Latest Data Show NO SEA LEVEL RISE ACCELERATION Since 1993…Coasts: Less Than 2 Millimeters Rise Annually!

Satellite Data Show No Acceleration In Sea Level Rise Over Past 25 Years

Image: NASA Earth Observatory  (public domain)

Dr. Sebastian Lüning and Prof. Fritz Vahrenholt today here are asking how sea level rise is doing because as have not heard much about it lately. A good place to start is at Climate4You. Strangely the data go only until December 2016. And if you look at the data from the source form the University of Colorado, we find the same. So what’s with 2017?

The Silence of the Sea Level Rise

Today we know that satellite data must undergo a number of steps before a sea level rise figure can be reached. In April 2017 a study appeared in the Geophysical Research Letters, where corrections were made. As a result the average sea level rise since 1993 was not 3.3 mm/year, but rather 3.0 mm per year. This was hardly music to the hears of alarmists.

And what was really peculiar was the headline appearing in Nature concerning the study:

Satellite snafu masked true sea-level rise for decades
Revised tallies confirm that the rate of sea-level rise is accelerating as the Earth warms and ice sheets thaw.”

Here Nature unabashedly covered up the lower sea level rise. Also all the natural variability of ocean cycles was ignored. The reality is that there is no sign of an increased rate, as Willis Eschenbach at WUWT calculated. That’s been confirmed by a NASA study appearing in November 2017 in the Journal of Geophysical Research (Beckley et al. 2017):

On the “Cal-Mode” Correction to TOPEX Satellite Altimetry and Its Effect on the Global Mean Sea Level Time Series
Comparison of satellite altimetry against a high-quality network of tide gauges suggests that sea-surface heights from the TOPEX altimeter may be biased by ±5 mm, in an approximate piecewise linear, or U-shaped, drift. This has been previously reported in at least two other studies. The bias is probably caused by use of an internal calibration-mode range correction, included in the TOPEX “net instrument” correction, which is suspect owing to changes in the altimeter’s point target response. Removal of this correction appears to mitigate most of the drift problem. In addition, a new time series based on retracking the TOPEX waveforms, again without the calibration-mode correction, also reduces the drift aside for a clear problem during the first 2 years. With revision, the TOPEX measurements, combined with successor Jason altimeter measurements, show global mean sea level rising fairly steadily throughout most of 24 year time period, with rates around 3 mm/yr, although higher over the last few years.

As is the case with the global warming hiatus, there is now scrambling going on for ideas to explain the lack of sea level rise.

A press release issued by the  National Science Foundation is floating the idea that volcanoes could be a reason. The idea ocean cycles might be playing a role obviously has not occurred to the NSF scientists.

Trust “taking a hit”

Vahrenholt and Lüning also write that with all the steps the satellite sea level data have to go through, it is “little wonder that trust in satellite measurements is taking a hit”. Mörner (2017) suggests putting less emphasis on satellite-based measurements and putting it more on coastal tide gauges (where people actually live). Tide gauges globally show a sea level rise rate of only 1.5-2 mm/year.

Also the future does not look anywhere near as bad as it is often portrayed. One reason is that scientists are anticipating increased snowfall over Antarctica, which stores huge amounts of water at the South Pole.

A few years ago Judith Curry stopped doing research and now consults companies and authorities on the subject of climate change. A number of clients have shown up at her door and asked her to submit a serious analysis of sea level rise over the recent decades and provide an estimate of what to expect in the future.

In a separate Part 2, Curry summarizes her findings:

The geological record for sea level rise provides important context for recent sea level rise. However, the uncertainties in the geological sea level  record are substantial, associated with sparse sampling, uncertainties in the proxy methods and uncertainties in the analysis methods. Is the 20th century sea level rise unusual? Sea level was apparently higher at the time of the Holocene Climate Optimum (~ 5 ka), at least in some regions. I have not seen an overall assessment of this, but there have recently been numerous publications providing local evidence for higher sea levels during this period. Whether or not sea level was higher during the Medieval Warm Period than current levels remains uncertain, and there is substantial disagreement among different reconstructions on the sea level during the MWP, with the Grinsted et al finding substantially higher sea level values during the MWP (around 1150 AD). Kopp et al. find the 20th century rate of sea level rise to be the highest in the last 27 centuries. However, since their data is barely resolved at 100 year time scales (with decimeter vertical resolution), I would not place  high confidence in their conclusion. Eyeball examination of Grinsted et al.’s Figure 7 shows possibly higher rate of sea level rise between ~1000 and 1100 AD. Overall, I find Kopp et al.’s analysis to be more convincing (apart from overconfidence in the relative rate of 20th century sea level rise). The pace of interesting and important paleo sea level rise research seems to have accelerated since publication of the AR5, I will be following this closely.”

25 responses to “Latest Data Show NO SEA LEVEL RISE ACCELERATION Since 1993…Coasts: Less Than 2 Millimeters Rise Annually!”

  1. Kurt in Switzerland

    Not only do Lüning, Vahrenholt and Curry mention the lack of acceleration signals in the data (whether based on satellite or tide gauge data):

    Look at the authors. Read the abstract. These are acknowledged sea level experts, much quoted by the Warmist media. Many are themselves avowed Warmists.

    Read the final two sentences of the abstract.

    “The reconstructions account for the observation that the rate of GMSLR was not much larger during the last 50 years than during the twentieth century as a whole, despite the increasing anthropogenic forcing. Semiempirical methods for projecting GMSLR depend on the existence of a relationship between global climate change and the rate of GMSLR, but the implication of the authors’ closure of the budget is that such a relationship is weak or absent during the twentieth century.”

    This puts massive holes in the entire premise (that the massive increase in CO2 emissions from human fossil fuel combustion is causing INCREASED warming, which would need to manifest itself as an acceleration signal).

    1. Kenneth Richard

      This puts massive holes in the entire premise (that the massive increase in CO2 emissions from human fossil fuel combustion is causing INCREASED warming, which would need to manifest itself as an acceleration signal).

      Actually, there’s a deceleration signal with added CO2 when looking at long-term tide gauge data, meaning that the opposite of what the climate models say should happen, happened.

      Holgate, 2007 
      “The rate of sea level change was found to be larger in the early part of last century (2.03 ± 0.35 mm/yr 1904–1953), in comparison with the latter part (1.45 ± 0.34 mm/yr 1954–2003).”

      A just-published paper (that will be reported in an article tomorrow) affirms the latter 1.45 mm/yr trend for the 1950s-present period continued through 2014.

      In other words, no anthropogenic signal in sea level rise.

      1. SebastianH

        Uh, exciting … one paper that turns around everything we know and destroys the entire AGW argument.

        Does that mean graphs like these are fake?

        Because I can’t see a higher sea level change in the early part of last century in the graph, can you?

        Or how about this graph?

        Doesn’t look like the rise was 30% faster in the first half of the 20th century than in the second half, does it?

        Or can you only come to a conclusion like that when you just take 9 stations you feel confident of tracking all stations in recent times and therefore are ok to extrapolate to the whole globe for the past?

        Looking forward to your paper and what creative interpretation you’ll offer for whatever it really says 😉

        1. Kenneth Richard

          Uh, exciting … one paper that turns around everything we know and destroys the entire AGW argument.

          Actually, it’s not just one paper that shows global sea levels have been rising at about 1.3 to 1.5 mm/yr since the 1950s. And no one claims that one paper “destroys the entire AGW argument” or “turns around everything we know” either. Those are just your made-up positions.

          Zerbini et al., 2017

          Our regional results, however, are in close agreement with the global mean rate, + 1.2 mm/year, published by Hay et al. (2015) which is currently being discussed by the oceanographic community

          McAneney et al., 2017

          Global averaged sea-level rise is estimated at about 1.7 ± 0.2 mm year−1 (Rhein et al. 2013), however, this global average rise ignores any local land movements. Church et al. (2006) and J. A. Church (2016; personal communication) suggest a long-term average rate of relative (ocean relative to land) sea-level rise of ∼1.3 mm year.

          Bezdek, 2017

          [G]lobal average sea levels have been rising at about 1.8 mm/yr. Although rates of absolute sea-level rise (rise due just to increases in ocean volume) can vary substantially from one location to another and change over time, the global average rate of 1.8 mm/yr. from 1961 to 2003 is a widely accepted global benchmark rate.

          I can’t see a higher sea level change in the early part of last century in the graph, can you?

          Perhaps it will become clearer on this graph (1,023 tide gauge stations), especially the bottom one which shows mm/yr rates for the 1900-2002 period.

        2. AndyG55

          And seb grabs a propaganda graph splicing the known mal-adjusted satellite fabrication onto the real data of the tide graphs.

          A mathematical and statistical inebriation only fit for base-level propaganda…

          Tide data shows no acceleration.

          Get over it, seb.

          1. yonason (from my cell phone)

            I don’ know, Andy. From what I’ve seen, nothing may be happening, but it’s for sure happening faster than ever! 😜

        3. Kurt in Switzerland


          You asked, “Does that mean graphs like these are fake?”

          Perhaps you just answered your own question.

        4. AndyG55

          And seriously, seb.

          scribbler is just that, an 8 year old with a pencil !!

          Just the sort of information that would suit you.

        5. yonason (from my cell phone)

          “…one paper that turns around everything we know and destroys the entire AGW argument.” – SebH

          Golly, you mean like Michael (one trick) Mann???

          Yeah, that profoundly affected how I view warmists. Until then I hadn’t realized what raving lunatics they were.

          Thanks, “Dr” Mann!

  2. Kurt in Switzerland

    The discrepancy between the satellite-derived GMSLR figure of 3.3 (or 3.0) mm/y and the tide gauge average of approx. 1.7 mm/y adds up to a considerable difference after 27 years. (1990-present).

    That’s 1.3 – 1.6 mm more per year for the satellite data vs the tide gauge data, according to the U of Colo. published estimates.

    After 27 years, this would work out to 35-43 mm discrepancy. At some point, someone needs to reconcile the two. Quite likely, the satellite estimate will be revised downwards yet again in the coming years.

    1. Christopher Hanley

      Prof Humlum @ climate4you discussing the difference between the satellite data and tidal gauges:
      “… the rather marked difference between the two data sets has still no broadly accepted explanation, but some of the difference is likely due to administrative changes introduced into the raw data obtained by satellites …
      … another factor that may explain some of the difference between tide-gauge and satellite data is probably that while any temperature-driven volume expansion is recorded by the satellites, this change is not affecting tide-gauges at coastal locations, as the water depth here decreases towards zero …”.
      Tidal gauges measure changes in volume due to loss of grounded glacier mass while the satellites also measure temperature-driven volume change.

      1. SebastianH


        1. AndyG55

          Wow, and just when I thought your comments couldn’t get any emptier. !!

  3. AndyG55

    OT, under the heading of “green myth” and “plenty of CO2”

    China’s CO2 emissions GREW by around 4% last year.

    Well Done China..

    The world’s plant life needs that CO2

  4. AndyG55
  5. AndyG55

    OT, rather good fun watching the Dumbocrat faces in this video of snippets from POTUS’s SOTU address

    Never seen such sour, sulky, despondent looks. 🙂

    And not one mention of “climate change”. 🙂

    1. SebastianH
      1. John M

        Gee, I searched your link for the phrase “climate change” and didn’t find anything.

        Did you post the wrong link?

        1. tom0mason

          John M,
          No the auto-bot is on ‘distract’ mode as he has nothing in the database that is relevant to the topic in hand.

          Unfortunately he may well succeed.

        2. John M


          Of all the Trump-bashing “Fact Checkers” out there, Seb managed to stumble on to one that even other Fact Checkers think is bunk.

      2. AndyG55

        poor seb .. you seem so sour, sulky, and despondent.

        diddums. 🙂

      3. RAH

        “Fact Checkers” are just another arm of the establishments media. They were a fabrication by the establishment that was needed because the trust in the veracity of their regular media was and is still in decline. Now the belief in the veracity of the fact checkers has declined also. Proof you say? The election of Donald Trump when all the leftist “Fact Checkers” were continually trying to paint him as a habitual liar.

        It was quite noticeable that the very first place the left turned to after their miserable optics at the STOU address was “Fact Checkers”.

        I suspect that the effect from the democrats sitting on their hands refusing to clap or stand even as the POTUS noted the services and sacrifices of the first responders, military, and police and good economic news will be about the same as the NFL has experienced supporting the players in their Anthem protests. Not good!

        BTW Seb, even CBS had to report that their poll showed 75% of those that watched the STOU address liked it. Trump soared while the democrats and their “resistance”, already in a stall went into a tail spin. Would not be surprised if looking back, even the leftist press will be forced to admit that this was a turning point in the Trump administration.

  6. Latest Data Show NO SEA LEVEL RISE ACCELERATION Since 1993…Coasts: Less Than 2 Millimeters Rise Annually! | Un hobby...

    […] P Gosselin, January 31, 2018 in […]

  7. ATheoK


    Judith Curry’s part 2: is located at this link:

    The link you provide in the article points to Part 1:

    Good article!

  8. Scientists Bewildered as Climate Crisis and Sea Level Rises Fail to Appear | Principia Scientific International

    […] Over the past months, a spate of scientific papers published shows sea level rise has not accelerated like many climate warming scientists warned earlier. The reality is that the rise is far slower than expected, read here and here. […]

By continuing to use the site, you agree to the use of cookies. more information

The cookie settings on this website are set to "allow cookies" to give you the best browsing experience possible. If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this. More information at our Data Privacy Policy