Dialing back the 10 foot hype – NOAA Tide Gauge Data shows no coastal sea level rise acceleration

… meanwhile California sea level rise “model study” claims 10 foot rise by 2100

Guest essay by Larry Hamlin

NOAA has just updated its coastal sea level rise tide gauge data including actual measurements through year 2016 which continues to show no evidence of coastal sea level rise acceleration.

These measurements include tide gauge data coastal locations for 25 West Coast, Gulf Coast and East Coast states along the Pacific Ocean, Gulf of Mexico and Atlantic Ocean, 7 Pacific island groups and 6 Atlantic island groups comprising more than 200 measurement stations.

The longest NOAA tide gauge data coastal sea level rise measurement record is at The Battery in New York with its 160 year long data record showing a steady rate of sea level rise of about 11 inches per century.

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NOAA data provides assessments of the 95% confidence intervals at all measured locations which demonstrate the consistent behavior of location specific sea level rise over time and as well as showing that longer interval measurement periods provide tight ranges for the 95% confidence interval.

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The 2016 updated NOAA tide gauge data includes four long time period (between 92 and 119 years) coastal locations for California at San Diego, La Jolla, Los Angeles and San Francisco. The actual measured and steady coastal rates of sea level rise at these locations vary between about 4 to 9 inches per century.

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The UN IPCC AR5 WG1 report concludes in the Summary for Policymakers Chapter that:

“It is very likely that there is a substantial anthropogenic contribution to the global mean sea level rise since the 1970s. This is based on the high confidence in an anthropogenic influence on the two largest contributions to sea level rise, that is thermal expansion and glacier mass loss. {10.4, 10.5, 13.3}”

NOAA tide gauge coastal sea level rise data measurements encompassing the 46 year period from 1970 through 2016 do not support and in fact clearly contradict the UN IPCC AR5 WG1 conclusion regarding supposed man made contributions to increasing rates of sea level rise since the early 1970s.

Meanwhile here in California, the climate alarmist capital of the U.S.,  the Working Group of the Ocean Protection Council Science Advisory Team, supported and convened by California Ocean Science Trust have just released a new report Rising Seas in California, An Update on Sea–Level Rise Science which is intended to provide statewide sea-level rise policy guidance.

The report has been widely hyped by climate alarmist main stream media  http://www.mercurynews.com/2017/04/30/oceans-rising-faster-than-scientific-forecasts/  based on the highly speculative and scientifically unsupported claim that sea levels at the states coastline could rise by 10 feet by the end of the century.

The new state report is based on projections derived from semi-empirical climate models which supposedly provide probabilistic assessments of coastal sea level rise for California locations.

The UN IPCC AR5 WG1 report dealt extensively with the many problems and shortcomings of sea level rise semi-empirical climate models (SEM’s) and provided a litany of significant and complex unresolved scientific issues.

Provided below are IPCC identified issues with SEMs as noted in various chapters of the AR5 WG1 report.

Summary for PolicyMakers Chapter:

“The basis for higher projections of global mean sea level rise in the 21st century has been considered and it has been concluded that there is currently insufficient evidence to evaluate the probability of specific levels above the assessed likely range. Many semi-empirical model projections of global mean sea level rise are higher than process-based model projections (up to about twice as large), but there is no consensus in the scientific community about their reliability and there is thus low confidence in their projections. {13.5}”

Technical Summary Chapter:

“Semi-empirical models are designed to reproduce the observed sea level record over their period of calibration, but do not attribute sea level rise to its individual physical components. For RCPs, some semi- empirical models project a range that overlaps the process-based likely range while others project a median and 95-percentile that are about twice as large as the process-based models. In nearly every case, the semi-empirical model 95th percentile is higher than the process-based likely range. For 2081–2100 (relative to 1986–2005) under RCP4.5, semi-empirical models give median projections in the range 0.56 to 0.97 m, and their 95th percentiles extend to about 1.2 m. This difference implies either that there is some contribution which is presently unidentified or underestimated by process-based models, or that the projections of semi-empirical models are overestimates.”

“Making projections with a semi-empirical model assumes that sea level change in the future will have the same relationship as it has had in the past to RF or global mean temperature change. This may not hold if potentially nonlinear physical processes do not scale in the future in ways which can be calibrated from the past. There is no consensus in the scientific community about the reliability of semi-empirical model projections, and confidence in them is assessed to be low. {13.5.2, 13.5.3}”

“There is low confidence in semi-empirical model projections of global mean sea level rise, and no consensus in the scientific community about their reliability. {13.5.2, 13.5.3}”

Sea Level Change Chapter 13: 

“Some semi-empirical models project a range that overlaps the process-based likely range while others project a median and 95th percentile that are about twice as large as the process- based models. In nearly every case, the semi-empirical model 95th percentile is higher than the process-based likely range.”

Despite the successful calibration and evaluation of semi-empirical models against the observed 20th century sea level record, there is no consensus in the scientific community about their reliability, and consequently low confidence in projections based on them. {13.5.2, 13.5.3, Figure 13.12}”

“Semi-empirical models (SEMs) project sea level based on statistical relationships between observed GMSL and global mean temperature (Rahmstorf, 2007a; Vermeer and Rahmstorf, 2009; Grinsted et al., 2010) or total RF (Jevrejeva et al., 2009, 2010). The form of this relationship is motivated by physical considerations, and the parameters are determined from observational data—hence the term ‘semi-empirical’ (Rahmstorf et al., 2012b).”

“SEMs do not explicitly simulate the underlying processes, and they use a characteristic response time that could be considerably longer than the time scale of interest (Rahmstorf, 2007a) or one that is explicitly determined by the model (Grinsted et al., 2010).”

“The semi-empirical approach regards a change in sea level as an integrated response of the entire climate system, reflecting changes in the dynamics and thermodynamics of the atmosphere, ocean and cryosphere; it does not explicitly attribute sea level rise to its individual physical components. SEMs use simple physically motivated relationships, with various analytical formulations and parameters determined from observational time series, to predict GMSL for the 21st century (Figure 13.12 and Table 13.6) and beyond, from either global mean SAT (Rahmstorf, 2007a; Horton et al., 2008; Vermeer and Rahmstorf, 2009; Grinsted et al., 2010; Rahmstorf et al., 2012b) or RF (Jevrejeva et al., 2009; 2010, 2012a).”

“The GMSL estimates used for calibrating the SEMs are based on the existing sparse network of long tide-gauge records, and are thus uncertain, especially before the late 19th century; these uncertainties are reflected in the observational estimates of the rate of GMSL rise (Sections 3.7 and 13.2.2).”

“Consequently, the projections may be sensitive to the statistical treatment of the temporal variability in the instrumental record of sea level change (Holgate et al., 2007; Rahmstorf, 2007b; Schmith et al., 2007). Rahmstorf et al. (2012b) reported that GMSL projections for the RCP4.5 scenario for 2100 (Table 13.6) varied by ±0.04 m when the embedding dimension used for temporal smoothing during the calibration was varied within a range of 0 to 25 years.”

“SEM projections will be biased unless contributions to past GMSL rise which correlate with but are not physically related to contemporary changes in the predictor variable (either global mean SAT change or RF) are subtracted from the observational sea level record before the cali- bration (Vermeer and Rahmstorf, 2009; Jevrejeva et al., 2012b; Rahm- storf et al., 2012b; Orlić and Pasarić, 2013).

“These include groundwater depletion due to anthropogenic intervention and storage of water by dams (Section 13.3.4), ongoing adjustment of the Greenland and Ant- arctic ice sheets to climate change in previous centuries and millen- nia (Section 13.3.6), and the effects of internally generated regional climate variability on glaciers (Marzeion et al., 2012a; Church et al., 2013, Sections 13.3.2.2 and 13.3.6) and ice sheets (Section 13.3.3.2). For instance, Jevrejeva et al. (2012b) found that their median projections for 2100 were reduced by 0.02 to 0.10 m by excluding some such contributions.”

“Making projections with a SEM assumes that sea level change in the future will have the same relationship as it has had in the past to RF or global mean temperature change. The appropriate choice for the formulation of the SEM may depend on the nature of the climate forcing and the time scale, and potentially nonlinear physical processes may not scale in the future in ways which can be calibrated from the past (von Storch et al., 2008; Vermeer and Rahmstorf, 2009; Rahmstorf et al., 2012b; Orlić and Pasarić, 2013). Two such effects that could lead to overestimated or underestimated projections by SEMs have been discussed in the literature.”

“The higher estimates from the SEMs than the process-based models used here for the long-term projections are consistent with the relation between the two modelling approaches for the 21st century (Figure 13.12).”

“Section 13.5.3 concluded that the limited or medium evidence supporting SEMs, and the low agreement about their reliability, provides low confidence in their projections for the 21st century. We note here that the confidence in the ability of SEMs is further reduced with the length of the extrapolation period and the deviation of the future forcing from the forcing of the learning period (Schaeffer et al., 2012), thus decreasing confidence over the long time frames considered here.”

The California main stream media climate alarmist articles about the new sea level rise study projections ignored these many thorny issues.

The new state sea level rise report contains many significant qualifications and uncertainties that are addressed but none of which are revealed by California main stream media alarmist articles.

Regarding the headline grabbing 10 foot sea level rise claim which is based on accelerated Antarctica ice melt the report notes the following:

“These projections may underestimate the likelihood of extreme sea-level rise, particularly under high emissions scenarios, so this report also includes an extreme scenario called the H++ scenario.”

“The probability of this scenario is currently unknown, but its consideration is important, particularly for high-stakes, long-term decisions.”

“Before 2050, differences in sea-level rise projections under different emissions scenarios are minor but they diverge significantly past mid- century. After 2050, sea-level rise projections increasingly depend on the trajectory of greenhouse gas emissions. For example, under the extreme H++ scenario rapid ice sheet loss on Antarctica could drive rates of sea-level rise in California above 50 mm/year (2 inches/year) by the end of the century, leading to potential sea-level rise exceeding 10 feet. This rate of sea-level rise would be about 30-40 times faster than the sea-level rise experienced over the last century.”

“As described above (Section 3.1.1), these projections may underestimate the probability of extreme Antarctic ice loss, an outcome that is highly uncertain but, given recent observations and model results, cannot be ignored.”

“Accordingly, we have also included an extreme sea-level rise scenario, which we call the H++ scenario. This is an unknown probability, high consequence scenario such as would occur if high rates of Antarctic ice loss were to develop in the last half of this century. When decisions involve consequential infrastructure, facilities or assets, we advise that extra consideration be given to this upper end of potential sea-level rise outcomes”

“The obvious question is: how confident can we be in the recent model projections? First, it should be emphasized that the model ensembles (Figure 10) hinge on the performance of a single ice-sheet model and a single climate model. Furthermore, the ensembles do not explore the full range of parameters in the ice sheet model.Thus, the ensembles do not provide a true probabilistic assessment of Antarctica’s possible future.”

“While much progress observing and modeling the ice sheet has been made in recent years, the precise magnitude and timing when Antarctic might begin to contribute substantial sea level should still be considered deeply uncertain.”

“Regardless of uncertainty in model physics, one of the greatest sources of uncertainty lies in which future greenhouse gas scenario will be followed; so even if the physical model were perfect in its representation of the natural world, there would still be major uncertainty in the Antarctic ice sheet’s future.”

The alarmist claims of 10 foot California sea level rise by the end of the century suggested by this report and highlighted by the media have no established scientific basis and represent nothing but conjecture and speculation.

Regarding the reports projections in general the following significant uncertainties are addressed:

“For projections over the next few decades, we do not expect the role of models and scenarios to be as crucial to pin down. However, as we move into the more distant future, our ability to guess what society will do diminishes, different models will be more or less dependable, and the processes generating our extreme scenario will unfold.”

“As a result, our ability to quantify uncertainty through formal probability distributions decreases. We therefore include a qualitatively different scenario (H++) whose likelihood we cannot characterize at this time, and note that quantified probabilistic projections need to be taken as an evolving representation of our understanding, open to updates and modifications especially in the tails of probability distributions. In this context of likely continued and unquantifiable uncertainties, incorporating long-range planning for sea-level rise in decisions is increasingly urgent.”

“Depending on the time horizon being considered, different sources of uncertainty play smaller or larger roles in projections of sea-level rise [48]. For long-term changes (second half of this century and beyond), the choice of model and scenario of anthropogenic greenhouse gas emissions significantly affect the outcome. By comparison, for short- to mid-term projections (within the next two or three decades), variability in the Earth’s climate system, which would exist even in the absence of human-driven changes, is the predominant source of uncertainty.”

“As for climate system drivers at large (e.g., ENSO, storms), the question boils down to assessing possible future changes and their statistical characteristics. At the moment, uncertainties in modeling outcomes are large and there is not robust evidence that the internal variability of these phenomena will change significantly under future scenarios [52]. As mentioned, the interplay of these different sources of uncertainty is not unique as we move from short- to mid- to long-term horizons for our projections.”

“Estimated probabilities of particular outcomes are increasingly less robust — in the sense of comprehensively covering the range of expected outcomes and firmly quantifying their relative probability — as we lengthen those horizons, and we move into climate scenarios of unprecedented nature as far as anthropogenic forcing is concerned”

The states new sea level rise report may be intended to provide California coastal sea level rise policy guidance but the very significant qualifications, limitations and uncertainties reflected in the report but unaddressed by the climate alarmist media clearly demands that planning efforts utilizing the reports projections must be done with great caution.

This is particularly true given the extensive NOAA coastal sea level tide gauge data for California locations showing no evidence of coastal sea level rise acceleration despite the claims of the UN IPCC that man made actions have been increasing the rate of sea level rise since the early 1970s.

[UPDATE] As these things happen, I’d written about this sea level question and was about to post it, but Larry has done it first, and likely better. I trust he won’t mind my adding one graphic from my now superceded post showing what the sea level would have to do to get to a ten foot rise by the year 2100 …sea level rise alarm sf 2100

And from my now unnecessary post …

How can any rational human being believe this kind of nonsense? The CO2 has been rising strongly since about 1940 or so … but in that 75 year period, the rate of sea level rise is basically unchanged. If CO2 were going to do something to sea level rise, it would have happened long ago.

I weep for the death of science … of course, this claim will be used to force people to do all kinds of crazy things if they want to build near the coast.

My best to all, and my thanks to Larry for an excellent exposition.

w.

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156 thoughts on “Dialing back the 10 foot hype – NOAA Tide Gauge Data shows no coastal sea level rise acceleration

  1. There will be a sudden increase in water levels like in this video.

    Must happen else the predictions will be proven incorrect!!!

    Cheers

    Roger

    http:/www.thedemiseofchristchurch.com

    • But in Florida there science denier govenor has given the go ahead to increase the hight of roads because the old roads were flooding on a regular basis making it impossible for cars. Google it, it’s shows how rising sea levels are causing havoc.

      • “Science”. You keep using that word, but I don’t think you know what it really means.

      • The oceans have risen about 1/2 an inch since those roads were built Steve. Trying checking in with reality before posting.

      • Steve, that’s not due to rising sea levels. It’s gross mismanagement of your groundwater causing large scale subsidence throughout the state. You are literally sinking because you’ve drawn so much water out of the ground that the state is settling down.

        This is why Texas created the Subsidence Districts in a number of counties (including my own home of Harris County) to manage water wells. We stopped overdrawing groundwater, so we stopped sinking into the Gulf.

        9 times out of 10, when someone blames a local problem on global warming, it’s a mask for incompetence or negligence of people who really should know better.

      • ‘their’ ‘governor’ is replacing roads that were built below sea level to begin with, and yes the land has been sinking there for centuries

      • It’s well known that the Floridian aquifer is being hit hard for water and that the land is subsiding as a result. Probably also causing all the sudden sink holes as well.

      • Some quick documentation of coastal land subsidence courtesy of the U.S. Government doing actual science:
        https://www.ngs.noaa.gov/heightmod/NOAANOSNGSTR50.pdf
        ” The analysis was accomplished using first-order leveling data and GPS observations from the National Geodetic Survey (NGS) and water level (tide gauge) data from the National Ocean Service.
        This study computed vertical velocities for over 2700 NGS benchmarks based on leveling data collected between 1920 and 1995. Subsidence affects coastal areas of Louisiana, Mississippi, Texas, and Alabama. The highest rates, over 25 mm per year, occur in the Mississippi river delta region and chenier plain of southwest Louisiana.”…
        …”We draw two primary conclusions from this study. First, subsidence is occurring at substantially higher rates than previously reported. These new rates provide insights into the causes of subsidence and should be integrated into plans to mitigate the effects of subsidence and the resultant inundation of coastal lands.”

      • By the way, coastal subsidence from groundwater and oil extraction IS a problem for those people who live there. Just make sure your attribution is to the correct cause.

        Species Homo sapiens, mostly sap.

  2. If “moon-beam” Jerry Brown wasn’t convincing 37,000,000 California tax-payers to jump off the “10 foot sea rise by 2100” cliff, this would be funny.

    What are our great-grandkids going to think about us when they read this as history in 50 years?

    • “What are our great-grandkids going to think about us when they read this as history in 50 years?”

      Hopefully, they’ll learn the lesson that confirmation bias and group think driven by a political narrative is no way to ‘settle’ science for the purpose of justifying demonstrably harmful and otherwise unsupportable policies.

      Unfortunately, we’ve been paying the price for this insanity which won’t change until either the main stream media or the political left supporting the otherwise unsupportable policies learns this lesson. If the MSM catches on first, the political left is doomed, so if those scientists on the left (and you know who you are) want to keep their party relevant, they better accept the scientific method as the only arbiter of what is and what is not science, learn the lesson and gracefully direct their political party away from the insanity.

  3. With regards to the 160 year Battery Park record showing a sea level rise of 11 inches per century, how does one distinguish between sea level rise and land subsidence?

    • The reason why the California Santa Monica coast has mountains 2000 ft tall is that block of land used to be sea floor in San Diego, drifted north and rotated 90 degree clockwise, then uplifted substantially as it slammed into the coast. In Miocene, Bakersfield and much of the Southern CA Coast Range was sea floor. Pretty much everything west of the San Andreas is Miocene sea floor from the Baja border to San Francisco. The Coast Range is a near shore island arc system, historically with the continent to the east at the Sierra Nevada Mtns. The history of Southern California is a history of tectonics and emergence of the land out of the sea. A very tiny interval may show some sea level rise, but the 15 million year history is the opposite. Some fault lurches on the San Andreas cause 10 ft rises in one instant in time. In recent earthquakes, some mountains have risen 3 feet such as in the Sylmar earthquake. I think that was 1969. There are no less than 13 sea level cut benches in the Palos Verdes hills in SW Los Angeles as it emerged from the sea several hundred feet in the Eocene. To say that the long term trend is massive sea level rise or subsidence on the CA coast is just patently absurd. There could be current subsidence from coast groundwater pumping.

      • Right you are Kasper, both here and just below. The west coast of the entire Americas is a mixture of thermal expansion associated with subduction and magmatism/volcanism and transform/transcurrent faulting. The entire western margin of the Americas is in the additive mode due to the subduction episodes. And for sure thermal expansion of the land exceeds thermal expansion of the seawater. However, Ktm’s comment about “the linear march upward captures all the geological phenomena” is interesting and suggests siting issues with tide gauges, which is to say that the place where people live is in delta fill, with compaction issues, and near sea level, not in the middle of nowhere where there are always cliffs against the sea.

    • The linear march upward captures all the geological phenomena. The rapid acceleration since ~1950 due to CO2 is the anthropogenic sea level rise you’re looking for.

      If you can’t see the rapid acceleration since ~1950, try squinting your eyes or going cross eyed and try again.

      • Looking at the entire history, I see all kinds of high frequency spikes in the tide gauge data. But the long term trend is quite clear, and there is no change in the recent data; acceleration or otherwise. If you are seeing “something” in the noise, that’s just wishful thinking. No different than seeing faces or animal shapes in the clouds. No rigorous mathematical analysis will show any meaningful change in the long term trend.

      • Ktm
        “If you can’t see the rapid acceleration since ~1950, try squinting your eyes or going cross eyed and try again.”
        Try
        “If you can’t see the rapid acceleration since ~1950, try squinting your eyes or going cross eyed or putting your hand out for some tax-payers’ dollars, and try again.”
        Fixed it for you. No fee!
        I trust Paul P notes this.

        Auto

        Mods – possibly /sarc, or not, also.
        Maybe a different viewing of the same reality; does that sound homely?

    • Some tide gauges are accompanied by a GPS elevation gauge although the GPS gauges are of course quiet new. Battery Park has a GPS gauge and it has operated only for the last 7 years. It shows a land subsidence of about 2 mm/yr. Thus the actual sea level at Battery Park has been rising at about 1 mm/yr, at least in recent years. The British web site PSMSL.org provides tide gauge records for hundreds, or is it thousands of gauges, I haven’t counted. For some of them, they also show GPS elevation gauges to be found at the “other information” button allowing you to do your own corrections. You can even check Pacific island sites, Miami, and Norfolk Virginia to see whether actual data supports or does not support claims of overwhelming AGW-induced sea level rise. Your findings might surprise you.

      There are other ways to measure long-term sea level changes. In “A Search for Scale in Sea-Level Studies,” Journal of Coastal Research, July, 2006, Larson et al. reviewed available studies of long term sea level rise using data from coastal marshes at various sites and concluded that global sea level has been rising at a rate of about 2 mm/yr or less at least for the past 6,000 years.

      Hope this helps.

    • There is estimated land rise / fall taken from the GPS system. I can’t find a link to it at the moment. Generally if you take in account the GPS data, sea level rise fall between 1.7 to 2.3 mm per year (at least when I ran the numbers). There was talk of launching satellites that would be more accurate in calculating the data, but Congress never funded it.

      BTW: I have read estimates of up to 0.8 mm year of the sea level rise is due to ground water extraction.

  4. Hi Roger,
    I like you live in ChCh – with me being some 33m above sea level.
    Safe at that distance above current sea level, but seeing that video with the 20m rise from the pressure of the tsunami, makes me a little less ‘comfortable’.

    Not however, uncomfortable from the 1.7mm per year rise we get here.

    • Hi DBH,
      Nice to hear from you.

      A while back as you may be aware, the Christchurch City Council tried to put some sort of warning on the title of 1800 properties in our city on the pretext that there were inundation dangers.
      There was a bit of an uproar from these owners and I attended one of their meetings. Unfortunately it was decided there that it was a “legal” issue and this resulted in some withdrawal from the council.
      I got thrown off face book because of my factual arguments saying this was all a result of the belief in a non-existant global warming and the sea level rise had not accelerated yet – etc.

      This is what I put on my blog a little later:-
      https://thedemiseofchristchurch.com/2016/05/06/six-reasons-why-you-should-worry-about-climate-change/?iframe=true&theme_preview=true

      As far as I can tell the council have gone quiet but are p;robably simply biding their time on this one. Have you heard anything?

      Cheers

      Roger
      http://www.thedemiseofchristchurch.com

  5. I love the acronym SEM for semi-empirical model. Definitely semi. it does look like the acronym POOMA better fits their intentions in using SEM sea level rise figures.

    • I read it more like a chocolate bar wrapper. “Warning: May contain trace amounts of facts and/or data”,
      as opposed to the non-empirical model projections that require no such warning.

  6. The new California report is simply authored by those known to be on the public climate gravy train, and in large part is pathetically inaccurate.

    Pretty pictures, however!

    • The California coast for 15 million years is a history of strong coastal emergence from the sea. Everything West of the Pope Valley fault defining the West side of the San Joaquin in Northern CA, for example, is called an offshore island arc system. Snowy Mtn that dominates the area is called a shield volcano that formed offshore. That is how all that volcanics formed. The coast used to be the Sierra Mtns 100 miles east. The entire state San Joaquin Valley used to be called ocean. The entire Coast Range is a recent phenomena that did not exist until plate tectonics formed an offshore volcanic island chain that cut the San Joaquin off from the sea. Converting that into sea level rise is called Stupidville. It represents Pagan earth worship, not geologic science.

    • Thanks Nick

      I’ve only had time to glance through the report. Color me unimpressed. They do have enough sense to recognize that one of their three tidal gauges (Crescent City) is on the upper side of the Cascadia subduction zone and shows no current sea level rise, but will probably be subject to a near instantaneous 1-2 meter downward adjustment — maybe this century. Maybe next. Maybe the century after that. But they still lump all three gauges together. The other two gauges are near active or probably active faults BTW (The San Andreas and the Rose Canyon)

      Anyway, they apparently have developed a “semi-empirical model” which combines actual data with what look like Wild Ass Guesses to paint a picture that is presented as “science”.

      They seem to have missed an opportunity to warn that, based on current notions of geology, Eureka, Crescent City, and some smaller towns on the thinly populated coast between Cape Mendocino and the Oregon border face a very concrete threat of a whopping great earthquake with a substantial sea level change followed by possible tsunami. It’d probably be a good idea to prepare for that eventuality

      Other than that. It is fortunate that most of the California coast is pretty steep. However, in the unlikely event that they are right, downtown San Diego and the huge San Diego Naval Base complex might be in a bit of trouble. along with quite a lot of very expensive beach front property in places to the North.

  7. “… the very significant qualifications, limitations and uncertainties reflected in the report but unaddressed by the climate alarmist media …”

    Which will surely lead many report contributors to very publicly demand apologies, retractions and corrections from the mass media . . ; )

    • It’s kinda ironic, given that the origin of these reports lies with those who have an explicit desire to control what society does both now, and in the future.

  8. The question I like to ask is this….

    “How much lower would sea level be if humans had never walked the earth? Please quantify your answer”

    I generally answer 2 inches. The rate of rise has been remarkably constant in various CO2 forcing regimes. However, I think with groundwater release and thermal expansion and some satellite data acceleration claims, I’m willing to agree to 2″ of human contribution.

    I don’t know how you could support and answer outside the range of 0 to 4″. But, I’m all ears.

    • The consistent rise of the land over the sea in all of Coastal California has been going for for at least 15 million years. Using Bakersfield, CA elevation as a rough estimate, since it used to be under a Miocene ocean, its elevation is now 400 feet above sea level. Before the Ice Age ended, and sea level rose 400 feet, it would otherwise be 800 feet above sea level. Over that time scale, the few mm interval rise between tectonic events would be unmeasurable. Note these models are climate models, not geologic models. So they are using climate to tell us what one of the major crustal plate boundaries in the world are doing as the Pacific and North American plate grind past each other in Central and Southern CA, and the Pacific plate subducts under the NAmerican plate for WA, OR, and Northern CA. Of course the southern section used to be a subduction system, then it switched.

  9. That’s heavy –

    – ’til 4 weeks ‘never ending catastrophic Californian drought’

    – passing: Oroville dam spillway crisis

    – to: meanwhile California sea level rise “model study” claims 10 foot rise by 2100
    ________________________________________

    Outrageous Impertinent journalism:

    Why remember my stupid drivel from yesterday !

  10. Didn’t they tell us all the extra heat hid in the deep ocean during the pause?

    If it did, it certainly didn’t do much thermal expansion down there.

    Alarmists have been staggeringly wrong about catastrophic sea level rise for more than 50 years now. In the Nixon white house archives,
    Daniel Patrick Moynihan cites 10 feet of sea level rise by the year 2000, which came from a 1965 expert report that is available online in pdf form.

    The report is interesting in that they clearly cite 10 feet of sea level rise by the year 2000, then dutifully include typical statements of uncertainty to give themselves deniability. But then they go on to talk about the effects of a meltdown of Greenland and Antarctica leading to another 200 feet of sea level rise over the subsequent 200 years. This projection does not include any hint of uncertainty.

    So by my count, the best alarmist experts of the time, who knew the laboratory greenhouse effect of co2 to very high precision, and had calculated it with computers, missed their prediction by 10 feet by the year 2000, plus another 17 feet at the rate of 1 foot per year over the next 200 years.

    2 – 5 inches? 27 feet? Who’s counting?

      • You can find a link here: http://motls.blogspot.fi/2010/07/nixon-was-told-sea-level-would-rise-by.html

        Key points are
        – There were global cooling and warming alarmists in 1969
        – GHE was explained ‘simply’ as what happens in a greenhouse, which is very very bad comparison
        – The alarmists did predictions that were badly off
        – They added ‘mights’, ‘coulds’, ‘suggests’es’ etc so that you can’t say they were wrong as such, but heroically the first people to warn on the coming apocalypse.
        – Well, they were wrong, of course

      • Google Restoring the Quality of Our Environment 1965.

        I did misremember one detail, they talked about 400 feet of sea level rise over 400 years, not 200 feet over 200 years.

        Their projections of atmospheric CO2 were actually less that what occurred, and as i said they knew the lab CO2 greenhouse effect to extreme precision.

    • I was going to post on the thermal expansion of the oceans. So where is all that heat going if it’s not into the oceans? Thermal expansion is a definite thing. It is not a could or maybe. After at least 20 years, no SLR or very minimal, How does C/AGW explain where the heat is hiding now? Maybe the warmist can explain to me, I’m sure they have, how the heat gets recycled in shorter el nino periods, but without SLR. Do I feel another record adjustment coming up?
      I remember something about that report. It was so fantastical that it was laughable. There were so many of those dooms day prognostications, no one took them seriously.

  11. No one told them

    – we passed 6 years El Niño

    – the new regime is La Niña

    – unpredictable April is followed by

    – May, spell that ‘S P R I N G’ !

  12. Considering the current rate of rise it would probably have to hit 3 or 4 inches per year by 2090 to come close to increasing 10 feet by 2100. The chances of it increasing close to 2 feet by 2050 seem to be incredibly slim. To me a worst case scenario of 3 feet seems much more reasonable. 12 to 15 inches seems much more realistic though or maybe even less.

    The beauty of these predictions is that no one responsible for them will live to see their failure. They can’t lose even when making outlandish claims.

    • Yes, we’ll all be long dead BUT the fallout of the decisions, made now, will still be around

    • To me a worst case scenario of 3 feet seems much more reasonable. 12 to 15 inches seems much more realistic though or maybe even less.

      Going from memory, that’s about what AR5 says in the sea level chapter. You’re probably a bit below them on the probable amount, but not a lot. Don’t have time to look it up right now.

    • Actually really big floods are very unusual in the Donau system, it is one of the least flood-prone of the large rivers of the world. For example Pest, the eastern part of Budapest which is quite low-lying has only been badly flooded once in historical times, in 1856. Though that was a very bad flood, and the reason all the really old buildings are in Buda, which is much higher.

  13. Their it is! The Alarmists special way to incite fear using pseudo science, i.e. “semi empirical,” When I see that my bull shit meter goes ding ding ding!

    • It is a good trick. For years, we have been asking for “empirical evidence” of global warming. So they now come up with “semi-empirical”. And the Kool-Aid drinkers see empirical and think all is well. Presto, chango.

  14. You’d think that these alarmists would put the cart before the horse, and provide evidence of significant global warming before making predictions about its effects.

  15. Ten feet to 2100 requires that virtually the whole West Antarctic Icesheet melts until then (total melt gives sea-level rise of 11 feet). Half of the Greenland Ice-sheet would have the same effect, but is physically impossible in that time-frame since it lies on land and must melt where it is. Interestingly it seems that about half the Greenland icesheet did melt during the Eemian/Sangamonian interglacial. That took 7,000 years at a temperature 8 degrees C higher than today.

  16. Now here is something that will have to be adjusted.

    Sea level change measured by the new Jason3 satellite since Jan 2016. -0.66 mm/year.
    (Jason2 is also showing the same flat or falling trend after the peak of the El Nino in Nov 2015).

    • The sea level always goes down a bit after a Nino. And the Big California Rain may be contributing a tenth of a millimeter or two as well. A lot of that rain/snowmelt will go straight down into the watertable, and it may take quite a while before it gets back to the ocean..

  17. You can’t even get 3′ of sea level rise without rates exceeding the Holocene transgression…

    • I recall a speaker at one of the much watched conferences, showing, like you have Tom, a chart of current day sea level rise, then ‘added’ the projections of a well know alarmist (I forget the doom-sayer name) and the resulting graph line made the ‘hockey stick’ graph, look like a flat liner.
      It was simply ridiculous.
      Would love to re-watch that video, but for the love of me, can’t find it.

      • Ooops, I was actually referring to you, David.

        D’oh!!

        How could I do that to a man I share the same name with??

    • Point taken. There is nothing to see before 2050, and I’m long dead before I could be sued for selling beach front property.

  18. Ten feet by 2100 comes to an average of over ten times the current rate of sea level rise for the next 83 years.

    When is this dramatic run-up going to begin to happen?

  19. In giving guidance on sea level rise one has to ask what is the purpose of producing a H++ scenario (I note that NOAA Technical Report NOS CO-OPS 083 introduced an H+ scenario in Jan this year at 2.5m by 2100, so perhaps they felt the need to go one further).

    These big numbers clearly stake out an upper bound, but how should a decision maker (public or private) use them. The problem is that without any measure of their likelihood they are devoid of information, and it is information that is needed to manage risk.

    Basically this report is telling us that if you take any action it is will cost you more than it will gain in mitigation, simply because we don’t know anything about the risk (however we can paint nasty pictures of the consequences, but that is irrelevant).

    A further note is that these are progressive risks. We’ll have a better idea in 10 years if we do nothing. I can’t think of any management action one might sensibly take given this scenario that is likely to beat the do nothing option.

    We’ll definitely know better in the future. Or maybe not :)

    • Considering the fact that 1 m of additional sea level rise by 2100 is bad science fiction… The “do nothing” option is the second most logical course of action. Only the “adapt to whatever happens” option is more logical.

      • I thought afterwards I should have been clearer. Do nothing that costs you something in response to H++ because it tells you nothing so you will always be throwing money away.

        By all means do something if it will save you money, but you didn’t need H++ to tell you that.

  20. Did I read this correctly? “Many semi-empirical model projections of global mean sea level rise are higher than process-based model projections (up to about twice as large), but there is no consensus in the scientific community about their reliability and there is thus low confidence in their projections”.
    But, but, but, the science is settled, there is a 97% consensus right? /sarc

  21. At least we are ALL in the same boat. (pun TOTALLY deliberate)

    “Now new research from the University of Otago’s Centre for Sustainability has compiled a multi-layered database with superimposed maps.”
    That, as of the 4th April.

    The location of the University, Dunedin, has a significant number of houses only 500mm above current sea level.
    As I recall, the annual rate of rise there is ….drum roll….1.3 to 1.5mm.

    Ummm…excuse me….professor, I have a question……will I have my degree by the time we need to start worrying?

    Oh, my giddy Aunt!!!

  22. ” We note here that the confidence in the ability of SEMs is further reduced with the length of the extrapolation period and the deviation of the future forcing from the forcing of the learning period (Schaeffer et al., 2012), thus decreasing confidence over the long time frames considered here.”
    _________________________________________

    What good is a ‘semi-empirical climate model’ confidenced over long time frames –

    with shorter time frames than min. back to

    1362 – Netherlands, de grote man drout –

    The big ‘men drowning’:

    https://www.google.at/search?client=ms-android-samsung&ei=7pYJWam9BsijwALdpY6wBA&q=++North+sea+de+grote++++manntr%C3%A4nke&oq=++North+sea+de+grote++++manntr%C3%A4nke&gs_l=mobile-gws-serp.

  23. In short:

    will ‘semi-empirical models’ predict life expectancy of EU with Great Britain;

    can ‘semi-empirical models’ predict life expectancy of EU after Brexit.

    Shucks.

  24. Total noob here, but should the sea level be the same all over the globe?

    I don’t understand when I read that the sea rose 11 inches here and 5 inches there….it may be my reading comprehension :)

    • Land also rises and falls so skews sea level measures with tidal gauges. The whole of Scandinavia is a good example where some ancient beaches are some 60m above current sea levels due to isostatic rebound after the last glaciation.

      • It also depends on the prevailing wind, water really does bunch up a bit due to the wind.

    • Drug, I’ll add one more cause for variable sea level: local warming (and cooling) as with El Nino, (or La Nina for cooling) along the equatorial zone, causes expansion (or contraction with cooling) of water volume. The ocean surface is quite “hilly” and the hills appear and disappear, although this ‘topography’ is measured in centimeters.

      • Dang, Drug should read Doug. The word selector in my Samsung is illiterate and a little too politically correct/ social justicey /millennially cultural for my liking.

    • “should the sea level be the same all over the globe?”

      You’d think so, but it turns out that it varies quite a lot depending on latitude, depth and density of underlying rocks, prevailing winds, river outflows etc, etc, etc. The differences aren’t huge — a few tens of meters as I recall. But when you’re looking at changes on the order of one or two thousandths of a meter per year, the oceans look pretty bumpy.

    • The height of the sea depends on how warm water there is, so heated layers somewhere mean higher sea level there. Salty water means lower sea level. Glacial melt during the last 10,000 years means the rock is moving up at some places and down elsewhere. All these and other reasons mean it is not very sensible to talk about the global mean seal level only. What matters is whether your mat wets or not. My mat is not wet.

      There are lots of places with subsidence. But then, there are many places where sea recedes and will recede unless we somehow end up with RCP8.5 like scenario – which is pretty much impossible. The cagw is built on a Drake formula – an expression with many unknowns, all rounded up, multiplying the error up.

      Curry has a good term on purposeful production of round-up-errors: advocacy sciense. You can round up amount of people, amount of energy they use, amount of C available, speed of C burning, loss/growth of sinks, CO2 sensitivity, glacier melt, ocean heat content, and subsidence. By combining these (on purpose or by sheer lack of sense) one can arrive at outlandish might-predictions like Daniel Patrick Moynihan did in 1969.

      There is no point in talking sense now. Wait 20 years more so all the old alarmists have retired, then there can be a change.

    • GMSL is ,like many things in climate “science”, calculated as an anomaly of the difference of the the reference ellipsoid and the geoid, both concepts which, if not completely arbitrary are nevertheless completely artificial.

      “The geoid is the shape that the surface of the oceans would take under the influence of Earth’s gravity and rotation alone, in the absence of other influences such as winds and tides. This surface is extended through the continents (such as with very narrow hypothetical canals). All points on a geoid surface have the same gravitational potential energy (the sum of gravitational potential energy and centrifugal potential energy). The geoid can be defined at any value of gravitational potential such as within the Earth’s crust or far out in space, not just at sea level. The force of gravity acts everywhere perpendicular to the geoid, meaning that plumb lines point perpendicular and water levels parallel to the geoid if only gravity and rotational acceleration were at work.

      Specifically, the geoid is the equipotential surface that would coincide with the mean ocean surface of Earth if the oceans and atmosphere were in equilibrium, at rest relative to the rotating Earth,[1] and extended through the continents (such as with very narrow canals). According to Gauss, who first described it, it is the “mathematical figure of Earth”, a smooth but highly irregular surface whose shape results from the uneven distribution of mass within and on the surface of Earth. It does not correspond to the actual surface of Earth’s crust, but to a surface which can only be known through extensive gravitational measurements and calculations. Despite being an important concept for almost two hundred years in the history of geodesy and geophysics, it has only been defined to high precision since advances in satellite geodesy in the late 20th century. It is often described as the true physical figure of the Earth,[1] in contrast to the idealized geometrical figure of a reference ellipsoid.”

      You will note that the range of values for geoid height vary over a range of over 180 meters which means the supposedly “level” seas actually differ in “absolute” terms by similar amounts.

      Until the advent of the GRACE sats the altimetry of sea level was all calculated from a constant version of the geoid model to try to maintain consistency throughout the data, and because the Earth,s gravitational field was supposed to be relatively stable. After GRACE demonstrated that that stability was questionable adjustments were attempted, but personally, I wouldn’t bee betting the farm on the consistency of the GMSL altimetry database.

    • And to complicat things further a melting icecap has very different effect in different places. Near the icecap the sea-level goes down when the icecap melts because the decreased self-gravitation effect is larger than the sea-level rise. The increased gravitation from a large icecap draws up the sea-level nearby just like a mountain does.

  25. There is a “doth protesteth too much” aspect to these long-winded analyses, especially with century plus uneventful straight line gauge data. Larry you are too kind in describing the stuff as conjecture and speculation. It’s much less innocent than that.

    There are conditions equally as likely in the future that are not considered here at all that could give rise to a H- – scenario if you want to make the projection a scientific one. It is a huge, unwarranted assumption that the future is going to be a warmer one. So what is the median for 2100, essentially an extension of the tide gauges data is the best we can do. The upper bound, since the models have demonstrated a 300% overly warm projection over a third of a century would make the worst case scenario ~ +1m with low confidence.

  26. Since temps aren’t following their CAGW script, they have to pound the “effects” of warming, like SLR, glaciers calving melting, and “extreme” weather. In WarmLand, it’s always “worse than we thought”, and we “have to act now, before it’s too late!”

  27. While we’re on the topic of sea level, Colorado University’s Sea Level Group
    http://sealevel.colorado.edu/
    is way overdue to come out with the first release for 2017.
    Last year their first release for 2016
    https://web.archive.org/web/20160128005123im_/http://sealevel.colorado.edu/files/2015_rel4/sl_ns_global.png
    dropped the note that they were correcting for GIA, and no one on the skeptical side of things even blinked. There’s only one mention of GIA on the main page, listed under FAQs. Will that be gone on the next release?
    They had been running this title
    NASA Satellites Detect Pothole on Road to Higher Seas
    for some time, obviously complaining that we aren’t getting to catastrophic levels of sea level fast enough.
    The current release
    http://sealevel.colorado.edu/files/2016_rel4/sl_ns_global.png
    dates from last September and doesn’t yet include data from the Jason-3 satellite, but they ran this title:
    Is the detection of accelerated sea level rise imminent?
    Looks like a prediction of things to come.
    Several years ago a link to this slide show presentation
    Why has an acceleration of sea level rise not been observed during the altimeter era?
    could be found on one of thier pages
    And a more recent slide show
    Challenges for Detecting an Acceleration of Sea Level Rise in the 23-Year Satellite Altimeter Record
    does in fact show acceleration of 0.0133 mm/yr² (mm/yr/yr) But clearly they want find more.
    Sure looks like they’re going to find acceleration no matter what.
    So, it’s probably a good bet that when the 2017 Release #1 finally comes out they will find their long desired acceleration of sea level rise, and it’s probably another good bet that something much greater than 0.0133 mm/yr² will be trumpeted – most likely a result of data adjustment more than anything else.

  28. No one has so far mentioned the impact to sea level rise from aquifer depletion. I’ve seen estimates that range from .5 mm/yr to 1.5 mm/yr. More electrification, more horsepower, more depletion, more sea level rise. But none of it is due to CAGW.

    When the issue of sea level rise first began, alarmists would point to areas where either the coast was subsiding (Louisiana) or sliding into the ocean (California). They don’t do that anymore as it became obvious how dishonest they were. Now they take a satellite with a resolution in cm’s and translate that to rise in mm’s. Then they tell us that the ocean floor is sinking to that they need to adjust for that movement. But even the horrendous sea level chart put out by CU doesn’t show acceleration in rise.

    If you can still see the ocean level marker at the Isle of the Dead at Port Arthur in Tasmania, it means theres nothing to see here, just another example of hype by the ignorant and dishonest press.

    • To be fair, as a counter to aquifer depletion you also have to factor in the creation of dams, which result in less water going into the oceans.

      • Yes and No, Mark. Mostly, dams simply slow down the rate of flow. Most of the flow still goes to the end point as it did before dams with two minor exceptions. First, there is increased evaporation from a larger surface reservoir but that in the end gets rained back down to the ground somewhere else and makes the local climate more moist (Makes for good spring skiing with nice overnight spring powder in the area of the impoundment.) Secondly, the reservoir increases the amount of ground water around the reservoir as the higher water level results in infiltration of water into the ground around the reservoir – BUT – DECREASES the amount of water that would have gone into the ground downstream during the spring freshette. Elementary reservoir routing was part of first or second year engineering and higher level soil mechanics and more detailed routing in later years if you were taking water resources courses as I did. Figuring out if a particular dam results in less water going to the ocean is actually a pretty complex issue, although generally speaking, reservoirs just smooth out the flow and the water all goes where it would have anyway – into the ocean, the air, or the ground.

      • Once full, the amount of water entering a reservoir equals the amount leaving. However this isn’t true while the reservoir is filling. That is water that is being held back from flowing to the oceans.

  29. How about subsidence of the land due to the pumping of the coastal ground water. Who is monitoring those statistics and its potential contribution to costal flooding??

  30. California tumbles into the sea
    That’ll be the day I go back to Annandale
    Tried to warn you about Chino and Daddy Gee
    But I can’t seem to get to you through the U.S. Mail


    @ 3:28
    “My Old School.” by Becker, W. & Fagen, D.
    From the album: Countdown to Ecstasy by Steely Dan (1973)

  31. NOAA ?!?! Who needs NOAA when we have Nat Geo Magazine?

    Nat Geo, May 2017, p. 158:

    ‘If climate change makes the sea level here rise 22 to 30 inches by 2100, as scientists predict . . . .’

    The world of science is broken.

    • You’re right Ferd. BUT, tidal gauges are remarkably unevenly distributed — largely only in advanced countries in places that are centers of commerce. And an awful lot of them are in places that are known to be tectonically active — which means that until we have a number of decades of GPS data to confirm their rates of uplift or subsidence, we can’t correct the measurements properly. Check back in 2035 or so and you’ll get a better picture.

      On paper, satellites are probably better because they can measure sea level anywhere there is (ice free) sea. And they laugh at tectonics. But they have their own problems.

      • Much depends on the individual ads you see. I had this problem for some time, but then it has been replaced with extra slow load times.

    • As soon as the page loads, click on [ X ] (stop loading this page) upper left – at least that’s where it is on Chrome.

      • The stop loading function does not work well. Usually the page is not yet loaded and sections are missing, or the X does nothing, or the page reloads in any case after pressing the X. There is a number of nice effects you can do with scripts that are malicious.

      • You need an ad blocker, Hugs. It will click that “x” for you.

        My adblocker, Noscript, currently shows ten different websites wanting to load their content onto this page, but thanks to the adblocker, none of that stuff is loaded in the first place, so you get no ads and the page loads like it should.

    • This problem of the page suddenly jumping back to the end of the article started today with my MS Edge browser. It wasn’t formerly an issue. It would seem therefore to be a problem with WordPress.

  32. California needs to worry about earthquakes. But it is kind of hard to generate tax revenue from earthquake fear mongering. Climate change is definitely a much easier rout to taxation.

  33. What an odd usage, “Semi empirical” when they really mean totally fictional.

    There may be some observations beginning their research, but all SLR movement is fictional, not observed.

    I presume the ‘Rahmstorf’ writing fictional SLR stories is the same Rahmstorf pretending to unsubscribe from the NYT?

    “falsis in unum, falsis in omnibus”
    False in one, False in all!

    • Computer modeling is supposed to “model” the real world’s climate systems with computer software, as a poor-man’s substitute for actual data, when actual data is unavailable. But “semi-empirical modeling” doesn’t even try.

      “Semi-empirical modeling” is an oxymoron: “modeling” that doesn’t model anything. It is sort of like modeling, but without reference to any physical basis. It can be made to produce just about any result you want.

      GCMs are subject to criticisms that they don’t accurately model the real world, because of inconsistency with observations of things like clouds and the predicted tropical mid-tropospheric hot spot. The semi-empirical modelers neatly avoid such criticism, by not even trying to model the real world.

  34. I noted in reading the quotes that the predictive MSL models are based on predicted global average temperatures. They should be using the predicted average temperatures of sea water in the upper mixed layer instead of conflating SSTs with air temperatures over land. Water temperatures increase more slowly than land temperatures or the average!

    Those who are responsible for making tide tables are well aware of numerous cycles that control the tides, some with periods of around 20 years. I never see mention of taking the constructive/destructive interference of these cycles into account when making forecasts.

    It looks to me like the New York MSL, which doesn’t experience the El Nino effects, has actually declined since about 2010. I realize that this may be due in part to isostatic rebound, but prior to about 2010 that was being overridden by rising water.

    Once again, alarmists only present part of the picture, apparently cherry picking the things that best agree with their bias. It might be ignorance on their part. After all, one wouldn’t expect mathematicians and astrophysicists to be familiar with a lot of Earth Science details. However, when it happens with such regularity and even from ‘climate scientists’ of all stripes, one is left with the impression that it is deliberate obfuscation.

  35. Would it help to illustrate the absurdity of a 10 foot rise in sea level over 70 years to extend the graph and pop a trend line with a slope that the sea level would have to take to achieve this absurd prediction?

  36. Could someone explain the “Apparent Data Shift” for Freeport, TX of about 0.2meter (up) around 1970? (https://tidesandcurrents.noaa.gov/sltrends/sltrends_station.shtml?stnid=8772440 ). I am looking at at a graph showing comparisons of tides for March 1937-March 1938 for Rockport, Port Aransas and Corpus Christi. There is no Port Aransas shown, 1930s data shows up for Rockport, but not for Corpus Christi. It looks like no Texas Gulf measurements from Galveston almost to the Rio Grande.

    There were water level effects on the upper Texas/western Louisiana coast in March 1964 from the Alaska earthquake. Not aware of earthquake activity in that part of the world, but lots of subsidence some faults maybe.

    This may be posted twice–something shaking my machine.

    • H. D. Hoese, there’s very little measurement data for Port Aransas:
      http://www.sealevel.info/MSL_graph.php?id=922

      Corpus Christi has data only since the mid-1980s:
      http://www.sealevel.info/MSL_graph.php?id=Corpus+Christi

      Rockport is a lot better, though the data before 1963 is very sporadic:
      http://www.sealevel.info/MSL_graph.php?id=Rockport

      Galveston, of course, is a very good quality, long, measurement record, except that it is distorted by ongoing compaction of the fill dirt from when the city was raised a century ago:
      http://www.sealevel.info/MSL_graph.php?id=8771450

      And here’s Freeport:
      http://www.sealevel.info/MSL_graph.php?id=Freeport

      I don’t know much about the “apparent datum shift” for Freeport, except that NOAA dated it 1/1/1972. But I can guess where it comes from.

      I suspect that they first noticed the apparent 1971 jump in sea-level at Freeport, and decided to take a closer look. They would have compared it with the two adjacent gauges, one in each direction. As you can see in this map (from PSMSL’s page), that would be Galveston to the NE, and Rockport to the SW:

      They presumably noticed that a 1971-75 sea-level spike was also visible at the two adjacent gauges, but that it was transient at those gauges, unlike Freeport, where at least half of the “spike” seems to have persisted. That looks suspiciously like there might have been a problem with the Freeport gauge, perhaps with how it was referenced to the local geological benchmarks. Maybe.

      You can’t really see what I’m talking about in the full graphs, so let’s use the sealevel.info “Options” to zoom in. Here’s just the 1960s & 1970s for Freeport (in black):
      http://www.sealevel.info/MSL_graph.php?id=Freeport&g_date=1960/1-1974/12&s_date=1960/1-1979/12&linear=0&lin_ci=0&co2=0&thick&colors=2

      Here’s the same period for Galveston (in blue):
      http://www.sealevel.info/MSL_graph.php?id=8771450&g_date=1960/1-1979/12&s_date=1960/1-1979/12&linear=0&lin_ci=0&co2=0

      Here’s the same period for Rockport (in blue):
      http://www.sealevel.info/MSL_graph.php?id=Rockport&g_date=1960/1-1979/12&s_date=1960/1-1979/12&linear=0&lin_ci=0&co2=0

      Here are the three graphs merged. (Sealevel.info won’t do this — I used Irfanview, Paint.net, Irfanview again, and then MSPaint). As you can see, there does seem to be a step-change around 1/1971-72 at Freeport, which is not visible at Galveston and Rockport:

      Or you can pull up the three graphs in three browser windows and toggle back and forth between them, and you can see the same thing.

      I’ve found nothing about a possible cause for the issue. PSMSL has only a few notes on the Freeport gauge, and nothing about that issue:

      =========================== FOLLOWING PSMSL DOCUMENTATION ADDED 29-JUL-93 :
      Many stations on the Gulf coast have large values for September 1961.
      =========================== FOLLOWING PSMSL DOCUMENTATION ADDED 11-JUN-91 :
      Freeport 940/006 RLR(1973) is 11.1m below BMR455
      =========================== FOLLOWING PSMSL DOCUMENTATION ADDED 14-JUL-94 :
      For a discussion of submergence near to Galveston, Freeport and Sabine Pass, see Emery and Aubrey (Sea Levels, Land Levels and Tide Gauges), 1991, Springer-Verlag, page 39.
      =========================== FOLLOWING PSMSL DOCUMENTATION ADDED 23-Feb-2015 :
      NOAA website confirms this station was removed in March 2008
      
    • Datum-level shifts are not uncommon in coastal sea-level time-series. They are usually the result of local geological shifts. In the case of Freeport, I would look toward the extensive oil extraction by “Texas towers” that mushroomed in that region during the ’60’s and ’70’s for potential explanation.

  37. See also:

    Coastal planning should be based on proven sea level data, by Parker and Ollier
    http://www.sciencedirect.com/science/article/pii/S0964569116300205
    Highlights
    The network of tide gauges provides the only information of value for costal planning.
    The worldwide naïve average of sea level is +0.24 mm/year with no acceleration.
    The climate models have crucial flaws making them useless.
    Planning schemes must only reflect the proven local and global historical data.

    • talldave2

      The Parker and Ollier quote suggest that, perhaps, the science is not yet fully settled. Thanks!

      If so, the VouDou Idol of CAGW may be built upon shifting sands.

      Auto

  38. California seems to be in a “bidding war” to see who can come up with the most wildly unscientific sea-level projections.

    Reality: Six inches. Ten inches in some places, with high subsidence.
    Florida wackos: I bid six feet!
    New Jersey wackos: Nine! I bid nine feet!
    California wackos: Ten! I bid ten!

    In the real world, the most important thing to know about sea-level rise is that sea-level rise is not accelerating in response to climate change. Two-thirds century of heavy CO2 emissions, and the attendant global warming, have not caused the rate of sea-level rise to increase at all.

    All the high-quality, long-term (~100 year or more) sea-level measurement records show that fact. They are all very close to linear since at least the 1920s, most for even longer than that.

    Some locations saw a slight accelerations in rate of sea-level rise sometime in the late 1800s or early 1900s, but none have measured any significant, sustained sea-level rise acceleration since then.

    All the acceleration in rate of sea-level rise occurred when CO2 was under 310 ppmv. When CO2 rose above 310 ppmv, sea-level rise acceleration ceased.

    Over eight decades have elapsed since then. Still there’s been no detectable acceleration in sea-level rise. Sea-level is still rising at a glacially slow globally averaged rate of only about 1½ mm/yr (6 inches per century).

    Here are some representative graphs, showing sea-level (in blue) juxtaposed with CO2 (in green):

    Atlantic:
    http://www.sealevel.info/MSL_graph.php?id=Harlingen&boxcar=1&boxwidth=3

    North Pacific:
    http://www.sealevel.info/MSL_graph.php?id=Honolulu

    South Pacific:
    http://www.sealevel.info/MSL_graph.php?id=Sydney

    To anyone with a STEM education, it should be obvious from those graphs that CO2 level is not significantly affecting the rate of sea-level rise.

    To anyone reading this for whom that isn’t obvious, here’s a page which should help:

    http://www.sealevel.info/acceleration_primer.html

    Even President Obama’s former Undersecretary for Science, Steven Koonin, has noticed that:

    “Even though the human influence on climate was much smaller in the past, the models do not account for the fact that the rate of global sea-level rise 70 years ago was as large as what we observe today.”

    This fact is as clearly proven as anything in climate science, yet the climate campaigners steadfastly refuse to accept it. Most of them seem to think it is impossible. I guess they think that when all the data conflicts with their theory, all the data must be wrong.

    It amazes me that so many climate scientists seem to be unaware of the fact that global warming has effects which decrease, as well as increase, sea-level. They always mention melting and thermal expansion, which raise sea-level, but they never mention how warming increases snow & ice accumulation on glaciers and ice sheets, reducing sea-level.

    It does so by decreasing seasonal sea ice coverage of the Arctic and Southern Oceans. Decreased sea ice increases water evaporation from the sea. The additional evaporation increases “lake-effect/ocean-effect” snowfall downwind. Some of that snow falls on the ice sheets and glaciers, increasing ice accumulation, and offsetting meltwater losses.

    That’s important, because snow accumulation has a huge effect on grounded ice mass, which in turn affects sea-level.

    The magnitude of ice accretion from snowfall on ice sheets was illustrated by the team which salvaged a WWII P-38 (now called Glacier Girl) from under 268 feet(!!) of accumulated ice and snow (mostly ice), 50 years after she landed on the Greenland ice sheet. That is an astonishing number, more than 5 feet of ice per year, which is equivalent to more than seventy feet of annual snowfall. That snow represents evaporated water, mostly removed from the Arctic Ocean.

    The fact that the global warming since the 1920s has caused no acceleration in sea-level rise strongly suggests that the offsetting, opposite-sign effects of global warming on sea-level are similar in magnitude. That means there’s no reason to expect that to change, either. Predictions of wildly accelerated sea-level rise are based on computer models rather than physical evidence, and the assumptions in those models are based on superstition rather than science.

    We’ve done the experiment, and we’ve seen the result. 2/3 century of heavy carbon emissions raised CO2 levels by 95 ppmv (30%), and CH4 levels by 0.68 ppmv (60%), but there’s been no detectable effect on sea-level.

    • The glacier girl is a nice talking point, but it is a red herring if you try to talk about the mass balance.

      OK, I must admit I’m not worried about the Greeland glacier mass balance, it looks pretty stable for hundreds of years under severe warming.

      But your point about sea level, that is interesting. I’m claiming satellite-measured sea level has no meaning what so ever. The only thing that matters is the coastal level measured with a gauge, and that has not been accelerating at any level that would be a real talking point. All this scare is still about future, even when we have 410 ppm CO2.

    • Before I found all the resources talking about climate change / CO2 etc, the one piece of ‘logic’ which bugged the hell out of me was within your comment daveburton.

      “but they never mention how warming increases snow & ice accumulation on glaciers and ice sheets, reducing sea-level.”

      How can it be, that such a simply and understandable piece of the needlessly complicated issue, is there for all to consider?
      It can’t be dismissed, yet seems grossly under-played in any reasonable discussion…. that of the counter balance arguments.

      • D B H
        Sorry.
        ‘counter balance arguments’ – now, wash your mouth out!

        The True, Revealed and Believed-by-the Gullible watermelon mantra of CAGW does not permit ‘counter balance arguments’ – obviously – since it is the only real religion/belief-system/world-power-annexation-technique out there.
        And their ideal population is around 500-750 million. Half India or China, not much more than the European Union (as unified by German ‘leadership’, I gather).
        The rest of use must just die.

        Now, to please the marxians and control freaks, EUists, and others, had you not better put yourself into a wicker man [along with me, for sure, and perhaps others ‘of this parish’] and immolate us all?

        Auto
        Mods – /SARC-SARC Cubed++ [with knobs on].

        Just in case anyone doubted this at all – even for a femto-second . . . .

    • Correction:
      New Jersey wackos: Nine! I bid nine feet!
      should be:
      Rhode Island wackos: Nine! I bid nine feet!

      The New Jersey wackos are projecting up to twelve (12) feet.

      Don’t anybody tell the California wackos, or they’ll surely bid 13.
      .

      I agree, Hugs, that the satellite altimetry sea-level data is useless for coastal sea-level projections. Satellite altimetry does not & cannot measure coastal sea-level. It is a different quantity, measured by radically different (and much less reliable) means; in entirely different places. It is not directly comparable with coastal sea-level, and should not be conflated with it.
      .

      DBH, it is so bad that I’ve seen peer-reviewed, published literature, in a prominent climate journal, which declares that “the laws of physics” require that warmer temperatures must cause accelerated sea-level rise, because of increased ice melt and thermal expansion, with nary a mention of snow deposition on glaciers and ice sheets. I am convinced that the authors were (and perhaps still are) completely unaware of the existence of lake/ocean-effect snow. That such rot could get through peer-review is, IMO, a severe indictment of climate science’s peer-review system.

    • “The fact that the global warming since the 1920s has caused no acceleration in sea-level rise strongly suggests that the offsetting, opposite-sign effects of global warming on sea-level are similar in magnitude.”

      You assume fixed basin.

      • Gamecock wrote, “You assume fixed basin.”

        No, not fixed, just linear (or very nearly so).

        Peltier calculates/estimates that post-glacial sinking and broadening of the ocean basins causes the equivalent of 0.3 mm/year of sea-level decline, per year. I have no idea how accurate that is, but it doesn’t matter for this purpose. All that matters is that, on a century-level timescale or shorter, it’s definitely very close to linear. I.e., if it is 0.3 mm/yr now, then it was also about 0.3 mm/yr a century ago, and it will also be about 0.3 mm/yr a century hence. Or, if it is 0.5 mm/yr now, it was also about 0.5 mm/yr a century ago, and it will also be about 0.5 mm/yr a century hence. Or, if it is 0.1 mm/yr now, it was also about 0.1 mm/yr a century ago, and it will also be about 0.1 mm/yr a century hence. In other words, regardless of the exact value, the rate, so long after the last major deglaciation, is by now certainly very close to linear.

        That means it cannot significantly add to or subtract from measured (zero) sea-level rise acceleration over the last eight decades..

      • “I have no idea how accurate that is”

        It is little more than a guess. Peltier’s GIA models fit very badly to actual measurements, particularly in Antarctica. Even the latest one (ICE-6G) is markedly inferior to other models in this area, though it is better than ICE-5G which had an absolutely terrible fit:

      • Thank you, tty.

        Even if their regional GIA numbers are often way off, their 0.3 mm/yr estimate of the effect of post-glacial sinking of the ocean floor might still be right.

        Coincidentally, I corresponded with Dr. Peltier’s associate about the relative merits of their various models & datasets, only a week ago. Drop me an email and I’ll forward the conversation to you.

        One of the questions I asked them was which of their GIA models they think works best. This is part of the reply I received.

        “Since I must hope that the model is improving with time, I would use ICE-6G_C (VM5a)
        However, although VM5a gives much improved results in North America, it does not do as well as VM2_L90 in Britain for example. But I would counsel against using any results from before March 2012 [due to a bug which was corrected then]…”

        Whose GIA models & numbers do you think are at least as good as Peltier’s? (Links would be greatly appreciated!)

      • daveburton:

        Here is an excellent review and comparison of existing GIA models with particular reference to Antarctica (it is open access):

        http://onlinelibrary.wiley.com/doi/10.1002/2016JB013154/full

        As you can see RATES is well ahead of other models when compared to actual data while ICE-6G deviates badly. I think this has historical reasons. ICE-5G was based on earlier theories that the Antarctic icecap was much larger during the LGM, and responsible for MWP-1A, which would entail a large GIA correction. However continued glaciological research has shown that the Antarctic icecap mostly only expanded sideways a bit as a result of lower sea-levels due to NH ice. ICE-6G corrects this for East Antarctica but still postulates a large expansion of the WAIS. However further studies of residual moraines and exposure dating in West Antarctica indicates that glacial expansion was quite modest there too and that MWP-1A was definitely NH-sourced, while at the LGM the EAIS may even have been thinner than now.

        Of course GIA-correction modelling is really only needed in Antarctica and to some extent in central Greenland and for the sea-bottom around Greenland. Otherwise the isostatic movements in the northern hemisphere.are quite well known from actual measurements.

        Another interesting point is made in figure A1 in the paper which shows two mass-change estimates based on GRACE. Now GRACE measurements are extremely accurate and the sources of errors are very well understood, but even so small differences in the processing of the raw data results in considerable discrepancies in e. g. Wilkes Land.

      • “The fact that the global warming since the 1920s has caused no acceleration in sea-level rise strongly suggests that the offsetting, opposite-sign effects of global warming on sea-level are similar in magnitude.”

        Without knowledge of the size of the basin, and it’s variability, we know nothing.

      • Gamecock wrote, “Without knowledge of the size of the basin, and it’s variability, we know nothing.”

        Not so. The question is about sea-level rise acceleration. To know whether basin size has affected that, we do not need to know the size of the ocean basins, or how fast they are changing, we only need to know that any such changes are approximately linear.

        That really isn’t in doubt. 7,000 years after the last major deglaciation, PGR has been tapering off for a long time, and that long tail is certainly close to linear, on century-level timescales.

        Plus, to the extent that the rate of PGR is changing, it is declining. If that decline were large enough to be noticeable, it would cause an acceleration in sea-level rise, but no such acceleration is in evidence.

        So, to take a concrete example, it might be that 100 years ago PGR was accounting for 0.31 mm/year of sea-level decline, and now it is only 0.29 mm/year. If that is the case, then it would mean that, if nothing else changed, there would be 0.02 mm/yr/century (0.0002 mm/yr²) acceleration evident in the sea-level record.

        The fact that no detectable acceleration is evident in the sea-level record over the last eight decades indicates that either the acceleration from decreasing PGR is too insignificant to be noticeable, or that it is offset by deceleration in factors which contribute to sea-level rise, such as meltwater.

        In other words, the uncertainty in basin changes does not weaken the evidence that CO2 and global warming are not significantly driving sea-level.

  39. Am I wrong here? Ok, the claim is that sea level is likely to rise due to melting ice. Isn’t the coast likely to see earthquakes and perhaps tsunami’s sometime in the not too distant future. I’m assuming that these events will cause little damage since we must instead be more worried about the sea level rise, right? It seems to me the folks on the coast might want to leave now since disaster is coming regardless!

    • “sea level is likely to rise due to melting ice”

      Sea level is likely to continue to rise at the same speed it has done for the 20th century. It might speed up a little bit, but some scenarios by very famous scientists are quite far-fetched.

      There is absolutely no reason to panic. Measuring sea level to a millimeter is theoretic. Ever heard of waves?

    • There are miles of rock on top of most fault lines. Adding a few millimeters of water to that won’t matter.

      • Actually most fault lines go all the way to the surface. And, yes, increased water loading might set off earthquakes a little earlier than they would have happened otherwise. The effect is well documented for dams in seismically active areas. Of course in those cases it was a matter of tens to hundreds of meter of water.

  40. Historical sea level rise can be checked by photos.
    Historical photos of Liberty Island and Brooklyn Bridge in New York harbor show very little sea level change since the 1880s. Compare photos taken in 1880s to current day and very little change is seen, certainly not 11 inches.
    Need to look at more than one photo due to changing tide levels.
    Note that typical New York harbor tide ranges at least several feet daily, with tide ranges of 5 feet common over longer periods. I doubt that any local expert on New York tides would claim that there is any significant long time period changes due to mean sea level.

    • The longest NYC tide gauge is at The Battery, in Battery Park. Subsidence there seems to be higher than is typical in the region.

      The subsidence at Battery Park is most likely due to a combination of several factors: natural compression of reclaimed/landfill land, subsidence of Manhattan in general because they built a lot of tall, heavy buildings on it, and post-glacial isostatic rebound — none of which have anything to do with anthropogenic global warming or CO2.

  41. Some levees I used to ride my bike on as a kid (40 years ago) on SF Bay show no noticeable change in the various bands of pickleweed, cord grass, mud. Said levees have not been increased. Doing the math, there would need to be a major inflection for there to be even one foot of rise by the end of the century let alone a yard or even more far fetched 10 feet.

    • And I live on the Baltic where the land is still rising faster than the sea. I can walk in ordinary shoes on salt marshes that took gumboots when I was a kid.

      But the sealevel hysteria in Sweden is if anything even worse than in California, while at the same time they arfe lowering the quays in Stockholm because they are now too high…..

  42. My thanks to Larry for an excellent article. I’ve added one graphic as an update to the head post, showing just what these charming folks are claiming will happen by 2100 …

    Best to all,

    w.

  43. Thanks Willis – well done indeed.

    Great graphic – “one picture is worth a thousand words” comes to mind.

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