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Historical records may underestimate sea level rise

October 19, 2016

By Paul Homewood




From the “Pay us enough money,  and we’ll prove that it’s worse than we thought” Dept of Climate Science:



A new NASA and university study using NASA satellite data finds that tide gauges — the longest and highest-quality records of historical ocean water levels — may have underestimated the amount of global average sea level rise that occurred during the 20th century.

A research team led by Philip Thompson, associate director of the University of Hawaii Sea Level Center in the School of Ocean and Earth Science and Technology, Manoa, evaluated how various processes that cause sea level to change differently in different places may have affected past measurements. The team also included scientists from NASA’s Jet Propulsion Laboratory, Pasadena, California, and Old Dominion University, Norfolk, Virginia.

“It’s not that there’s something wrong with the instruments or the data,” said Thompson, “but for a variety of reasons, sea level does not change at the same pace everywhere at the same time. As it turns out, our best historical sea level records tend to be located where 20th century sea level rise was most likely less than the true global average.”

One of the key processes the researchers looked at is the effect of “ice melt fingerprints,” which are global patterns of sea level change caused by deviations in Earth’s rotation and local gravity that occur when a large ice mass melts. To determine the unique melt fingerprint for glaciers, ice caps and ice sheets, the team used data from NASA’s Gravity Recovery and Climate Experiment (GRACE) satellites on Earth’s changing gravitational field, and a novel modeling tool (developed by study co-author Surendra Adhikari and the JPL team) that simulates how ocean mass is redistributed due to ice melting.

One of the most fascinating and counter-intuitive features of these fingerprints is that sea level drops in the vicinity of a melting glacier, instead of rising as might be expected. The loss of ice mass reduces the glacier’s gravitational influence, causing nearby ocean water to migrate away. But far from the glacier, the water it has added to the ocean causes sea level to rise at a much greater rate.

During the 20th century, the dominant locations of global ice melt were in the Northern Hemisphere. The results of this study showed that many of the highest-quality historical water level records are taken from places where the melt fingerprints of Northern Hemisphere sources result in reduced local sea level change compared to the global average. Furthermore, the scientists found that factors capable of enhancing sea level rise at these locations, such as wind or Southern Hemisphere melt, were not likely to have counteracted the impact of fingerprints from Northern Hemisphere ice melt.

The study concludes it is highly unlikely that global average sea level rose less than 5.5 inches (14 centimeters) during the 20th century. The most likely amount was closer to 6.7 inches (17 centimeters).

“This is really important, because it provides answers to the question about how melt fingerprints and the influence of wind on ocean circulation affect our ability to estimate past sea level rise,” said Thompson. “These results suggest that our longest records are most likely to underestimate past global mean change and allow us to establish the minimum amount of global sea level rise that could have occurred during the last century.”


To be fair, nobody would seriously suggest that we can accurately calculate global sea level trends from a relatively small number of tidal gauges, given regional differences, land movements, ENSO changes and the rest.

At this juncture, you may recall that, when satellite measurements took over from the aforesaid tidal gauges in 1993, it was claimed that sea level rise had miraculously accelerated. This despite the fact that no serious scientist, (which lets off climate scientists), would even think about splicing one dataset on to to a totally different one, and then claiming that the differences had any significance at all.

So, maybe this new approach shows that, since 20th rise was greater than thought, the claimed acceleration simply does not exist.


But that is to generous.

Let’s take a closer look at the Abstract:





Now home in on this bit:

“but based on the locations of these gauges, we show that the simple average underestimates the twentieth century global mean rate by 0.1 ± 0.2 mm/yr.”


Note that the error margin is twice the claimed trend!!

Would any real scientist make such claims, when his results are statistically meaningless?

Would any peer reviewer worth his salt accept such rubbish?

Would any authoritative scientific journal publish such nonsense?

And would a serious space agency, as NASA used to be, give it any credence at all?

Only in the world of climate science!!

  1. markl permalink
    October 19, 2016 10:12 pm

    History proves us wrong? Don’t worry, we’ll fix that. Blatant corruption of land temperature then sea temperature wasn’t enough so now they’re going for sea level. It’s a perverse reality they are attempting to create and nothing more. People realize they are wrong and doing nothing more than attempting to cover their tracks. Don’t they?

  2. catweazle666 permalink
    October 19, 2016 10:20 pm

    So just like “Global” temperatures, the majority of increase takes place in places that lack the instruments to measure them.

    What a surprise!

    As to 0.1 ± 0.2 mm/yr, only in Climate “Science”. Didn’t these “scientists” ever study science when they were at school?

  3. October 19, 2016 10:30 pm

    The Gavin Schmidt Article in the Mail has had the comments removed and disabled
    ..Usually Mail’s comments are open unless need

    You saw the recent hardcore Milo video on why LeftMob media clo-down comments

    • Broadlands permalink
      October 20, 2016 12:40 am

      Fascinating to see Dr. gavin say in the Mail article: ‘The planet is getting warmer. It’s important for what it tells us about the future”

      A few weeks, days? ago the same Dr. Schmidt admitted to us about CO2 “In my opinion we won’t ever see a month below 400 ppm.” His former boss added: it’s “wishful thinking”.

      Those might be frank admissions that the future is what Nature’s “natural variations” decide it will be? That NASA’s finest experts can do nothing to save us all? But… they will keep trying to keep us scared. It pays their salary as well as all those at the other locations where the data are adjusted?

  4. Curious George permalink
    October 19, 2016 11:18 pm

    Simple. Let’s adjust inconvenient tide gauge records.

  5. Dave N permalink
    October 20, 2016 12:37 am

    Beyond comical: the error margin shows that they could have *overestimated* sea-level rise. These clowns would have better luck in a circus.

  6. ColA permalink
    October 20, 2016 2:19 am

    They obviously reviewed this video before they put out their paper so they could make their claim!!

  7. John F. Hultquist permalink
    October 20, 2016 2:30 am

    Not all research leads to significant, or even interesting, results.
    Nonetheless, funded research almost always (maybe always) leads to publication. Grants include money for drafting of maps, typing, copying and so on. Travel expenses are there to go to exotic (or not) places to read/deliver results, maybe in the form of a big multi-colored poster.
    Many universities provide “seed” money/grants that are expected to lead to bigger grants from external funding. These external grants frequently go to those with a track record of accomplishing research that gets published. Hope is that the publication gets “cited” by others, thereby proving the wise decisions of those that provided the grant.
    In the current case, the research might have been thought to be more important before it was done than after.
    Another way of looking at it is that one or more graduate students received a year’s worth of money and other goodies, such as a trip to that exotic place, and a chance to “network” so they too can learn how to spend other people’s money.
    I’ve seen my money wasted by others in worse ways.
    Personally, I prefer to spend it on bird dogs, horses, wine, women — not necessarily in that order.

    • October 20, 2016 12:26 pm

      I worked on vegetation associated with diabase dikes and sills in the Gettysburg Basin of PA for my PhD. The 2 types of diabase there are mafic but do not contain toxic levels of olivine as do some farther south. One of my committee members questioned my not having any endemic species as would be found with the olivine rich rock areas . Instead, my vegetation was normal assemblages found in piedmont, PA. However, there was some rather unique locations due to the fracturing of the diabase and underlying clay soils formed. After the printouts from the computers at UNC, I finally figured out what all those little spots (my plots) meant when I laid out my color-coded index cards for each plot on my bed in the same order. Voila. It was water movement and the depth of fracturing along with nearness to the edges in the case of the dikes which affected the coarseness of the soils and drainage.

      It might not have been high tech, but it worked. And my major professor, the late Dr. Albert E. Radford (principal author of “The Flora of the Carolinas”). He told that committee member, disappointed by the lack of endemic flora, that “no” was an answer.

      One amazing aspect became apparent in the fall when Dr. and Mrs. Radford came from NC to visit my research area. Big Round Top (of the Civil War Battle of Gettysburg fame–my g grandfather was there for the event), was ringed all around at a certain level with tulip poplar (Liriodendron tulipifera). Normally, it is a cove hardwood of the north and northeast facing slopes, and here it was bold as brass on the south and west slopes forming a ring around the mountain. That was where a fracture line in the sill that is Gettysburg lies.

      Science deals with what IS and interpretation of it.

  8. RAH permalink
    October 20, 2016 3:57 am

    And people still drive on the West side highway in NYC. Point being they can do all the math they want because I’m beyond taking the stuff they publish seriously. Show me the effects in the real world otherwise all the calculations and explanations of methodology are meaningless academic drivel.

  9. October 20, 2016 4:20 am

    So the majority of satellite sea level rise is in areas where there is no coast and no people. So then it also is not a problem, ships rise with the sea. Coastal sea level rise has been modest, and no reason for worriyng, unless you like horror science fiction where the antarctic icecap plunges suddenly into the southern ocean.

    • AndyG55 permalink
      October 20, 2016 4:37 am

      If this disparity in sea level rise continues, there will soon be huge great bulges of water off Japan and off the east coast of south America. Ships will have to go around because it will be hard to sail uphill…. although the ride down the other side would be fun.

  10. October 20, 2016 6:06 am

    You have to love that 0.1 – 0.2 mm/yr correction on speculative data that then returns to observed data when taken from a guesstimated amount of 1.4 and is then ‘corrected’ to 1.6. That must use the current iteration of New Math.

  11. tom0mason permalink
    October 20, 2016 7:14 am

    “…Earth’s changing gravitational field, and a novel modeling tool …”
    … is a new computer generated super book that’s light in mass but somehow is very heavy, and marketed as a simulated novel called —

    ‘”Tides of Gravity” by the Wat T.H.E. Dickens team.’

    Latest sales gauges report uptake is believed to be gathering momentum but exactly how remains a mystery.

    • October 20, 2016 8:18 am

      That phrase “novel modelling tool” was what finally convinced me that this was some arcane April Fool article that got missed seven months ago!

  12. October 20, 2016 8:03 am

    ‘But far from the glacier, the water it has added to the ocean causes sea level to rise at a much greater rate.’

    That must be some humongous glacier to do that.

  13. A C Osborn permalink
    October 20, 2016 11:17 am

    Measuring in millimetres when all waves are bigger than that, what could possibly be wrong with that?

    Paul, I think you will find at the onset of the Satellite Sea Surface Measurement, the Satellites showed that the sea level was actually falling, but that was soon corrected by taking them out of commission.
    They then got the answers that they wanted.

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