I’ve been watching with interest and concern some of Steve Goddard’s postings on Envisat on the abrupt changes in their recent sea level data. To me, something didn’t seem quite right, and I expressed concerns privately along those lines that I didn’t know the causes of what appear to be recent unexplained “adjustments” in the recent data. It seems ENVISAT has given up the ghost. So, it is possible it has been sending faulty data and they have not noticed. Here, he shows this graph which seems quite problematic:
This is like what has happened with the AQUA AMSRE failure and the failure that we had to point out to NSIDC (where Dr. Walt Meier famously exclaimed it “wasn’t worth blogging about” only to have to later issue corrections themselves) that the DMSP satellite they were using had issues. Whether this is permanent or not remains to be seen. After 10 years of service, Envisat has stopped sending data to Earth. ESA’s mission control is working to re-establish contact with the satellite.
Via our friend Ecotretas :
I read in the news today that connections have been lost with the Envisat satellite. ESA has already confirmed it too, but reading the latest Mission Operations News, it seems it would be predicted for a satellite that had only been planned for a five year mission.
So I ran to see how the sea level graphs had finished, and to my biggest surprise, the graph from AVISO had changed dramatically! I recall seeing it about a week ago, with totally different values! From an historical perspective, several older graphs can be seen in a post 9 months ago (in Portuguese), or compared with other satellite measurements in this WUWT post. Please compare the graph 9 months ago on the left, and the more recent one on the right (click to zoom):
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Notice that the slope has gone up from 0.76 mm/year to 2.33 mm/year! This manipulation, which has no other name, has been justified by Aviso with the following notes:
- Envisat time series extended before 2004 starting from May 2002.
- Envisat V2.1 GDR reprocessed data used. The new standards are also detailed in the table “Processing and corrections”.
- Instrumental correction sign corrected (impact of around +2mm/year). The error detection and impact on data is detailed in:
- Envisat 2011 yearly report, A. Ollivier & M. Guibbaud, soon on the Aviso website
- Envisat Reprocessing impact on ocean data, A.Ollivier & M. Guibbaud, soon on the Aviso website
- A.Ollivier et al. 2012, Envisat ocean altimeter becoming relevant for mean sea level long term studies? (submitted in Marine Geodesy)
- new NetCDF CF format in the products and images selection interface
Now, this looks like a small part of the Envisat mystery. Please check that the older graph starts in 2004, but the newer graph starts in mid 2002! Notice that in the newer graph, the 2002 and 2003 values were much higher that those of 2004, and that the highest values of 2003 were not surprassed till late 2008. Now imagine why they were not there in the older graphs, and how being there would create a trend probably very near to ZERO!
The last image, the above one on the right, that’s on the AVISO site is dated “Tue, 10 Apr 2012 09:14:03 GMT”, so clearly has been put there after the satellite failed, which occurred last Sunday. No doubt that the hiding the decline was already planned, but probably was executed swiftly after the fail. Strangely, the last color image taken by the satellite was above Portugal, which is obviously a coincidence. But it looks like it’s mysteries have only started…
If you don’t even know WHEN an instrument stopped working, the only correct action is to throw out every bit of data from that instrument.
http://www.theregister.co.uk/2012/04/11/bering_sea_ice_cover/
‘The amount of floating ice in the Arctic’s Bering Sea – which had long been expected to retreat disastrously by climate-Cassandra organisations such as Greenpeace – reached all-time record high levels last month, according to US researchers monitoring the area using satellites.
The US National Snow and Ice Data Center announced last week that ice extent in the Bering for the month of March has now been collated and compared, and is the highest seen since records began.
…
The NSIDC boffins add, however that overall the Arctic ice – while up on recent years – is below the average seen since records began in 1979. In fact, according to the Cryosphere Today website run by the Polar Research group at Illinois uni, it’s down by 443,000 square km. However the sea ice around the Antarctic coasts is above average by 452,000 km2, so overall the planet’s sea ice is at the moment slightly above average in extent – and in the Bering Sea, the walruses, seals and polar bears can quite literally chill out in comfort. ®’
All satellite data has to be ‘processed’ – that’s a given, I presume? – but wouldn’t it be more appropriate to have at least two or three independent teams doing the ‘processing’ ? Do they do this? I don’t know – but the bottom line is that he who controls the satellite and data processing, surely controls the ‘findings’. Note, I am not a conspiracy theorist as such – but when stuff like temp data adjustments, station losses, etc, etc and now this – it doesn’t command much faith!
Cooked to order. How do you like your books? Well Done? We recommend Rare.
TomRude says:
April 12, 2012 at 2:50 pm
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Thanks but why didn’t they include NOAA tide gauge data to check the recalibration? They’ve adjusted sea level up by 1.8mm/year without any confirmation? Hopefully I’m missing something important.
Am I the only one losing faith in “all” our satellite data ?
If, for no other reason, that it is so short term and must constantly be adjusted to real world observations.
Just say’n 🙁
I wouldn’t put it past them to have shot down the messenger (satellite) so they could rewrite the data to better fit their models. Wasn’t there a mysterious burning object recently that was identified as space junk on re-entry?
Both hotlinks “Envisat V2.1 GDR reprocessed data used. The new standards are also detailed in the table “Processing and corrections”.” give a 404 error. It just seems strange that it takes all this time to prpoerly calibrate a not inexpensive system like this. My guess is this adjustment has a greater error then what it is they are attmepting to correct.
Could someone with the appropriate computer skills resize and align the two graphs so the changes are easier to compare. Steve’s graph from the first link seems to have been resized but for some reason he chose to only align the horizontal axis.
Also, while the changes are dramatic and the typical lack of clear explanation frustrating, an eyeball look at the Colorado data would suggest that since 2002, this new interpretation of the Envirosat data is actually much closer then it was before the adjustments.
Terry
I just love the expression “reprocessed data”!!! The perfect solution when the measurements or data don’t fit the theory! No doubt ‘Reprocessing Data 101″ will be included in future graduate courses.
Perhaps there is a travesty in there somewhere. It might be worth a PHD to find it.
I’ve read a number of articles that attributed the drop in ocean levels to heavy rains. So does this still hold?
And if Envisat data doesn’t agree with NASA’s data, I wonder if NASA is going to ‘tamper’ with their ocean level data so it somewhat matches Envisat?
This is really bad if true, did they also adjust (muck about with) the tidal gauge data? 1981 2009 sea level readings for the 3 gauges Suyts was looking at showed a drop in sea level until additional data was added 1.5 years after the fact.
http://suyts.wordpress.com/2012/02/20/canadian-west-coast-tidal-gauge-measurements/
This says it all:
http://youtu.be/pzHdxhpDq6A
Makes me think of the movie Space Cowboys…
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Made me think of the Steve Miller version
“Same old story with a new set of words” (really).
Even if there was some kind of drift in the readings it is hard to see how this could introduce any kind of significant error. Weren’t the constantly calibrating sea levels to their measured land elevations? What else would they be calibrating to? And if they were calibrating to the land then any drift would be compensated for in real time, whether it came from orbital decay or from sensor drift.
What am I missing? This kind of major reanalysis would seem to be well outside the bounds of any reasonable adjustment unless they are saying that they had their whole calculational scheme was way off from the beginning. I see no way that it could be a legitimate compensation for any kind of decay. It would have to be a decay that affected measurements over the sea but not the land. Is that even possible?
Are you calling the sea level data “Bob”?
Pardon me, but why is my comment still awaiting moderation after so long a time, nearly an hour?
“onlyme says:
Your comment is awaiting moderation.
April 12, 2012 at 3:10 pm
http://www.theregister.co.uk/2012/04/11/bering_sea_ice_cover/
‘The amount of floating ice in the Arctic’s Bering Sea – which had long been expected to retreat disastrously by climate-Cassandra organisations such as Greenpeace – reached all-time record high levels last month, according to US researchers monitoring the area using satellites.
The US National Snow and Ice Data Center announced last week that ice extent in the Bering for the month of March has now been collated and compared, and is the highest seen since records began.
…
The NSIDC boffins add, however that overall the Arctic ice – while up on recent years – is below the average seen since records began in 1979. In fact, according to the Cryosphere Today website run by the Polar Research group at Illinois uni, it’s down by 443,000 square km. However the sea ice around the Antarctic coasts is above average by 452,000 km2, so overall the planet’s sea ice is at the moment slightly above average in extent – and in the Bering Sea, the walruses, seals and polar bears can quite literally chill out in comfort. ®’ ”
Have i violated a policy or something?
[REPLY – Sounds like a clear case of violating the policy of only posting when a moderator is checking. ~ Evan]
[Reply #2: Your comment has now been posted twice. Sometimes WordPress will assign a comment to the Spam folder if it even has one link. We don’t check the Spam folder nearly as often as we approve comments. ~dbs, mod.]
Going to archive.org shows someminor changes in the way they read the slope. In 2008 they started the list at 1997 at about 2cm, the current one starts at zero. The slope is much the same at 3.052 vs 3.17. I don’t have time to look further, but if anyone is interested here is the link
Sorry, never mind, evidently a wordpress/opera/operator error glitch. I had to ctrl/f5 refresh to see the comment posted.
I had posted on the lack of updates to the satellites just 4 days prior to Steve showing the “new” data. If you want to see a before and after go here….. http://suyts.wordpress.com/2012/04/10/sea-level-rises-to-new-lows/
I didn’t overlay it like Steve did, but sometimes its easier to see. The ones I generated didn’t have any of the idiotic corrections in there including the seasonal adjustment so the sine waves are easier to see.
Anthony, you’re more than welcome if you wish to use them as well.
@ur momisugly TomRude
Yes, it is an intriging read. They are clearly obsessed with coming in line with Jason I , after they adjusted Jason. We also see Jason 2 has been quiet since Jan 25 and had it already shows some incredulous trending.
@ur momisugly John from CA…….
Yes, I still have all of the original data sets I downloaded from PSMSL on two separate PCs. I went back and check both.
Like Anthony, I usually attribute stuff like this to incompetence….. but this is too much. I think Steve is correct. This is done in preparation to the IPCC 5.
Let us hoist a toast to dear, departed Tuvalu. With all of this sea-level rise over the past few days, they have to be underwater now.
This manipulation, which has no other name,
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It does have another name. It’s called a correction.
Now imagine why they were not there in the older graphs, and how being there would create a trend probably very near to ZERO!
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Ahh. Well that’s the result we want do it must be the truth.
LazyTeenager says:
April 12, 2012 at 4:59 pm:
“It’s called a correction.”
Then explain why all corrections, whether sea level, temperature history, or current temperatures, seem to go in the most alarming direction.
LazyTeenager says:
April 12, 2012 at 4:59 pm
This manipulation, which has no other name,
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It does have another name. It’s called a correction.
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Who is authorised to make corrections?