Brief Note by Kip Hansen — 10 January 2020
Those who follow the GMSL data from NOAA may have noticed an oddity in the data from December 2019. The oddity was seen in the .png file available at the bottom of the web page for NOAA’s Laboratory for Satellite Altimetry. As of 31 December 2019, the graphic looked like this:
One can see that there is what appears to be missing data at the upper right. Checking the .csv data file on the same day reveals that there are in fact missing data points:
My email enquiry has resulted in a correction and an explanation:
Subject: Re: Data Break in STAR GMSL data Date: Fri, 10 Jan 2020 15:48:56 -0500 From: Eric Leuliette – NOAA Federal To: Kip Hansen Dear Kip,
Thanks for bringing the gap in the global mean sea level data to my attention. For 2 cycles of Jason-3 data, our database was missing some data due to a script failure. I’ve fixed the database and rerun the mean sea level data. The replacement files are on our web site now.
Please let me know if you have any other questions or concerns.
Eric
____________________________________________________________
Eric W. Leuliette, PhD
Branch Chief
Laboratory for Satellite Altimetry
National Oceanic and Atmospheric Administration
NOAA Center for Weather and Climate Prediction (NCWCP)
xxxx (some contact data removed – kh )
______________________________________________________________
The contents of this message are mine personally and do not necessarily reflect any position of NOAA.
The updated chart now shows:
The missing data points have been filled in — but, unfortunately, there is a new problem!
The latest data points, from the middle of December, should be:
| 2019.592 | 61.81 | |||
| 2019.619 | 66.11 | |||
| 2019.646 | 69.41 | |||
| 2019.673 | 69.71 | |||
| 2019.7 | 70.31 | |||
| 2019.727 | 71.11 | |||
| 2019.755 | 69.81 | |||
| 2019.782 | 71.81 | |||
| 2019.809 | 72.01 | |||
| 2019.836 | 69.71 | |||
| 2019.863 | 72.81 | |||
| 2019.89 | 70.81 | |||
| 2019.917 | 68.81 | |||
| 2019.945 | 70.21 | |||
| 2019.972 | 66.71 | |||
| 2019.999 | 65.61 | |||
| 2020.016 | 62.01 |
Yet the .png graphic file shows values for January 2020 (2020.016) at 69-70mm, not the 62.01mm given in the .csv data file.
I have sent another enquiry….
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Author’s Comment:
Why does this matter? It doesn’t matter that much, except that these are the official NOAA SLR data and graphics — they are used in all sorts of science and journalism — and they simply ought to be correct — or, if we can’t guarantee that they are correct, they should at least agree with one another. If they do not, then there is something wrong, as Eric has stated, with the scripts that produce either the .csv data files or the graphics.
On the upside, Eric Leuliette at NOAA is responsive and helpful — recognizing, acknowledging and correcting the missing data.
Still, the current version of the graphic shows a steep rise with a tiny little hook at the top — when the data shows that it ought to have a big hook back down to 62mm — either the data or the graphic is wrong. I’ll let you know.
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Kip,
How anyone can believe the satellite data is beyond me! Data from tide gauge on stable land are in the range of 1.4 to 2 mm/year, including those on islands surrounded by deep oceans. Satellite precision is very poor, which includes GPS data. Fort Denison, Sydney NSW, has had a SLR of about 0.7 mm/year for more than a century, so if anything, the site may be rising. Yet the GPS over 8 yrs & 7 months gives -0.33 +/- 0.25 mm/yr., in other words it is sinking! Not possible! See this link:
https://www.sonel.org/spip.php?page=gps&idStation=2405
The relevant part of the page would not insert.
The satellite data is no better. Both have annual and other oscillations. If anything one might presume that their “corrections” were made to match the USA coasts which are sinking as the northern part is still rising after the glacial melt.
Paul –> lots of things to say about SLR and the data sets that support it. If yo haven’t already –see m other SLR essays here at WUWT.
Has anyone ever come across a study which correlates this satellite altimetry for Sea level (showing approximately 3.3 mm/yr SLR) with the Global Tide Gauge Network which shows 1.7 mm.yr? These two data sets should be easily correlated via satellite altimetry measurements never the tide gauge locations. Satellite Altimetry is a very challenging measurement with significant averaging required to reduce the uncertainties, and the best calibration source should be the existing tide gauges.
Bob ==> I have been writing about this for some time. What you suggest is sensible but not yet possible.
To accomplish that, we need a whole lot more “CGPS@TG {same structure]” stations around the world each running for at least three or four years.
Eventuall we will get there.
“…our database was missing some data due to a script failure…”
I have a fairly good idea how this “database” is setup and run. Someone wanted some “automation”, a scheduled “script” is run and is expected to run without error. No-one running the system actually does any monitoring or auditing. I have seen this with “databases” at NIWA in New Zealand. Stuff is setup, “automation” is turned on and no-one checks anything to see if the job it is supposed to be doing is actually being done. How many other “databases” in climate “science” are run this way?
Patrick MJD ==> Yes, Eric at NOAA confirmed that this was the case.
I have been a web professional and one of my main bug-a-bears has been the refusal of even very professional web teams to assign an “editor” whose job consists of actually looking at their web site, every page, every day.
The New York Times doesn’t even do it for their web front page!
How many of these mistakes have gone unnoticed?
wadelightly ==> I suppose that they mostly get eventually caught — they are viewed by a lot of other organizations, many of whom use the same basic data to produce their own data sets and graphics. When there are major differences, someone notices and they try to sort them out.
Unfortunately, the group think about the validity of millimeter-scale SLR has them all befuddled.