What's delaying UC sea level data from being updated?

The University of Colorado at Boulder releases satellite based altimetry of sea level change several times a year. This graph below is dated December 15th according to the image timestamp.

http://sealevel.colorado.edu/current/sl_noib_global.jpg

If the previous schedule is any indication, they are now almost two months overdue. I’m not implying any nefarious motives whatsoever, but I’m wondering why it is overdue. Below is the update list. Sometimes a nudge helps. So let’s call this article a friendly nudge. I sent a query from their web page asking why, and hope to hear back soon.

Changes to each release since 2006 Release 3

2007 Release 1 (10/23/2007)

Uses the new TMR replacement product version 1.0 for T/P.

Uses GDR-B for all Jason-1 cycles.

Uses Don Chambers SSB model for T/P and the default SSB model for Jason-1 GDR-B.

Correctly applies the off-nadir pointing editing criteria of Jason-1 GDR handbook.

2007 Release 2 (12/03/2007)

T/P cycles 8 through 16 are computed by correctly applying the new TMR correction.

The one-cycle-off time tag shift error is fixed.

2008 Release 1 (01/16/2008)

Corrects an error in the non-IB GMSL that mainly affected the annual variation.

Resulted from using an IB-corrected MSS reference. The error is corrected by estimating

a local mean sea level from the non-IB data.

2008 Release 2 (05/29/2008)

Applies an ad hoc JMR correction for Jason-1 GDR-B cycles 1 through 227.

Applies 1.6 mm correction for the IB error for Jason-1 GDR-B cycles 94 through 142.

2008 Release 3 (09/08/2008)

For Jason-1, a bug is fixed to correctly interpolate the mean sea surface.

Jason-1 GDR Version B cycles 1 through 232 are used.

2008 Release 4 (12/11/2008)

Uses GDR-C for cycles 180, 184, 186-190, 193-194, 196-240, 244-246, and 248.

Updates GDR-B with GDR-C standards, e.g., GDR-C JMR, range correction, SSB model,

etc.

2009 Release 1 (02/13/2009)

Uses GDR-C for cycles 11, 14-16, 151, 153-157, 159, 161-164, 166-167, 171-173, 177,

180, 182, 184-190, 193-242, and 244-256.

2009 Release 2 (03/12/2009)

Fixes a bug in the implementation of 1.6 mm correction for the IB error for Jason-1

GDR-B cycles 94 through 142.

Updates with GDR-C cycles are 3-6, 9-10, 12, 21, 133-135, 138, 143-145, 158, 165,

169-170, 174, 176, and 257.

2009 Release 3 (07/17/2009)

Updates with more GDR-C cycles. Added Jason-2/OSTM GDR cycles 1-28.

2009 Release 4 (09/18/2009)

Newly added GDR-C cycles are 13, 17, 19, 25, 47, 53, 56, 65, 118, 123, 142, 148-150, 168,

and 183. Added Jason-2/OSTM GDR cycles 29-34.

2009 Release 5 (12/04/2009)

Includes all GDR-C cycles except 69, 82, 137, 139, 178-179, and 243.

Added Jason-2/OSTM GDR cycles 35-43.

2010 Release 1 (02/10/2010)

Now includes all GDR-C cycles. Added Jason-2/OSTM GDR cycles 44-50.

2010 Release 2 (05/06/2010)

Added Jason-2/OSTM GDR cycles 51-61.

2010 Release 3 (07/26/2010)

Added Jason-2/OSTM GDR cycles 62-66.

2010 Release 4 (10/06/2010)

Added Jason-2/OSTM GDR cycles 67-77.

2010 Release 5 (12/15/2010)

Added Jason-2/OSTM GDR cycles 78-82.

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Jack Simmons
April 7, 2011 1:40 am

I sent an email to the folks up at CU asking when the website would be updated. This was on Feb 22, 2011. I received the following reply on Feb 23, 2011:

Jack,
Thanks for your inquiry about the Sea Level Change Research web site
(http://sealevel.colorado.edu). I work with Professor Nerem at CU, and
he forwarded to me your message. Almost all of the 2010 data are
already on the site, but 2011 data will begin to be added after the
data are released by NASA/CNES. We have been updating the sea level
data approximately bimonthly (every two months). The altimeter data
are released by NASA/CNES as a 10-day group of files corresponding to
the satellite track repeat cycle (10 days). There is also a two-month
delay between the time the data are collected on the satellite to
their final product generation (known as a final geophysical data
record (GDR)). We use these final GDR products in the global mean sea
level estimates. If possible, we are planning to shorten the time
between our global mean sea level updates.
We are currently reworking the web site, and a new feature will be RSS
and email subscriptions to our updates. I will send an email to you
when these features are ready.

Alcheson
April 7, 2011 1:53 am

It simply amazing… the last UC graph from 2010 (seasonal signals removed) gives a 3.0mm per year rise since 1993. The UC data that was shown at http://ibis.grdl.noaa.gov/SAT/SeaLevelRise/slr/slr_sla_gbl_free_txj1j2_90.png which includes the 2011 sea level data results in a rise of 2.9mm per year since 1993 (seasonal signals removed).
The data now shown at UC shows an average rise of 3.2mm per year since 1993 (seasonal signals removed), suggesting that there has been a huge increase in sea level rise in the past 6 months which is clearly not the case. What is wrong with this picture?

poitsplace
April 7, 2011 1:55 am

Ummm….why does the chart imply that the temperatures TODAY are still being just as suppressed by the “nuclear winter” and need correcting?

poitsplace
April 7, 2011 1:57 am

oops, wrong browser tab 😀

jones
April 7, 2011 2:05 am

OF COURSE it’s due to AGW…..
It’s so warm it’s evaporated………
Prove me wrong….go on…dares yer…

Cold Lynx
April 7, 2011 2:08 am

Why expect a steady sea level?
Is there ANY skilled geologist that would even think of stable sea level in a world with tectonic plate movements?
Is there a measurement of land level change made?
I bet that one would be showing much larger changes.

Frank White
April 7, 2011 2:19 am

“…when I started mooring a boat here in the Mediterranean sea,…”
The Med is clearly connected to the world ocean, but has not got much in the way of tides, which would seem to help to even out sea level on a daily basis and make altimeter readings more uniform. However, the seasonal difference would still be problematic. The level of the Med is lower than the world ocean in summer because of high evaporation. I am not certain, but I would guess that the level of the Med is higher in winter because of inflow from rivers and evaporation that is lower than in summer.
So data from the Med would need to be smoothed in a different way from oceanic data.

Frank White
April 7, 2011 2:59 am

Interesting the rate is about double the 1.5 mm/year estimated by Domingues and others in their 2008 paper in Nature, (http://www.cmar.csiro.au/sealevel/downloads/R733_nature07080.pdf)
The authors used a longer time-frame.

Taniwha
April 7, 2011 3:04 am

How do you measure sea level using satellites?

Very accurately. It is a really good way to measure sea level.

John Peter
April 7, 2011 3:05 am

“Jørgen F. says:
April 6, 2011 at 11:35 pm
In Denmark DMI has never been able to measure the changes to global sea levels. At the same time Denmark’s underground is not very active – however still adjusting after the last ice age.
http://www.dmi.dk/dmi/index/klima/klimaet_indtil_nu/vind_og_vandstand_i_danmark.htm
Graph in the bottom of the page.”
I guess Jørgen F means that DMI have not observed any change to sea levels around Denmark as the graph shows. This confirms my suspicion that the sea levels have not changed. Every time I go back to my Danish home town I have seen no change to sea levels in 60 years.

April 7, 2011 3:38 am

Geoff Sharp says:
April 6, 2011 at 10:08 pm
Do any other institutions monitor sea levels, or perhaps we can get the raw data and plot ourselves.

The French seem to be a bit more up to date. AVISO (Archivage, Validation et Interprétation des données des Satellites Océanographiques) is a joint project of CNES (Centre National d’Études Spatiales – French equivalent of NASA) and CLS (Collecte Localisation Satellites). They have data up to 2011.038337 (January 14, 2011) while the University of Colorado at Boulder Sea level change site only has it up to 2010.7415 (September 28, 2010).
The two datasets are not directly comparable as they use different adjustments and these are poorly documented at both sites.

andymc
April 7, 2011 3:40 am

The delay may have something to do with the Bangkok summit. Most of the attendees are bleating on about sea level rises. No so relevant if the sea level is, ahem, falling.

April 7, 2011 3:41 am

@Cassandra King
One would think that falling sea level would be the death of CAGW, but we thought that about colder winters, recovering sea ice, no tropospheric hotspot, etc.
Now it will be “global warming will leave the world’s shipping ports high and dry as the oceans evaporate and destroy the global economy.” Or something.
It will always be something. Too many powerful people have too much money invested in this hoax for it to go away.

Jer0me
April 7, 2011 3:43 am

One graph has the inverse barometer applied (at least it does not say not), and has ‘seasonal signals’ removed.
Here’s one without that ‘trick’:
http://crozon.colorado.edu/content/current-global-mean-sea-level-trend-seasonal-signals-remaining
For the life of me, I cannot get 3.1 or the new (higher even though it’s still going down?) value of 3.2 mm / year. Eyeball and calculator give me 2.8 or 2.9, even on the black line. Actual data points from start to finish give me 2.6 mm / year.

DMC
April 7, 2011 3:52 am

I’m 95% certain that the missing sea water is currently “in the pipeline” in the deep ocean trenches.
I’m 4% sure that since the CO2 level is going up, the atmosphere is denser and is pushing the sea-level back down.
I’m 1% certain that I am 99% likely to be wrong.

Joe Lalonde
April 7, 2011 3:54 am

Anthony,
When the evaporation machine is in full bore(like this winter) a great deal of water is picked up into the atmosphere.
Almost ALL of the northern hemisphere land mass was under cloud cover.

Frank White
April 7, 2011 3:56 am

What have a few decades worth of sea level data got to do with anything?
PK Banerjee,reported greater than 1,000 mm fall in sea level during the Little Ice Age (Marine Geology, Volume 167, Issues 3-4, 15 July 2000).
He considered this minor! Should we not expect sea level to rebound by at least 1,000 mm in 300 years? Should we consider this a minor rise? Why not?
Why should sea level remain at a point convenient for people who want to locate cities near the sea coasts?
From the abstract, “…. The Holocene highstand reached nearly 3 m above LTL at 7.3 ka, remained stable for approximately 1.7 kyr and was followed by a relative sea level fall. Between 5.2 and 4.2 ka, there was a second pulse of relative sea level rise of a few metres leading to a fresh spurt in coral growth along the northern coast of Mandapam and Rameswaram [east coast of India]. This was nearly contemporaneous with fresh melting of ice sheets of Antarctica. The Little Ice Age (LIA) witnessed a minor (>1 m) relative sea level fall along this coast, resulting in rapid diagenetic hardening and infiltration of goethite into the emerged foreshore sand at Karikovil and its neighbourhood. This was followed by a rise of the sea level during the last few centuries.”
For non-scientists, the Holocene is roughly the last 10,000 years. Sea level has risen about 120-140 metres (450 feet), mainly from glacier meltwater entering the world ocean but also from thermal expansion of water.

Philip Thomas
April 7, 2011 4:42 am

Maybe, if the sea goes the wrong way, so does their funding:(

DavidS
April 7, 2011 4:42 am

Delighted you have asked the question Anthony, however I won’t hold my breath.

Randy Links
April 7, 2011 4:43 am

My HADCRAP computer model indicates a sea level decline is to be expected as a result of over-fishing and the Gorian decline in polar bear numbers due to global warming. The decline of the polar bear has a twofold effect: less direct displacement of sea water due to declining numbers of polar bears in the water; and less indirect displacement due to less weight on floating sea ice.

Espen
April 7, 2011 5:09 am

Frank White: If the estimate of ~1 meter sea level drop during the LIA is correct, one really has to wonder what all the fuss is about – we’ve only regained 20-30 % of that so far! And even with 3mm/year, we’ll need another 250 years for the remaining, i.e. a total of about 550 years of rising sea levels – that’s probably a longer timeframe than the preceding period of dropping sea levels, i.e. a slower rate.

Bill Illis
April 7, 2011 5:10 am

Aviso was put in charge in calibrating the new Jason2 satellite and, subsequent to that being completed, they have continued to be one of the main operators of the data and the satellites.
All of the maps, time series and data into January 2011 can be found here. They have also included data from the European satellite – Envisat – which is recording sea level rise of only 1.2 mm/yr (and a decline of 1.0 mm in 2010).
http://www.aviso.oceanobs.com/en/news/ocean-indicators/mean-sea-level/products-images/index.html

Brian H
April 7, 2011 5:16 am

The water must be going SOMEWHERE! The warming is probably evaporating it, so that it’s now lurking somewhere in the atmosphere waiting to dump floods of water and excessive snow which will then melt and cause even more floods.
There! All fiddled fixed!

April 7, 2011 5:21 am
Batheswithwhales
April 7, 2011 5:21 am

Now this is interesting: they took the most recent graph down again! Gone…
Perhaps they realized they were a bit heavy handed with the adjustments this time…