass component, and mass + steric components) contain trends.
3. We have no assurance that “correction”, which is nothing more than the difference between observations and models, is anything more than model error.
4. The net effect of their procedure is to transform observational results into modeled results. Remember that when you apply their “correction” to the average mean sea level, you get the red line showing the modeled results. So applying that same correction to the five individual datasets that make up the average mean sea level is … well … the word that comes to mind is meaningless. They’ve used a very roundabout way to get there, but at the end they are merely asserting is that the models are right and the data is wrong …
Regards to all,
w.
PS—As is customary, let me ask anyone who disagrees with me or someone else to quote the exact words that you disagree with in your reply. That way, we can all be clear about what you object to.
PPS—I asked up top what was the oddity about the graphs in Figure 1 that made me look deeper? Well, in their paper they say that the same correction was applied to the data of each of the processing groups. Unless I’m mistaken (always possible), this should result in a linear transformation of each month’s worth of data. In other words, the adjustment for each month for all datasets was the same, whether it was +0.1 or -1.2 or whatever. It was added equally to that particular month in the datasets from all five groups.
Now, there’s an oddity about that kind of transformation, of adding or subtracting some amount from each month. It can’t uncross lines on the graph if they start out crossed, and vice versa. If they start out uncrossed, their kind of “correction” can’t cross them.
With that in mind, here’s Figure 1 again:
Figure 1 redux …
I still haven’t figured out how they did that one, so any assistance would be gratefully accepted.
DATA AND CODE: Done in Excel, it’s here.
What happens to the amount of water vapor in nino and nina states, given this extract:-
“So, are the satellite estimates reliable? Well, in order to answer that, we have to learn a little bit about how they were actually constructed.
Unfortunately, satellite altimeters don’t actually measure sea levels directly. Instead, they measure the length of time it takes light signals sent from the satellite to bounce back. In general, the longer the signal takes, the further the satellite is from the sea surface. So, in theory, this measurement could be converted into a measure of the sea surface height, i.e., the mean sea level.
However, the conversion is complicated, and a number of other factors need to be estimated and then taken into account. For instance, the distance of the satellite from the Earth’s surface varies slightly as it travels along its orbit, because the gravitational pull of the Earth is not exactly uniform – see the Wikipedia page on “geoid”, and the maps in Figure 19.
So, in order to convert a particular “satellite-sea surface distance” into a sea level measurement, the “satellite-Earth’s surface distance” also needs to be independently measured, e.g., using the DORIS system.
Another complexity is that light takes slightly longer to travel when travelling through water vapour than dry air. So, the water vapour concentrations associated with a given satellite reading also need to be estimated, and accounted for.”
http://notalotofpeopleknowthat.wordpress.com/2014/03/21/ronan-connolly-on-sea-levels/
I had a letter that I can’t find but wish I could. I sent it to Richard Torbay years ago, asking that I felt Tim Flannery’s prediction (Like Al Gore’s) of impending sea level rises was flawed. I got a letter back from the BOM, that predicted 177 MM rise by 2050. Not cms, well I am sure we can deal with what 6.5 inches without selling one’s expensive water fronts.
The Remains of The Day, This Day.
LOL !!!!
(y)
1. Check
2. Check
3. Check
4. Check
Once upon a time ago I had respect for Anny Cazenave.
Not now.
Nothing at all. Nothing remains.
The Remains of the Day, This Day.
The problem is with me, I don’t have the patience nor knowledge to look at graphs, I had enough of them in school. So depend on someone to interpret them. We wouldn’t have fresh water unless rain fell on land, and why, because the sea evaporates and with galactic sub atomic particles help create clouds. Sounds simplistic, well I think it is.
If Trenberth were right about all that missing heat ending up deep in the oceans, wouldn’t it cause some noticeable rise in sea levels?
Willis,
If it were a linear function, besides maintaining the crossing nature the difference between wouldn’t change either. The second graph is definitely more compressed. Perhaps they mislabeled the Y axis, or some other FUBARism.
v/r,
David Riser
You can read the paper here.
More on this paper, which claims that the missing heat is still increasing in the oceans causing thermal expansion, but that sea level rise has decelerated because a model conveniently says ENSO made it rain more over land [and less over the oceans]!
http://hockeyschtick.blogspot.com/2014/03/new-paper-finds-global-sea-level-rise.html
The authors also find that even with this huge adjustment to sea level rise, there is no evidence of acceleration over the past 20 years, which means there is no evidence of a human influence on sea levels.
The authors redeem themselves a bit in the conclusion and appear to contradict their earlier statements in the paper: “Although progress has been achieved and inconsistencies reduced, the puzzle of the missing energy remains, raising the question of where the extra heat absorbed by the Earth is going. The results presented here will further encourage this debate as they underline the enigma between the observed plateau in Earth’s mean surface temperature and continued rise in the Global Mean Sea Level [GMSL].”
Climate science has sunk just like the ‘missing heat’ to the depths of the ocean trying to explain away the “pause” of both global warming and global sea level rise, using synthetic data generated by climate models that can be programmed to obtain any result one desires.
She’s a data tweaker, but still shows sea level rise slowed, not that I worry, here @ 1300′.
I presume they detrended each of the lines separately. So each has a slightly different value applied, because each has a slightly different gradient in the original.
The FIRST sentence after the abstract:
“Precisely estimating present-day sea-level rise caused by anthropogenic global warming is a major issue that allows assessment of the process-based models developed for projecting future sea level.”
I beg your pardon? A major issue “allows assessment”? How does one “precisely estimate” something? What the hell are you people smoking? Let’s just look at this for a second. A precise estimate can be used to ‘project’ future sea level? Er, isn’t this just a goddamn GUESS? Thanks, Nick Stokes, for providing us a link to the paper…paywalled?? What nature of CRAP is paywalled these days!! I think the reviewers are borderline illiterate if they can allow such a cumbersome statement of import in the INTRODUCTORY SENTENCE……..
“Sea-level rise is indeed one of the most threatening consequences of ongoing global warming, in particular for low- lying coastal areas that are expected to become more vulnerable to flooding and land loss.”
…I guess…
yep, Willis, you are braver than most to even TRY to ‘analyze’ the ‘data’ that allowed these otherwise talentless zombies to
precisely estimateguess the reasons for an imperceptible change in sea level rate. What gets in my craw is their singular cause…that global warming is the ONLY cause of plus-delta sea level….then they smear it with meaningless drivel accompanied by ‘sciency-looking’ graphs and stats. Amazing, truly amazing.Why does their graph stop just before 2010? Seems they have data all the way out to about 2012. Is it because the La Nina would put a big downward spike at the end of their graph (even in the corrected “b” version) and make it look bad?
Our measurements of a surface in motion are getting more precise.
But are we just measuring Jell-O after its been disturbed, and within our limited timeframe ?
Still, at the end of the day, tide gauges are the only ones that matter. They are the ones most accurate and tell you most accurately exactly where you have to (or not) worry about sea level encroachment (regardless of the cause). And if you have thousands of them around the world you will also get the most accurate measure of average sea level rise (or fall). If a satellite tells me my house should be under water, but I am standing in the back yard and my tide gauge says all is fine, which one should I believe?
Willis, one of your best nonsense paper deconstructions yet. Absolutely spot on. Your summary logic is irrefutable. Many thanks for a good read and a great laugh.
About the de-trending etc : the way I read it, they de-trended the data to get the inter-annual variation, which they then subtracted from the data (not from the de-trended data). Under figure 2 it says “This is the signal removed to the original GMSL time series” [presumably they meant ‘from’ not ‘to’]. The end -result of that would presumably be just the trend, and part b of the graph is pretty close to horizontal – ie. just the trend.
I don`t get it. If the objective is to somehow quantify trends in sea levels, why start de-trending the data then add, subtract, sum, and subtract again. Maybe I missed a step or two. But when looking for trends, why de-trend before you look for trends? My head is starting to hurt. How do things like this get published?
Willis,
Well, we can’t have the rate of sea level rise slowing, doesn’t fit the desired message. So they decided to subtract out the inter-annual variations in the two components that make up the sea level—the mass component and the “steric” component. The bottom panel shows what they ended up with after they calculated the inter-annual variations, and subtracted that from each of the five sea level processing groups.
The above is formatted as if it’s part of the caption for Fig.1. Was it really part of the original caption? It reads like your perspective, though.
[Thanks, Katherine, well spotted. I wondered where that paragraph had gotten to … it got swept up in the caption. -w.]
Applying Occam’s Razor and the great ocean flow patterns, all the how water is at the top and all the cold is at the bottom. The can be no deep hot current. Period. That,s my conclusion and I am sticking with it.
Looks like some very dodgy pseudoscience. How to tell? Remove the trend the simple way.
Take the original CU data, calculate rate of change by taking differences. get an average of all difference data = -0.114
Now subtract -0.114 from each difference, which moves the difference line up by exactly 0.114,
then reverse the now adjusted (0.114) difference data via a cumulative sum and bingo, the trend is no longer.
Whether intentionally or unintentionally, this is what they have done. They have made the detrended data just a widdle bit positive. Doesn’t have to be much (only 0.114!!)
From Willis’ excel, the diff between before and after (ave. for each set):
0.20 0.24 0.32 0.19 0.24
Computerised modelling takes up many person years of climate scientists time and energy it is therefore not surprising that they write justifications for their investment and their product. Naturally their justification will support their choice of addiction.
Has anyone estimated the amount of water delivered to our planet from space? That could be a used as a convenient fudge-factor
The money quote from Willis is: “The only way that we can make their logic work is IF the hydrologic model is perfectly accurate except it somehow manages to totally ignore the atmospheric changes resulting from El Nino … but the model is fed with observational data, so how would it know what to ignore?”
Incorporating the comment from DocMartyn above, what we have here is not a set of observations and a set of model outputs, we have two sets of model outputs one of which is assumed to be perfect.
Fundamentally, the authors trust the model of water sloshing around the hydrosphere more than they trust the model of sea levels produced by the satellite pings-times-fudge-factors-and-corrections-applied as people now think they should be, i.e. with current understandings and within the limits of their equipment.
This tends to weaken the level of nefariousness one might say is there, but is really just telling us which model they trust most.
Personally I would trust the model with the least number of steps, assumptions and fiddles. Thus I will trust the satellite results more than the rainfall (etc) and steric modeling version of the same thing (which is also based on observations that have corrections and assumptions).
As for uncrossing lines, well spotted. Is it perhaps an artifact of the smoothing method? Is there a different method used in the two sets that produce the graphs? That at least is a simple explanation and could produce the same effect.
Thermal changes to sea water results in a rise, or fall, in the sea level. But there are other inputs many of which are not measured.
Sedimentary rates, total erosion rates, plate tectonic effects on the sea floor, continental crust growth, all affect sea levels and mainly to increase them.
Anny says in her abstract “However, over the last decade a slowdown of this rate, of about 30%, has been recorded. It coincides with a plateau in Earth’s mean surface temperature evolution, known as the recent pause in warming”
Occam’s razor has something to say about this and it doesn’t include modelled output comparisons.
Anny also writes in the paper “This decreasing GMSL rate coincides with the pause observed over the last decade in the rate of Earth’s global mean surface temperature increase, an observation exploited by climate sceptics to refute global warming and its attribution to a steadily rising rate of greenhouse gases in the atmosphere”
Oh and “exploited” by climate sceptics ? Nice one Anny. Thanks for painting a big “biased” target on your paper. It makes it much easier for true sceptics to find papers that are likely to be trash.
This is yet another major embarrassment of the models and claims concerning SLR. The ocean is basically a giant thermometer. It is asserted that missing heat is disappearing into the deep ocean (raising its temperature by an amount far smaller than the reliable resolution of their measuring devices that is nevertheless reported as if it is a meaningful number). At the same time, satellites are doing to SLR what they have done to claims about the surface temperature record — they are starting to impose a strict upper bound to sanity, because not even the most egregious recomputation of net satellite SLR can make a negative rate into a positive rate, and it appears that SLR has gone negative with the last La Nina. This paper is attempting to claim not that SLR is continuing to increase (the data confounds that), but that they can somehow infer a continuing increase in the total liquid plus vapor water (as opposed to ice) in the global water system, so that they can assert that glaciers and polar icecaps are continuing to melt. However, SLR in the past has never been presented with the opposite correction, the correction one might reasonably expect from water running off land and leaving the atmosphere or adding to glacial ice. For good reason — we have no meaningful data on any of the above — we have at best sparse samples on a huge planet. GRACE might soon give us a better picture of the big ice repositories and for that matter the ocean, but so far the news from GRACE is bad news for SLR as it shows that if anything SLR is being slightly inflated by the satellites compare to the actual mass that is supposedly raising the sea level.
Negative SLR is a disaster for all claims for warming, because the ocean is a giant thermometer. One is stuck between a rock and a hard place. If one asserts that the water is ending up in the air, it should show up in increased clouds and albedo and cooling. If one asserts that the water is ending up on land (but not as ice) then one’s claims of drought and famine “evaporate” — quite the opposite — and one expects to see the water show up in the air, in increased cloudiness, in cooler land surface temperatures as it evaporates and increases latent heat losses. If one asserts that the water is getting bound up into ice, well, that’s the worst possible news for catastrophists, as it implies that the entire global subtext of shrinking glaciers and icecaps is false, or at least down there in the noise in the data. And even then one is constrained by sea surface data and ARGO data.
The GCMs are dying a death of a thousand cuts. Global surface temperatures aren’t increasing the way that they predict. Direct satellite measurements (and multiple soundings) of the troposphere limit any attempt to further monkey with the already corrupted station data they’ve adjusted in the past to create warming when the data refused to cooperate with the models. SSTs have for decades formed another major surface constraint on the models, and ARGO promises to do the same to depth. Now SLR is behaving precisely the way it did after the early 20th century warming that almost precisely matched the late 20th century warming — it is flattening out and returning to the plodding ~2 mm/year rate after a comparatively brief sojourn at a higher rate during the single 15 year stretch of late 20th century warming visible on in the average surface record. Even the IPCC is acknowledging that there are no species that have been driven to extinction by purported warming. Even the IPCC is forced to acknowledge that global weather has not displayed increased frequency or severity of storms (although the media and politicians seeking to sell catastrophe haven’t gotten the message). Even the IPCC has to acknowledge that the world is not suffering from an unusual number of droughts or floods, that in fact the world is pretty boring in this regard (especially compared to the 1930’s, for example, or the early 1600’s). Even the IPCC is forced to acknowledge “The Hiatus” (as they call it) and to try to explain the increasing divergence between model predictions and temperature, because they can read a graph and can see as well as anyone that if things continue as they are trending, no possible amount of curve-jiggering is going to fix AR6 to hide the fact that the GCMs in CMIP5 are toast, and with them, all of their egregious predictions of catastrophe.
The current AR5-fest is quite possibly the last hurrah of this particular golden horde. The data are at the outer range of their ability to claim that “warming continues”, and all they need is a FEW ways to jigger things like SLR that are failing to conform to their certainty that the models are more accurate than measured reality for just a bit longer and MAYBE, if they go for broke in this last brief interval before pesky nature quite possibly reveals that the “science” they’ve been presenting is far, far from certain, they can convince world leaders to beggar themselves and murder millions of people a year for decades in the name of catastrophic anthropogenic global warming by outlawing inexpensive energy throughout all human civilization.
rgb
alcheson said at 8:57 pm
Still, at the end of the day, tide gauges are the only ones that matter.
Besides that, the satellite data is managed by a small number of scientists who depend on government grants for a living.
As presdent Eisenhower said in 1961:
“The prospect of domination of the nation’s scholars by Federal employment, project allocations, and the power of money is ever present – and is gravely to be regarded.
Yet, in holding scientific research and discovery in respect, as we should, we must also be alert to the equal and opposite danger that public policy could itself become the captive of a scientific-technological elite.”
Thanks Willis. I notice the pause has SLR at 8″ a century, down from the ‘catastrophic’ 12″ per century.
Still, at the end of the day, tide gauges are the only ones that matter. They are the ones most accurate and tell you most accurately exactly where you have to (or not) worry about sea level encroachment (regardless of the cause). And if you have thousands of them around the world you will also get the most accurate measure of average sea level rise (or fall). If a satellite tells me my house should be under water, but I am standing in the back yard and my tide gauge says all is fine, which one should I believe?
It’s a bit more complicated than that — warm water is more buoyant than cold water because it expands, meaning that the ocean isn’t perfectly isostatic or isobaric. Further, the Earth isn’t spherical, is rotating, isn’t uniform in its mass distribution, and that mass distribution is moving at a significant rate as the tectonic plates move around and crust erupts and subducts. Non-uniform mass equals non-uniform distribution of oceanic water — it actually experience a significant lateral attraction to oceanic boundaries which causes water to pile up at continental shores relative to mid-ocean, or concentrates water in places like the Gulf or Mediterranean that are surrounded by land at a comparatively short distance relative to the surface curvature. Tide gauge data reflects a mix of all of this — the gauge itself can upheave or subside along with the coast it is sitting on, local warming or cooling of the ocean it measures (many tide gauges sit on rivers mouths and are subject to warming when the outflowing river warms) — response to warming or cooling mid ocean or to continental or land shifts, or simply response to slow changes in the patterns of tides all can contribute to variation that may or may not be significant. SOME tidal gauges are likely to show significant changes that aren’t GLOBALLY significant at all, and one has to hope that the “noise” factors are unbiased so that an average does reflect an oceanic mean.
The satellites — especially with the inclusion of GRACE to correct for gravitation — are likely to eventually do a much better job, but it is as you say good to have the coastal tide gauge data as a boundary condition and sanity check. It is entirely possible for the two to differ year to year, but it is not reasonable for the two to systematically diverge, just as it is not reasonable for RSS and UAH LTT to systematically diverge from the global average surface temperature.
We are actually getting to where it is no longer possible for ANY single source of global data to be jiggered by much because there are simply too many checks and balances. It is especially interesting that this time coincides with the pause, the hiatus, the plateau in global surface temperatures. GISS and HADCRUT are pretty much stuck, forcing the invention of entirely new ways of re-averaging surface data in order to maintain a warming rate since both have levelled off, but the new surface averages are being born into a world bounded by RSS and SSTs, and if they go up when the latter do not change (or go up egregiously over intervals in the past where the latter did not change) the game is over.
I suspect that we’re entering a period where the game, if any gaming has indeed been occurring, is over. Short of direct corruption, actually falsifying data, I don’t see any future in trying to continue to adjust processing methodology to produce the “missing heat”. The GCMs are sooner or later going to have to come face to face with the data itself in such a way that no amount of jiggering will save them, and I think a lot of climate scientists are seeing this and it is having a sobering effect on the entire discipline.
rgb
“The mass component, as you might guess, is the net amount of water either added to or subtracted from the ocean by the vagaries of the hydrological cycle”
johnmarshall beat me to it: the container is not a fixed size. They make the absolutely ridiculous assumption that “the ocean” has one size, and all surface level variability is from the addition or subtraction of water, mid ocean ridge be damned.
“detrended”…might as well call it a “cat in the hat” filter. We stuff it in here and comes out there.
Surely, the test is how far up the beach or cliff does the tide come at Spring High Tide and is it different to what it was fifty to a hundred years ago? Yes, I know wind strength and direction will make a difference. From the Met Office and the Ordance Survey the Mean Sea Level is just 7.5 inches rise since 1915 and that is how maps of the Uk are calibrated.
She lost me at hubris before we could get really hot and sweaty with complexity and chaos.
Another time perhaps?
Robert Brown, I assume you are also rgbatduke. I appreciate the depth of your feelings on this but one should not call it murder, but perhaps negligent homicide as the people advocating policies that end up causing deaths in the 3rd world are just too lazy or stupid to look at other arguments and realize they may be responsible for other’s deaths.
Subjective circular reasoning has been and is the biggest flaw in the CAGW argument and is not objective science. This morning I read the news article that the administration is using the CAGW argument to “justify” controlling anthropogenic emissions of methane. That is not science.
Losing the argument from green morons because they say so: http://www.breitbart.com/Big-Journalism/2014/03/28/Now-Nate-Silver-Capitulates-Needlessly-To-The-Green-Activists-And-Throws-His-Staffers-To-The-Wolves
Now wait just a gol dern minute. With CO2 rise, we can’t say that it is all just recycled stuff, even from burning oil. NOOOOO! It’s all “new” stuff added (so they say in essence we create CO2 out of nothing). We can’t just subtract it and say now look.
But this paper says that rain is different and they can subtract it from their data???? Well, turn about is fair play. If we can’t subtract CO2 rise from the data, they can’t subtract rain.
Yeh, I know I am being too simplistic, but there are times I just want to think about the bottom line and the 1 foot space in front of me. These are the times I wish we had a simple-minded pres in office who quaffs a cheap beer fairly regularly and names stupid when he sees it.
Why would they remove these effects if they were adding to total sea-level rise? Isn’t it important to know what the total sea-level rise is? After all, it’s not just the steric component that floods the town.
Robert Brown, I assume you are also rgbatduke. I appreciate the depth of your feelings on this but one should not call it murder, but perhaps negligent homicide as the people advocating policies that end up causing deaths in the 3rd world are just too lazy or stupid to look at other arguments and realize they may be responsible for other’s deaths.
Yeah, you are right. But then again:
http://www.who.int/mediacentre/factsheets/fs266/en/
…no less than the World Health Organization is perfectly happy to attribute “140,000 excess deaths since 1970 by 2004” to global warming.
Quite aside from the fact that this is total bullshit, who is tallying the deaths that are occurring because of the money we’re spending on measures that even the proponents of the measures agree will make no substantive difference in future global warming even if the most pessimistic predictions are right? Perhaps especially so.
What about all the fresh water that people have pumped up out of the ground or impounded upon it? If researchers really want to measure the human contribution to sea level rise, how about something more meaningful than CO2?
A long time a go in high school physics we became acquainted with the concept of the “universal-constant variable fudge factor” (U). When you boil it down, it’s just the ratio of expected results (X) to observed results(O), or U = X/O. When you know something is true, you don’t have to put up with pesky experimental noise. You can never be disappointed, at least initially, when your final result (F) is simply F = O*U. That was a very good lesson. Knowledge of the process has served us well, helping us keep an eye out for people using other similar methodologies.
I had a hard time with Willis’ post because it was never clearly stated the authors were trying to remove the el niño / la niña variations. Whether that is a good idea or not is a separate question. It seems they were successful in removing the “inter-annual” variations. Whether they have accurately described the steric and hydrological components in sea level rise is dubious. By adjusting parameters, no doubt any desired result could be obtained. Why should we be surprised they got their desired outcome?
As pointed out, the authors missed the last la niña. Do they need to adjust their method to make that last variation match their expectations? Keep watching Nature Climate Change for more!. Oh, how I feel the need to spend $199 for full access to that barrel of BS. Indeed, Nature calls. Gotta go.
There may be something here.
http://en.wikipedia.org/wiki/Mathematical_fallacy
Thanks, Willis. Another excellent deconstruction of a poor paper.
But it is not only that Cazenave2014 is poorly thought out; it was meant to mislead, in my opinion this is even worst.
When I hear about “papers”, like this one, Willis reports on, I don’t have time to check all the math and logic, so I often, just read them as anecdotes; unless somehow they move my curiosity.
Back when I was an undergrad, I did a lab experiment, using a 1cm Fabry Perot etalon, to measure the wavelengths of some lines in the Neon spectrum. The experiment procedure, described in the lab manual, used some ingenious tricks, to get around the limits of mechanical measurements of the quartz spacer in the etalon. But the procedure was easy to follow, and the lab took a couple of hours to measure half a dozen lines.
But I got into this marvelous instrument in a big way, and ended up spending a good part of a month of my time, which resulted in rewriting the lab manual, on that experiment.
I discovered, that you could not get very accurate results; dependent on measuring the actual optical length in air of this device. I ended up having to account for the changes in the refractive index of the air, because of the air temperature, the barometric pressure, the humidity, and I also corrected for the dispersion of the refractive index of moist air, over the total range of wavelengths that were measured.
I ended up measuring about 23 lines in the Neon spectrum, to a couple of parts in 10^8. This was way beyond what they had thought that etalon was capable of.
So when I hear that someone is measuring time of flight of photons, in the entire earth atmosphere thickness, I start to see wheels spinning in my head.
So what did they use for continuous monitoring of the refractive index profile of all that atmosphere thickness, when I found it was significant over just one cm of relatively stationary air..
Thanks Willis. I notice the pause has SLR at 8″ a century, down from the ‘catastrophic’ 12″ per century.
Which is, incidentally, almost exactly the 140 year average rate:
http://en.wikipedia.org/wiki/File:Trends_in_global_average_absolute_sea_level,_1870-2008_%28US_EPA%29.png
even including the brief “catastrophic” interval from 1930 to 1950 and the even briefer one from 1990 to 2009 (which conveniently enough is smoothed to avoid the hiatus, starting both rises a full decade after the actual warming). If that one is too noisy, you can always try this, generated from 23 “stable” tide gauge records:
http://commons.wikimedia.org/wiki/File:Recent_Sea_Level_Rise.png
Wow, an almost perfectly linear trend from 1900 to the present, without so much as a hint of a hockey stick to be found.
Of course it is always useful to put the last century in perspective:
http://en.wikipedia.org/wiki/File:Post-Glacial_Sea_Level.png
where both MWP and LIA are clearly evident as blips on an otherwise remarkably smooth curve. Oh, you can’t see much on this scale of tens to hundreds of meters? Try this:
http://commons.wikimedia.org/wiki/File:Holocene_Sea_Level.png
Not horribly consistent, but at least it shows the supposed noise. Curious how there is a clear uncertainty of over a meter in even remarkably recent data from various location specific proxies. Santa Catarina, Senegal, Rio — all bouncing up and down by meters according to data with uncertainties given as a few tens of centimeters over a timescale of a few hundred years when there is no friggin’ way that global sea level varied by more than a few tens of centimeters.
BTW, for all its warts, since sea level is arguably one of the best real smoothed thermometers out there, and note that the holocene at higher resolution shows sea level as being damn close to flat over the last 1000 years, flat within a few tens of centimeters. Even the LIA/MWP/RWP blips probably aren’t real — there is so much unbelievable spread in the data that the error bars presented are clearly meaningless, underestimating the actual error by meters. One can do better by using direct historical/geological/archeological data associated with actual harbors and ports over the post-Columbus era, although I don’t have any idea whether or where such a study might be found. But surely the British have ship quays that are centuries old in England, in India, and elsewhere around their empire with very clear records of mean sea level (and with equally clear opportunity to read off the past by means of carbon dating of barnacle layers and son on).
The thermometer of the ocean reveals basically no catastrophic alteration of the rate of global warming associated with anthropogenic CO_2 production in a way that is probably more accurate than any number of bristlecone pines. Sure, sea level is multivariate and not a simple linear proxy of temperature, but it is a slowly varying, mostly linear proxy of temperature and it would require an awe-inspiring coincidence for its multivariate dependence to have almost precisely cancelled its temperature-linked expansion to maintain a nearly perfectly linear, incredibly slow rate of increase across one or more centuries. The lack of any sort of resolvable fluctuation-correlation with either the late 20th century warming or the advent of rising CO_2 in general, the lack of any sort of structural relationship between the rise in CO_2 and rise in sea level (beyond the fact that both are monotonic) is a further problem.
As with all climatic records, I’ve always contended that if we are headed to a catastrophic future on all these elements, then the raw data will serve well to show this – probably 50 stations globally would do the job. The effort put into squeezing meaningless precision from data records is in itself the work of people who must in their subconscious be concerned we may not be heading for disaster and it may need a helping hand. If the sea is expected to rise a few or many metres in a century, why quibble over a millimetre or two in the present? If we are heading for 4-5C increase in a century, or even 2C, why must we be adjusting by a tenth or two the present record. The progress would be inexorable and obvious from the raw data. We definitely need competition in the record keeping business.
One nice of the things about computer models is you can easily adjust things to give the needed outcome. In the old days you had to hand graph the data and were stuck with the results as to rejigger the data was too much work and you would have to start all over again for each change. Computer programs today make things so easy and you can just point to “The Computer did it” so it must be correct!. pg
“and even in the air as well”
In which case it would presumably show up in the atmospheric water vapour content, which Humlum and Vonder Vaar’s analyses show to be effectively trendless post ~1980, and Solomon et al shows a 10% decrease in the decade post 2000.
Nick Stokes says:
March 28, 2014 at 8:04 pm
Thanks, Nick.
w.
ATheoK says:
March 28, 2014 at 8:54 pm
I’m ashamed to see that ‘sky ending on Lewny’s name; people of Polish and Ukrainian ancestry everywhere are similarly embarrassed.
===========================
They should be, it’s for the first case worldwide. We have our own Lew here in Brazil: Ricardo Lewandowsky, a Supreme Court Justice as pathetic as his namesake.
Alcheson says:
March 28, 2014 at 8:49 pm
Thanks, Alcheson. It stops in 2010 because it’s a five year centered average, so it stops two years before the end of the record.
w.
I think it’s important to figure out the right way to analyze sea level data in conjunction with other data and models, so I don’t mean to dismiss either the paper or this critique as being irrelevant, but it does seem that they have been overtaken by events. Data from more recent years ( see http://sealevel.colorado.edu/content/2014rel2-global-mean-sea-level-time-series-seasonal-signals-retained for example) strongly suggest that the Cazenave paper was at least broadly correct. Sea levels seem to have resumed their upward march now that the La Nina event is past.
To Mod; comment above posted on the wrong thread. Please delete.
Just occurred to me…. Shouldn’t they go back and also apply the corrections to the pre 1998 days? If they did, wouldn’t that once again show a decreasing rate of Sea level rise? Comparing corrected data to the uncoorected prior rate is dishonest.
I don’t mean to be dismissive either of the paper or this critique, since it’s important to figure out how sea level data should be analyzed in the context of other data, and models. But the basic conclusions of Cazenave’s paper do seem to be strongly supported by more recent data, which show that sea level has resumed its upward march: http://sealevel.colorado.edu/content/2014rel2-global-mean-sea-level-time-series-seasonal-signals-retained
we should forgive the alarmists,
http://discovermagazine.com/2010/jul-aug/29-why-scientific-studies-often-wrong-streetlight-effect
Why Scientific Studies Are So Often Wrong: The Streetlight Effect
Researchers tend to look for answers where the looking is good, rather than where the answers are likely to be hiding.
oh and spare a thought for Spain on Earth hour day, hope the electrics don’t fail them
Snowfall warning for Spain
A total of 24 provinces will be under hazard warning (yellow) or significant risk (orange) this Saturday
Gamecock says:
March 29, 2014 at 5:46 am
Gamecock, if you have EVIDENCE to back up your claim that the sea level data is affected by the changes in the mid-ocean ridge, this would be the time to bring it up … it’s an interesting hypothesis, but without data it’s not much use.
In any case, I doubt that the changes in the seafloor in 20 years are enough to make any difference in this analysis …
w.
Bill_W says:
March 29, 2014 at 6:50 am
I and some other folks have been pointing that out that people are dying as loud as we can. See for example “We Have Met The 1% And He Is Us” and James Hansen’s Policies Are Shafting The Poor” as examples.
The main point is not the assigning of blame or responsibility, however. The main point is that the insane war on carbon is impoverishing and killing the poor.
w.
It is almost “on any given day” Any Brazen Knave might put out a “study” in hopes of sucking in some money .
Sometimes they succeed, indeed…
george e smith says:
March 29, 2014 at 9:40 am
Good question, george. To measure the sea surface to 1 mm accuracy from a satellite 1,300 km above the surface you have to be precise to one part in 10^9 …
I assume that is among the reasons for the difference in e.g. the trends shown in Figure 1 as calculated by the five processing groups.
w.
It is not directly obvious, nonetheless there are implicit decisions and tough choices behind this paper.
Their grant contract is nearing it’s end and the grantor is asking about results plus the recipient organization is insisting on peer (cough, pal, cough, spouse) review published paper to bolster the organizations ranking.
Which is worse, after eighteen months of loose schedules, fine meals, fine residences and sun drenched trips; to be found with near zero research work or deliver a gobbledygook manifesto aiding the distraction claims for cause of the pause.
That’s easy, though not as easy as the eighteen months of good living, writ a quickie paper using math jargon, funky math and quintuple speech. Plus they need the paper to justify their current
(g)rant requests.
After all, what is one more dodgy paper amongst so many alarmist dodges; and they’re guaranteed alarmist cries of pleasure and blind veneration.
/sarc
Willis, if they are going to apply corrections to the recent satellite data to show that the increase is continuing at the same rate as it was earlier. Don’t they also need to apply those corrections to the earlier data as well if they want to have a valid comparison? What happens to the earlier data if they apply these same corrections to it as well? If these corrections, applied to the earlier data make it even more in disagreement with the tide gauge data, then I think that shows these corrections are likely inappropriate. To me, it’s kind of like a “Mike’s Nature Trick”, applying a correction only to a part of the data they don’t like.
rgbatduke says:
March 29, 2014 at 5:39 am “It’s a bit more complicated than that — ”
While globa laverage mean sea level rise may be more complicated than that. When it comes to what each specific area needs to prepare for, tide gauges are the only ones that matter because they are actually measuring the REAL change in sea level relative to that specific location.
For EX, if your local tide gauges are showing a decreasing sea level in your area with time, makes absolutely no sense to base your local laws and environmental policies assuming the area will be underwater in the near future. Same goes for the opposite…. if mean sea level was dropping but your local tide gauges show that there is rapid relative sea level rise occurring in this particular area, you better plan accordingly and NOT base you regulations on the decreasing MEAN sea level rise. So, in the end, it is the tide gauges that are the ONLY important measure with respect to policy. The rest is just a academic exercise.
Hello,
Sorry for being off topic, but your graphs Willis, they are almost always very clear, very nice looking, and combining different information, or using a background picture, in a way that melts in very well. What tool do you use for doing these nice looking graphs?
— Mats —
If the heat is hiding in the deep oceans, why has the sea volume (and hence its level) gone down in recent years? Options are: it’s evaporating more (which might be the case if there were greater surface temperatures), there is less fresh water feeding into it, or it is cooling.
“””””…..Willis Eschenbach says:
March 29, 2014 at 11:02 am
george e smith says:
March 29, 2014 at 9:40 am
I discovered, that you could not get very accurate results; dependent on measuring the actual optical length in air of this device. …..”””””
They do get a break, that I didn’t Willis, presumably, they use a laser probe, so at least they can forget the dispersion of the atmospheric refractive index.
In determining the optical length of the resonant cavity, in an FP etalon, you have to account for the fact that there is a non mechanical phase shift, on reflection, due to the optical parameters of the etalon reflecting mirrors, which was simply silver in my gizmo, but that translates into just another unknown in the optical length. You can resolve a small fraction of a wavelength, because of the sharp, multiple beam interference in the FP, whereas, a Michelson interferometer, gives you sinusoidal fringes, with a lot less fractional resolution. The problem is that you might be able to determine the fractional fringe to 0.01 wavelength (these days) but the mechanical uncertainty, could be ten wavelengths, due to micrometer accuracy.
The trick is, that by using a number of wavelengths, each giving some integer uncertainty in the fringe count, if you add the observed fractional fringe, to say a dozen sequential “guesses” at the integer fringe count, and do that for four or five wavelengths some distance apart, then only one of those guesses, will yield the same cavity length for all wavelengths, and that resolves the micrometer uncertainty.
Modern FPs with dielectric mirrors, have way more resolving power than the Edmunds Scientific, type of gizmo, we had in school.
Robert brown
Sure, the British do have centuries old ships quays. There is one some 400 years old a few hundred yards from my home. It’s very difficult to discern any sea level rise over several hundred years but levels are greatly complicated by the fact that land can be either rising or falling as a result of glacial action and this rise or fall is likely to be greater than the actual change in water volume caused by melting glaciers or thermal expansion. Global averages for sea levels are as nonsensical as global averages for land temperatures
Tonyb
There is a limit to how much heat you can hide in the deep ocean, because you are constrained by the thermosteric expansion coefficient of about 150-300ppm/°C, depending on pressure, salinity, and temperature, for almost all of the volume. If the rise of the oceans since 1900 at a fairly steady 2mm/year were 100% thermal expansion, with no melting glaciers, etc., then given the average ocean depth of about 4000m, 0.002m/4000m = 0.5ppm/year. That translates to a temperature change of 0.5ppm/(150-300ppm/°C) = 0.0033 to 0.0067°C/year. If you multiply that by the ocean volume of 1.37×10^9 cubic km at 1cal/degree/cc, and divide by the surface area of the Earth, you get (1.37×10^24 cc)(1cal/degree/cc)(4.184watts/(cal/sec))(0.0033 degrees/year)/(31,536,000 seconds/year)(5.1×10^14m2) = 1.18 – 2.36 W/m2.
So the extreme upper bound on the heat you can hide in the deep ocean that is consistent with the recent level of sea level rise, distributed over the globe, is about 1-2W/m2. The real number has to be less, probably quite a bit less. The IPCC estimates the total net anthropogenic forcing to be 1.5W/m2, so we are pushing the edge of the envelope of plausibility now. Continued failure of sea level rise to accelerate will invalidate the ocean as a hiding place for anthropogenic warming, if it hasn’t already been invalidated.
“Gamecock, if you have EVIDENCE to back up your claim that the sea level data is affected by the changes in the mid-ocean ridge, this would be the time to bring it up … it’s an interesting hypothesis, but without data it’s not much use.”
I can’t quantify that which the world’s scientists haven’t quantified.
http://en.wikipedia.org/wiki/Ocean_basin
“The Atlantic ocean and the Arctic ocean are good examples of active, growing oceanic basins, whereas the Mediterranean Sea is shrinking. The Pacific Ocean is also an active, shrinking oceanic basin, even though it has both spreading ridge and oceanic trenches.”
What is the net affect of these changes? No one knows.
The ocean basin is affected by tectonics, volcanism, and sedimentation. I say that the belief that these have no affect on sea level is the radical position.
http://www.ucmp.berkeley.edu/fosrec/Metzger3.html
“The creation of new sea-floor at mid-ocean spreading centers and its destruction in subduction zones is one of the many cycles that causes the Earth to experience constant change.”
http://www.nature.com/nature/journal/v278/n5700/abs/278161a0.html
“We show here that the mean annual load of suspended sediment at Óbidos, Brazil is between
8 and 9 × 10 8th tonnes yr−1”
If I didn’t mess up a zero, that’s 1.7 trillion pounds of material every year from the Amazon basin onto the continental shelf.
http://www.earthobservatory.nasa.gov/IOTD/view.php?id=1257
500 million tons a year for the Mississippi River.
http://eoimages.gsfc.nasa.gov/images/imagerecords/1000/1257/modis_mississippi_sed_lrg.jpg
I think I have reasonably proved the ocean basin is NOT a fixed size. Until it is measured in detail, and monitored for change, discussion of causes of changes in sea level is gross speculation. Focusing on water mass alone fails.
pnprice says:
March 29, 2014 at 10:34 am
Mmmm … well, not really. You’ve confused yourself by using the Colorado data with the seasonal trends included. You need to look at the same graph but with the seasonal variations removed …
What she is talking about is the kink that started in 2006, which is still clearly visible. Draw a line from the start to that hump and you’ll see the problem …
Let me recommend, however, that you actually run the numbers yourself, which are available here. Here’s a simple analysis. I’ve used 5-year centered trends just as they did.
As to the “basic conclusions” of the paper, I have no idea what they might be. What they did is take the data, add the difference between that and the models, and declare victory … which means that their basic conclusion is that models trump data.
Finally, I was stunned that they didn’t include any data on the actual El Nino over the time period in question. Their ostensible hypothesis was that the lack of sea level rise was due to El Ninos … why wouldn’t they look at that directly?
I just took a quick squint. I find no correlation between El Nino (using the Oceanic Nino Index) and sea level at any lag or lead. However, I find a correlation between El Nino and sea level trends. Comparing five year centered gaussian averages of El Nino and 5-year sea level trends, there is a negative correlation of -.5 between El Nino today and sea level trends two years later. Unfortunately, it’s a long ways from statistically significant, p=0.1 …
All the best,
w.
matsibengtsson says:
March 29, 2014 at 11:48 am
Thanks, Mats. Only Figure 3 in this is my graph, and it was done in Excel. I just add the background picture in Excel as a part of the chart.
I also do a number of graphs in my other tool of choice, the R computer language. It can do the heavy lifting numerically, but I’m still very much a beginner as far as my graphics there go … haven’t figured out yet how to put a background on an R char.
w.
Tonyb says:
March 29, 2014 at 12:18 pm
In your historical analyses of temperature data, have you perchance ever studied the frequency of super El Niños & La Niñas during the Medieval Warm Period & Little Ice Age Cold Period, as compared with the Modern Warm Period?
CACA advocates are fervently hoping & praying for another super El Niño this year:
http://thinkprogress.org/climate/2014/03/26/3417812/el-nino-extreme-weather-global-temperature/
Meanwhile, local sea levels keep on rising at about the same rate as usual since the Roman Warm Period. Australia seems to me a good place to study sea level changes, as it wasn’t heavily glaciated even during the LGM.
UnfrozenCavemanMD says:
March 29, 2014 at 12:23 pm
Dang … I do admire a man who runs the numbers himself.
And I particularly like the idea of bounding the thermal gain using the steric expansion. I’ll have to look into that, unless you beat me to it.
w.
And we’re given this from the International New York Times:
http://www.nytimes.com/2014/03/29/world/asia/facing-rising-seas-bangladesh-confronts-the-consequences-of-climate-change.html?ref=world&_r=0
Has the world gone insane?
This global warming thing is the equivalent of the Salem Witch Trials, only more people are being killed as a result (e.g., winter deaths in GB due to expensive power caused by….).
Deep sea heat? Well there is a bit of proof that deep sea vents do throw out hotter water, and the life around them exists on chemosynthesis, rather than photosynthesis. Anyway that is restricted to around volcanic vents and trenches. But the volume of the cold water soon cools it down.
I have often wondered what a persistent high pressure system does to sea levels when over the water for an extended period of time.
Just a thought.
Nice read Willis!
” Global averages for sea levels are as nonsensical as global averages for land temperature”
both averages make perfect sense.
Gamecock says:
March 29, 2014 at 12:39 pm
Fair enough …
Fair enough.
Thanks for the information and the links, Gamecock. The question is not whether the ocean basin size varies. Everyone knows it varies. The question is, does it vary enough to make a difference?
For this analysis, the question is whether the variation in basin size will make a visible difference over the 18 years of the record. Or even over the hundred years or so of the tide gauge record.
For example. You point out that the Amazon puts call it 9e+8 tonnes of suspended sediment into the ocean annually. Globally, the total sediment added is estimated to be on the order of 15e+9 tonnes. Density of the silt is on the order of 2 tonnes/km3, so that is about 7.5e9 cubic metres, or 7.5 cubic kilometres of ground-up rock and soil.
Now, the ocean area is about 3.5e+8 square kilometres … so the 7.5 cubic km of rock and soil added by all the worlds rivers and all the floods and all will raise the ocean by about
7.5 / 3.5e+8 * 1e+6 mm/km = 0.02 mm per year …
Like I said, the question is not whether, but how much …
All the best,
w.
ossqss says:
March 29, 2014 at 6:59 pm
Your intuition is good. In some cases, when studying sea levels researchers use an “inverse barometer” correction to account for exactly that effect, where high pressure pushes down on the ocean surface.
Here’s a back-of-the-envelope estimate. Total weight of the atmosphere is about 10 metres of water or so. Normal range of barometric pressure is about 980 to 1050 mbar (hPa), or about a ± 3.5% swing. Typical pressure moves are more on the order of ±1%, and 1% of 10 metres is 10 cm, or about 4″. So yes, pressure variations definitely move the surface of the ocean up and down, a 1% change in pressure is equivalent to a change in weight of 4″ of water.
w.
Wills
Another factor that I don’t see mentioned is how much water is bound up in plants? Since, according to several studies, the planet has greened by 30% due to carbon fertilization since the 1960’s, that would imply greater water storage in the floral system.
The question of the contribution of erosion and tectonics to SLR could use a philosophical perspective. One consideration: how much water is rained down on the earth from space? How much space dust? Both are surely trivial, but space dust is not only trivial but irrelevant, since it should be spread evenly over the planet, raising ocean and land evenly. Space water, on the other hand, would only raise sea level.
Ignoring ice and thermal expansion, that is, considering only depth and elevation distribution, it should at least be noted that the continents have always floated on the mantle, and while subduction of the continents does occur, it is reasonable to assume that they resurface at an approximately equivalent rate. Likewise the same plate tectonics that alter the width and depth of ocean basins simultaneously build mountain ranges, and the same sedimentation that builds the continental shelves results in uplift of the plateaus and river basins from which the sediment is removed.
In other words there is little reason to believe that over the long run geological processes make much difference in SLR, let alone over decades. The earth has never been flat, mountains are always growing, and gravity and erosion limit their height.
The separate question as to SLR serving as a thermometer is complicated by a few factors that need mentioning. For one thing, it takes about two orders of magnitude more energy to raise SL through expansion than through melting land ice, so that the relative contribution of each must be known before we can calibrate. Also, since thermal expansion of seawater varies by temperature, pressure, and salinity–significantly–we have to know at what depth and temperature the expansion is taking place before we can calculate energy input from steric SLR. Obviously with ARGO it’s easier to calculate in the other direction.
Through the Pleistocene there has been obvious correlation between SLR and T, but it is not a case of cause and effect with T as cause. Rather the reverse is closer to the truth, since SLR is a function of ice volume, and T is a function of albedo, or ice area. Therefore T/SLR corresponds to ice area/ice volume, on a Pleistocene secular scale. –AGF
Willis Eschenbach says:
March 29, 2014 at 7:24 pm
A couple of papers along these lines
http://onlinelibrary.wiley.com/doi/10.1029/2007GL030862/abstract
Gyre-scale atmospheric pressure variations and their relation to 19th and 20th century sea level rise
Laury Miller1 andBruce C. Douglas2
http://www.ocean-sci.net/6/185/2010/os-6-185-2010.pdf
The gyre-scale circulation of the North Atlantic and sea level at
Brest
P. L. Woodworth1 , N. Pouvreau2, and G. Woppelmann ¨
mosh said in reply to me
” Global averages for sea levels are as nonsensical as global averages for land temperature”
He said ‘both averages make perfect sense.”
In that case it should be very easy for you to explain them.
They make as much sense as the average for global economic growth which ignores that some areas remain in recession whilst others are powering ahead. You will set economic policy according to what is happening in your own country/region not what is happening elsewhere
Surely it is more useful to look at what is actually happening in the real world rather than at some averaged one which doesn’t exist?
But look forward to your detailed article. A good title would be ‘One size does fit all.’
tonyb
Willis Eschenbach says:
March 29, 2014 at 7:10 pm
The question is not whether the ocean basin size varies. Everyone knows it varies. The question is, does it vary enough to make a difference?
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I have never, ever heard anyone mention variability of the ocean basin. All discussions of sea level are about water only.
Does it vary enough to make a difference? We simply don’t know.
rgbatduke says:March 29, 2014 at 9:57 am
Thank you for your expansion of my thought. Although TonyB responded to your query of ancient harbor’s sea level, he didn’t point to his sites post @ http://climatereason.com/Articles/
Third article down, entitled ‘A Look at Historic Sea Levels’, by Tony Brown, with links.
Gamecock says:
March 30, 2014 at 8:59 am
I have never, ever heard anyone mention variability of the ocean basin. All discussions of sea level are about water only.
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Three years ago UofC adjusted SLR 10% upwards for GIA, which is vertical change in ocean basin. Where were you?
http://wattsupwiththat.com/2011/05/05/new-sea-level-page-from-university-of-colorado-now-up/
–AGF
Gamecock says:
March 30, 2014 at 8:59 am
Dang, I wouldn’t boast about not doing your homework … so you missed e.g. the big furor when the radar satellite guys decided to add 0.3 mm/yr to account for that very change? See here for details.
I must say, people making this kind of statement without the simplest Google search are a scientific nuisance. You seem to think scientists are all idiots. The changes in the volume of the basins have been studied for years, see e.g. here, a document from a course by Judith Curry at the University of Georgia. There’s a whole section in that paper entitled “Sea Level Change due to Changing Volume of the Ocean Basin” … your claim, that you’ve discovered some new unstudied phenomena, doesn’t withstand even the slightest scrutiny.
w.
tonyb says:
March 30, 2014 at 12:03 am
I would disagree with mosh entirely. Sea level is an extensive property (a property which changes with the amount of material involved), while temperature is an intensive property. The averages of the two are quite different in both theory and practice.
However, I’d agree with him that there are many purposes for which such averages do indeed make perfect sense.
I don’t understand this objection. While it is true that averages don’t exist, that doesn’t mean that they are useless. Consider for example the grade-point-average (GPA) for a student. How is that not useful in measuring how well a student is learning? And how is that GPA not “what is actually happening in the real world”?
Look, tonyb, I’m one of the researchers who dislikes averages the most, they are often misused and can hide lots of interesting phenomena.
But that doesn’t mean that they are not useful when properly used.
w.
Willis
Of course averages are useful in some cases.
I was particularly concerned with the worth of global averages for something as local as sea temperatures, and land temperatures and sea levels. By averaging we are missing out on useful nuances whereby for example not all the world is warming and not all the sea in its various basins is rising, indeed in some areas sea level is falling whilst in others it is rising much faster than ‘average,’
Tonyb
Willis, if you want to explore bounds on thermal gain using steric expansion, I recommend this reference: http://publishing.cdlib.org/ucpressebooks/view?docId=kt167nb66r&chunk.id=d3_4_ch03&toc.id=ch03&toc.depth=1&brand=eschol&anchor.id=tab009#X. I also checked my numbers against Levitus et al [GRL 2012].
Levitus et al [GRL 2012] estimate the 55 year trend of ocean thermal gain (1955-2010) to be 0.4W/m2 over the entire ocean volume, which is much less than 1.5W/m2, but theoretically could have increased in the last 16 years of flat lower tropospheric temperatures. They correspondingly estimate less of a thermosteric component of sea level rise, at 0.54mm/y which means that my back-of-the-envelope upper bound of 2mm/y sea level per 1 – 2 W/m2 heat storage (1-2mm/W/m2) agrees with Levitus et al’s number of 0.54mm/y/0.4W/m2 (1.35mm/W/m2).
Since implicit in Levitus is 1.35mm of sea level rise per W/m2 of ocean-stored global forcing, and the IPCC estimates net anthropogenic forcing to be 1.5W/m2. That comes out to just about exactly 2mm/y of sea level rise if it all goes into the ocean. If the current rate is 3mm/y, that leaves only 1mm/y for the natural post LIA rise plus all the anthropogenically melted glaciers.
Willis writes “Consider for example the grade-point-average (GPA) for a student. How is that not useful in measuring how well a student is learning?”
I think you missed the point. Consider for example the grade-point-average (GPA) for all students. How is that useful in measuring how well a student is learning?
I’ve subtly rewrittewn your statement so you can see his point.
TimTheToolMan says:
March 30, 2014 at 7:24 pm
Recall that his comment to which I was responding was in reference to sea level measurements:
I was simply point out that looking at sea level averages can be valuable, just as looking at individual sea levels can be valuable.
Next, you ask:
He said that averages of sea levels are not useful, and that it’s more valuable to look at “what is actually happening” … as though averages weren’t part of what is happening …
I gave a simple example to show that averages are useful.
You’ve twisted my words around so that they mean something totally different, ostensibly so I can “see his point” … sorry, but that doesn’t make sense. I have no clue what you are getting at. Likely my mistake, my lack of understanding, but I’m just not getting it. Far too roundabout for me.
If you’d just stand up and say “Willis, here is his point that you missed” that might be useful.
w.
Willis writes “Recall that his comment to which I was responding was in reference to sea level measurements:”
Because you ignored his argument.which was “You will set economic policy according to what is happening in your own country/region not what is happening elsewhere. Surely it is more useful to look at what is actually happening in the real world rather than at some averaged one which doesn’t exist?”
I dont think you understood. His point was about the importance of local effects not whether there was any use for a global average at all. Your example specifically didn’t address what I would consider his main point.
TimTheToolMan says:
March 30, 2014 at 11:34 pm
I “ignored” it? So you know what I’ve looked at and noticed, and what I haven’t noticed and what I’ve ignored? Your claims about your grandiose omniscience are risible—how on earth would you know what I’ve seen and what I haven’t seen?
I didn’t ignore a damn thing. I didn’t understand his point the way you understood it. So sue me.
Oh, now I didn’t “ignore his argument”, now I didn’t understand it? If you’re going to be a jerkwagon, at least be consistent.
Tim, his point was clear and succinct. He said:
I thought then that he was wrong about that. I still think so. If you think he is right, then please explain why.
Now his explanation (as you point out) was that averages are nonsensical because some areas are going up and some areas are going down … do you really believe that? To be specific, his claim was that an economic average is “nonsensical” because “some areas remain in recession whilst others are powering ahead” … seriously Tim, do you believe his explanation that averages are “nonsensical” because of the things being averaged, some are high and some are low?
Does that explanation really work for you?
Because it makes no sense to me at all, and that was assuredly his claim. Didn’t make sense then, doesn’t now.
w.
Willies writes “If you’re going to be a jerkwagon, at least be consistent.”
Thanks for the abuse Willis.
Willis writes “Now his explanation (as you point out) was that averages are nonsensical because some areas are going up and some areas are going down … do you really believe that?”
I dont know about “going down” but certainly its very well known that sea level rise differs regionally and so it makes sense for local authorities to be looking at their regional changes when considering policy rather than focussing on the global average. He made that point and its a fair one.
You ignored it entirely and instead focussed on your own interest area. Fine. I expect nothing less from you actually.
TimTheToolMan says:
March 31, 2014 at 3:36 am
Tim, re-read the thread. Things were going quite nicely until you accused me of malfeasance, saying that I deliberately was ignoring what someone was saying. You might get away with that kind of bs with your friends, but I can guarantee that when you try it on me, it will blow up in your face every time.
Certainly sea level differs regionally. However, any local authority that thinks that they can make decisions based solely on the local changes and ignore the overall average changes is an idiot. Why? Because eventually all of the local areas are likely to revert to the mean … and if you don’t know what that mean is, how can you prepare for it?
You need both local and global knowledge to make an informed decision, not just one or the other.
And in any case, even if you don’t need average sea levels for some given task, it doesn’t make average sea levels “nonsensical” as he fatuously claimed. Since when have averages become “nonsensical”, and why didn’t I get the memo?
Look, Tim, unless you’ve suddenly developed ESP you don’t have a clue what I am “ignoring”, you have no way to tell what I ignored from what I didn’t notice, and you have no means to distinguish either of those from what I simply decided was not important enough to comment on. That means you’re just making this stuff up to cause trouble. Have you always been like that, or is it a skill that you’ve developed and honed over time?
I objected strongly last time you falsely accused me of “ignoring” things. Like I said, it will blow up in your face every single time you try those false accusation.
It was a sleazy underhanded move the first time you failed to run it past me. Now, the second time you blindly accuse me of ignoring something, it has all the hallmarks of a deliberate insult.
Let me invite you to gently place your ugly insinuations where the total solar irradiance (TSI) is zero …
w.
Willis writes “Tim, re-read the thread. Things were going quite nicely until you accused me of malfeasance, saying that I deliberately was ignoring what someone was saying. ”
Good idea.
Tim writes “I think you missed the point.”
Well there’s a hateful comment telling you you were ignoring something. That was bound to start an abusive argument from you. And it did.
And then you wrote _rant_ including calls of omniscience and ESP regarding my “understanding” of what you ignored. Well what you ignored was what you didn’t reply to…otherwise, yes ESP would have to be involved. Followed by “I have no clue what you are getting at. Likely my mistake, my lack of understanding, but I’m just not getting it. Far too roundabout for me.”
And you wonder why I said I thought you didn’t understand?
I do love your rants though. This… “You might get away with that kind of bs with your friends, but I can guarantee that when you try it on me, it will blow up in your face every time.” …is gold.
The long tail of the Great Melt would be expected to go asymptotic to a 0 slope. And at some point it will go negative as the Continental Ice builds back up at the end of the Interglacial.
TimTheToolMan says:
March 31, 2014 at 4:58 am (Edit)
Tim, I think you missed my point.
It is not a neutral act to accuse a man of ignoring something, particularly in your case, because you do not have a clue whether I even read what you are accusing me of ignoring.
I might have read it and not understood it. I might have overlooked it entirely, I might have read it and not had any answer. I might have read it and been unclear on the main points. I’m juggling a lot of comments at any given instant, and no, I don’t read or understand everything, Tim. So sue me … but don’t blindly and falsely accuse me of ignoring something. Doing that is not “hateful”, as you claim. It is simply very insulting. I’m an honest man, Tim. I don’t play those kinds of childish games, and I don’t appreciate being accused of doing so.
Now, like I said, perhaps your friends don’t object when you try this kind of an insult out on them. I said that because you don’t even seem to realize that it is an insult to some people. So that would imply that your friends either don’t object or don’t notice when you make that kind of unsupported accusation.
Or perhaps you only try running this kind of insult past me, and you don’t do it with your friends.
For whatever reason, you seem to think that it is perfectly fine to accuse a man of deliberately ignoring something, without the slightest scrap of evidence to back up that nasty claim. It is not perfectly fine to do that anywhere I’ve ever been …
And yes, Tim, every time you try to do it to me, it will bite you back. And it seems that you know that, since you said “That was bound to start an abusive argument from you. And it did.”
Charming. You deliberately did something, knowing that I would slap your face for it … I give up, Tim. No more for me, that’s all I can take of TimTheTool. I don’t deal with folks who deliberately do things that they admit they knew were bound to start trouble, as you just have.
w.
Willis writes “For whatever reason, you seem to think that it is perfectly fine to accuse a man of deliberately ignoring something, without the slightest scrap of evidence to back up that nasty claim. ”
Evidence? You didn’t reply to his point. I thought you didn’t understand and from your posts its pretty obvious that was the case. So when I point that out I’m being somehow abusive. Had you ever stopped to think that perhaps you’re overly sensitive to having people point those kinds of things out?
Willis writes “No more for me, that’s all I can take of TimTheTool.”
At no point have I ever insulted you. But hey, your colours sure do shine in this thread!
TimTheToolMan says:
March 31, 2014 at 2:28 pm
Tim, it seems you do not understand what it means when you accuse someone of ignoring something. You seem to think that it means to overlook something. Let me try giving you some examples:
Kids ignore what their moms said when they want to play in the street.
Scofflaws ignore the court summons.
Bad companies ignore repeated requests from customers.
Speeders ignore the speed limits.
Note that e.g. the companies are not overlooking repeated requests. That would be blameless.
But when the companies ignore repeated requests, well, that is wrong, n’est-ce pas? So saying that they ignore the repeated requests is an ACCUSATION, Tim. It’s not some bland statement like you seem to think.
Now, what is the common thread in all of these? Well, when we say that someone is “ignoring” something, we mean that it is willful—the person KNOWS THAT THEY ARE DOING WRONG, and THEY IGNORE THAT FACT AND DO IT ANYWAYS.
That’s why you saying that I ignored the man’s point is not a neutral comment. It means that
a) I’d read his point, and
b) I’d understood his point, and
c) I knew that he was right and I was wrong, but
d) I was unwilling to address it, so I simply ignored it and tried to brazen it out.
Now, as I pointed out above, you didn’t have a scrap of evidence that any of that was true. You didn’t even know if I’d read it, Tim, when you falsely claimed that I’d ignored it. That’s how far your fantasies extend.
Not only that, by your own admission you did it deliberately. Here’s what you said about your comment:
So you did it deliberately … and you still believe you have the high moral ground?
As to whether my colors shine in this thread, I’d say that my colors are clear—I don’t suffer fools gladly, and I will not stand by idly when some random internet popup wants to falsely accuse me of something about which they know nothing …
What do you do when that happens, Tim, or Jim, whatever your name might be? Do you just stand there and let your reputation be rubbished by some jerk who never met you and yet thinks they know what you have and haven’t read?
w.
Willis writes …
Overreaction much?
When you post about one point another poster makes and not their main point then you have ignored their main point. Pure and simple. What you think you read or understood is entirely irrelevant.
But on the upside, your rant on the evils of ignoring is also gold.
TimTheToolMan says:
April 1, 2014 at 5:02 am
Naw, you reacted just about like I expected you to, given your past history.
Gosh. So at the end of the day, your remaining claim is that even if I never read their main point I’ve “ignored” it, “pure and simple”?
That’s too good, Jim. Or Tim. Or whatever your name is. However, I must say I’m sorry, but I won’t take lessons in bad English from an anonymous internet popup who is unwilling to stand behind his own words … if you don’t have what it takes to sign your own name to your own words, why should I pay the slightest attention to your anonymous opinions on my words?
w.