Guest Essay by Kip Hansen (with help from Steve Case)
Prologue: I have been writing recently about Sea Level Rise, both as particular local examples ( Guam, Canton, Miami, New York, and NY/NJ ) and in the series SEA LEVEL: Rise and Fall, of which this is the fourth installment.
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How does one get a rise out of nothing?
He [Steve Nerem] presented the as-yet-unpublished analysis on 13 July in New York City at a conference sponsored by the World Climate Research Programme and the International Oceanographic Commission. …. Nerem’s team calculated that the rate of sea-level rise increased from around 1.8 millimetres per year in 1993 to roughly 3.9 millimetres per year today as a result of global warming.
Hmmmm….let’s see what NOAA says on the matter, as of yesterday:
Now, that’s odd. NOAA NESDIS-Star [National Environmental Satellite, Data, and Information Service; Center for Satellite Applications and Research] doesn’t show anything like a sudden acceleration from 1993 data (right on NOAA’s 3.0 ± 0.4 mm/yr) to present — same exact trend line, the same figure given in the image title.
So, first things first — who is R. Steven Nerem?
Steve Nerem is a Sea Level Rise Alarm Evangelist — there is no other appropriate description. I have no doubt that he truly believes in his Cause, after all, he has traveled the world for the last year delivering the same presentation — exact same abstract — in San Francisco (Dec 2016), Bologna (Feb 2017), New York (July 2017), Miami (Oct 2017), and New Orleans (Dec 2017). Nerem is one of the co-authors of the infamous, three-years-late 2007 Comment in the journal Global and Planetary Change attempting to refute Nils-Axel Mörner’s 2004 paper (two links there) in the same journal. I covered the Mörner/Nerem/ Mörner exchange in SEA LEVEL: Rise and Fall – Part 3.
Steve Nerem was also co-author of the blatantly alarmist Washington Post article in May 2016, “10 things you should know about sea level rise and how bad it could be”, in which it is stated “Scientists estimate that if it warms by about 4 to 5 degrees Celsius (7.2 to 9 degrees Fahrenheit), which is projected to happen by the end of the century if we don’t act on climate change, then all the ice will eventually melt. That’s 230 feet of sea level rise.”
Dr. Nerem’s travelling show is described in a July 2017 Nature.com article titled “Satellite snafu masked true sea-level rise for decades”. The article relates details from Nerem’s oft-repeated presentation saying:
“As the Greenland ice sheet thaws, it is helping to raise the world’s sea levels.
The numbers didn’t add up. Even as Earth grew warmer and glaciers and ice sheets thawed, decades of satellite data seemed to show that the rate of sea-level rise was holding steady — or even declining.”
“Now, after puzzling over this discrepancy for years, scientists have identified its source: a problem with the calibration of a sensor on the first of several satellites launched to measure the height of the sea surface using radar. Adjusting the data to remove that error suggests that sea levels are indeed rising at faster rates each year.”
“Nerem’s team calculated that the rate of sea-level rise increased from around 1.8 millimetres per year in 1993 to roughly 3.9 millimetres per year today as a result of global warming. In addition to the satellite calibration error, his analysis also takes into account other factors that have influenced sea-level rise in the last several decades, such as the eruption of Mount Pinatubo in the Philippines in 1991 and the recent El Niño weather pattern.”
“If sea-level rise continues to accelerate at the current rate, Nerem says, the world’s oceans could rise by about 75 centimetres [ 29.5 inches] over the next century. That is in line with projections made by the Intergovernmental Panel on Climate Change in 2013.”
If this sounds to you a lot like what Nils-Axel Mörner has been saying all along, that SLR alarm has its origins in the ad hoc– after measurement — adjustments and ‘corrections’, you may have something.
Here’s the graph from Nerem’s CIRES faculty page:
In the text of the page, it states “We must also carefully assess the measurement errors and the influence of decadal variability on a relatively short 25-year record. While we are still completing this research, it appears that long-term sea level rise has accelerated from roughly 2 mm/year in the mid-1990s to 4 mm/year today (2017).” Of course, that statement is a little loosely worded — making it seem that the trend of the early part of this graph is around 2 mm/yr. In reality he is referring to the long-term, 20th century tide-gauge-based trend of 1.8-2.0 mm/yr in the first instance and to his “roughly 3.9 mm/yr” from his unpublished re-analysis. Notice that the trend line, instead of the usually seen straight line from 1993 to present is here represented as a curved acceleration trend.
The generally accepted view of these two figures is shown in this image:
Just last year, Nerem co-authored a paper titled “Is the detection of accelerated sea level rise imminent?” ( published in Aug 2016, just four months before Dr. Nerem hits the lecture trail ). The abstract concludes with “…a detectable acceleration is likely to emerge from the noise of internal climate variability in the coming decade.” and goes on to say “Over the 23-year time series, it shows that GMSL has been rising at a rate of 3.3 ± 0.4 mm/yr, but with notable inter-decadal variability. Our current best estimate of the rates during the first (1993–2002) and second (2003–2012) decades of the altimeter era are 3.5 and 2.7 mm/yr. There are several theories to explain this variability, but here we present an additional explanation, with important implications for anticipated near-future acceleration.”
They got real busy, and according to the Nature.com report found that elusive acceleration by December 2016.
How did they do it?
Easy, apparently. You see, the modern portion of the satellite sea level record is too widely shared to make any major changes — it is difficult to change it or adjust it — it has already exceeded its adjustment-budget, any more adjustment and it will go broke — so they [no laughing now ] again adjusted the past.
I will use NOAAs images and data to show how this was done:
This blinking image shows the usually viewed NOAA-NESDIS-STAR satellite SLR record graph, up to the end of 2017, colored for the four satellite missions that gathered the data. The second image, overlaid, shows the latest data from NASA JPL that includes the “updates” that Nerem is discussing. What we see here is that through a series of adjustments, they have raised the left end of the graph, the TOPEX Altimeter A data, by approximately 3-to-5 mm and made some very slight changes in the Altimeter B data. Raising the left end of the graph — 1993-1999 — then allows them to change the trend line from a slope of 3.0 to 3.18 mm/yr.
Nerem has one-upped that and used the same adjusted data to draw a curving acceleration trend which he claims shows 3.9 mm/yr.
Five (5) millimeters, the maximum change to any data point in the update, is a tad more than thickness of 3 US dimes stacked atop one another or, in Europe, the thickness of two 1 Euro coins stacked. In inches, 2/10ths of an inch. The dreadful, to-be-feared acceleration of Sea Level Rise is built out of the dubious corrections to TOPEX Altimeter A data alone — a full five mms, of six years of “bad data” from 1993 – 1999. Data which, if poor, should have been thrown out instead of adjusted to match a predetermined narrative.
Nothing whatever changes in the more dependable data from 1999 to Jan 2018. According to NOAA that 19 year record has not been changed at all and still shows exactly the same trend that it has always shown — approximate 3.0 ± 0.4 mm/yr. And nothing changes the fact that the latest altimeter data from new, improved Jason-3 show virtually zero SLR for over 2 years now — ZERO. We’ll have to wait and see what the enthusiasts do to make that match their narrative.
They have created an acceleration out of nothing.
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PS: I think I’ll stick with this, the latest from NOAA:
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I am sorry to have to inform you, though, that it is worse than we thought. You see, the data used in determining satellite-based SLR in the above data and graphs, is not really sea level rise. That is, it does not represent (and never has) an actual increase in the level of the sea surface above the geoid (or, easier to imagine, increasing distance from the center of the Earth). Real sea level rise is reflected in a rise in Global Mean Sea Surface Height. But Global Mean SLR, as calculated by Colorado’s Sea Level Group, NOAA, and other SLR groups is a concept — not a measurement. I once used the phrase “imaginary number” to describe this type of non-physical metric — a number said to represent something in the real world, but in actuality, being something different altogether. I discuss in general how this comes about in an essay “What Are They Really Counting”. SLR satellite data includes things such as the “GIA Adjustment” — which is the amount of SLR that there would have been if the ocean basin hadn’t increased in volume and other additions and adjustments that cannot actually be found manifested in any change to the physical Sea Surface Height. But that’s a torrid tale for another time.
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Series Take Home Messages:
- Overall, the seas have been rising, slowly and inexorably, since the end of the last Ice Age, with some blips and bumps along the way. In general, they will continue to do so for the foreseeable future — at somewhere between 4-12 inches [10-30cm] per century. This rate is an imminent threat to populated areas built nominally at today’s existing sea level.
- It does not seem that sea levels are rising dangerously or rapidly, nor is the rise accelerating, on a global scale — though our ability to measure global changes at these very small (millimetric) magnitudes is highly questionable.
- If Morner (and his 101 colleagues of the INQUA Commission) are correct, there has not been much actual sea level rise at all over the last 25 years (the satellite altimetry era).
- All of the above could mean that the constant drumbeat of doom regarding rising sea levels is based on the same sort of Computational Hubris that has brought us “average global temperature anomaly” in place of average global surface temperature.
- The touted “acceleration” in SLR is an alarmist talking point created from the disconnect between (mostly) tide-gauge data unadjusted for Vertical Land Movement at the tide-gauge site (vertical movement of the tide gauge itself) and the satellite altimetry data — a data set almost hopelessly confounded by measurement and physical elements orders of magnitude greater than the signal being sought.
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Author’s Comment Policy:
I am always happy to read your comments and to try and answer your on-topic questions.
Sea Level Rise is an ongoing Scientific Controversy. This means that great care must be taken in reading and interpreting the past data, new studies and especially media coverage of the topic [including this series!] — bias and advocacy are rampant, opposing forces are firing repeated salvos at one another in the journals and in the press [this essay is about the latest salvo from Steve Nerem] and the consensus may well simply be “an accurate measure of the prevailing bias in the field.” (h/t John Ioannidis)
Sea Level Rise is being blatantly used as a scare tactic by advocates of Catastrophic Anthropogenic Global Warming/Climate Change. Sea level Rise — by now well-known to the general public as less than a foot per century — has been supplanted by Dangerous Sea Level Rise Acceleration as a talking point.
Steve Case brought the latest adjustments to my attention and supplied links and graphs — many thanks, Steve.
If you are speaking directly to me in your comment, begin it with “Kip…” so I am sure to see it.
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