Sea Level Graphs from UC and some perspectives

Just eight points I’d like to make.
1) Whether or not it is a problem depends very much on where you have built your bungalow, mansion or coastal road. My local council has been in an uproar for a few years now over whether a big real estate development should be allowed to go ahead given that the land is one to two metres above sea level. (Google “apollo bay development”). And there are an increasing number of such disputes appearing around Australia. The issue of maintaining and in future moving roads and other such infrastructure is a big one as it is a potentially huge burden on the rate payers of coastal councils.
2) It won’t be a simple matter of vertical rise in sea level.
* The rise will in many places cause all sorts of kick-on events in coastal processes. With the coastal development I mention above, a big concern is that a rise of half a metre will cause the loss of coastal sand dunes which shield the area where the development is proposed from storms.
* The loss of these dunes will mean that a major road may need to be rerouted away from the coast and through the area where the development is proposed, or will need to be built onto a causeway at great expense.
* The causeway will probably be necessary in any case because without the dune barrier storm surges onto the river flats on and around which the development is proposed is likely to be significantly increased.
* Furthermore the inundation of the estuary and river flats will mean that when floods occur, they will back up much higher than now.
* Because sea levels have been relatively constant for a few thousand years, dune systems have built up along many coasts. As the erosion kicks in, a small rise is likely to cause much bigger changes to inundation regimes than otherwise would be expected.
* Also, inundation in bays is constrained by the cross sectional area of their inlets. With many Bays a small increase in average tidal height will significantly increase the rate at which water can enter. This will translate into a significant magnification of tidal heights along some bay shores.
3) Sea level rise will not be uniform around the World due to prevailing winds, currents etc. Along some coasts the rise will be much higher than the average.
4) The productivity of many of our ocean fisheries is dependent on estuarine and near coastal ecosystems such as mangroves and saltmarshes. Because throughout much of the world land is inhabited and farmed right up to the current high tide mark, as sea levels rise, people will defend their land by building sea walls. Those ecosystems will therefore have nowhere to go and will diminish, thereby impacting on fisheries.
5) Many coastal regions are currently protected from storm surges by wetlands and marshes (think New Orleans). So the loss of such ecosystems in addition to rising sea levels will further exacerbate the impact of storm surges.
6) The rise won’t stop when we get to 2100.
7) Goodbye to your favourite beach.
8) I hope the trend is in fact linear. Because if it follows some of the newer projections that include glacial melt then the cost of adaptation in coastal cities is going to be astronomical and unrelenting. Heck, we saw recently that the wealthiest nation on earth couldn’t even keep one city safe. And that disaster was also predicted decades in advance. Good luck with Florida!

And another thing about alluvial rivers: (see my previous note 00:35:54) As the level of the water in the bay or gulf or sea rises the in-flowing river will begin to slow farther upstream. Such slowing causes the material carried by the water to settle. So a rising sea will produce more rapid land buildup. These processes are not linear. Look at “competence”, and “capacity” on this site: http://myweb.cwpost.liu.edu/vdivener/notes/streams_basic.htm
With the things I’ve mentioned going on and the sea level rise so small it doesn’t seem that much ought to be made of the issue.
Storm surges and seismic sea waves are way bigger worries and will remain so regardless of any climate change.

I prepared a post back in December that illustrated Sea Level data globally and for the big three oceans:
http://bobtisdale.blogspot.com/2008/12/sea-level-data-global-and-indian.html
Looking at the annualized data through 2007, the Pacific and Atlantic showed recent declines:
http://i33.tinypic.com/15pn3tj.jpg
http://i34.tinypic.com/m7b994.jpg
But the Indian Ocean was showing an accelerating rise through 2007:
http://i33.tinypic.com/9kpm39.jpg
That acceleration in the Indian Ocean came to an end in 2008:
http://i35.tinypic.com/xcomq0.jpg
I’ll update that series soon.

Yet another thing blown out of all proportion… and the backlash continues to grow.
On a radio station here in New Zealand specialising in Rock music, (Radio Hauraki, for those of you from round here), they have a series of ads asking you “your rcok gone soft?” The solution to this terrible malaise being to listen to said radio station. Their latest ad goes like this:
“Worried about the recession?
Concerned about global warming?
Your rock gone soft?
Notice a trend here? – HARDEN UP!”
I didn’t think commercial radio was capable of this anymore. Gave me a chuckle on the way to work.

One thing I find interesting is the way the “0” of the ΔMSL in the sea level graph from the University of Colorado keeps shifting. For example, the first TOPEX reading in 2004_rel3 is around -11mm, in 2006_rel3 the same reading is at 4mm, in 2007_rel2 it’s -30mm, in 2008_rel4 it’s -23mm, and in the 2009 graphs it’s hovering around the -26mm line. Do they recalculate every time? If the rate of change is only ~3mm/year, why does the MSL shift so radically (34mm between 2006 and 2007)?
I also noticed that the Jason readings aren’t static. For example, there are two “outliers” above the highest blue 2002 peak in the 2004_rel3 graph; the two squares are practically stacked in a column. In 2006_rel3, those outliers overlap; in 2007_rel2 they’re side by side (or something else moved up); in 2008_rel4, it’s another stack; then in the 2009 graphs, it’s a trio in an L formation. That doesn’t look like a change caused by compression of the graph. WUWT? I thought with satellite measurements, once it’s measured, it’s measured. Are 2002 readings adjusted/corrected as late as 2009?

6 metre sea level rise
This report on the Wilkins Ice Bridge has been running ABC News Australia for the last couple of days. I am sceptical because everytime there is a conference we have some dramatic event that coincides which supports global warming theories for
‘Ice shelf split due to ‘climate change’
Global warming no doubt contributed to the shattering of a major ice shelf in Antarctica , Environment Minister Peter Garrett says.
The ice bridge linking the Wilkins Ice Shelf and two islands snapped at the weekend.
‘I don’t think there is any doubt global warming is contributing to what we are seeing on the Wilkins Ice Shelf and also more generally in Antarctica ,’ Mr Garrett told ABC television from Washington on Monday.
The Scientific Committee on Antarctic Research (SCAR), comprised of peak scientific bodies from 23 countries, including Australia , will present modelling on global warming at a conference in the US on Monday night.
It has found ice loss has accelerated and the sea level could rise by as much as six metres by the end of the century.
Mr Garrett said he had not seen the SCAR report yet.
‘The fact is we are now entering a period where we are in a position to observe, particularly in the Antarctic, the consequences of global warming and climate change,’ he said.

I have a question about sea levels that I was hoping someone could answer.
I’ve heard numerous times that sea level rise has ‘accelerated’ since 1992. However, this appears to be the time when sea levels measurements largely shifted from tidal gauges to TOPEX/Jason.
My question is, what have the tidal gauges said about rising sea levels since 1992? Have sea levels been rising more quickly or is it the switch from two different measurement systems that gives the appearance of an acceleration? And lastly, if there is a discrepancy between the two measurement systems, how do scientists reconcile the two?
Thanks . . .

The Port of Auckland Mean Annual Sea Level graph seems to dance about like a fiddlers elbow… up and down… with some big changes over a small periods of time. This made me wonder how can anyone really be estimating a Global Sea Level figure with any real accuracy… measuring all point simultaneously and allowing for all the high and low tides… and what about the height of the waves… and what impact might plate tectonics have over a period of a 100 years… mmmm…. then i saw the graph caption: Seasonal Signals Removed… and i thought: Here we go again; data massaging…. Then i was thinking back:
How many times have i seen waves less than 30cm high?
So are these Sea Level graphs really accurate, factual or meaningful?????
Then I started Googling and found: http://www.mfe.govt.nz/publications/climate/coastal-hazards-climate-change-guidance-manual/html/page20.html
And this does seem to indicate that this science is really an art form…..
QUOTE
Longer-term fluctuations (lasting at least a month) in the mean level of the sea are important components when assessing inundation and erosion hazards. These fluctuations are typically related to:
1) The annual heating and cooling cycle caused by the influence of the sun on the ocean. Mean sea levels tend to be higher in late summer and autumn and, over a year, can fluctuate around ± 0.04 m on average, but up to ± 0.08 m in some years.
2) Interannual 2–4 year El Niño-Southern Oscillation (ENSO) cycles. Mean level of the sea is depressed during El Niño phases, and is higher during La Niña phases, with fluctuations of up to ± 0.12 m on both east and west coasts of the upper North Island. An analysis of the magnitude of fluctuations further south is currently underway.
3) Interdecadal 20–30 year Interdecadal Pacific Oscillation (IPO) cycles. The rate of sea-level rise tends to be higher during negative phases of IPO and tends to flatten out during the positive phases of IPO. The IPO facilitates sea-level fluctuations of up to ± 0.05 m. The IPO has been in a negative phase since about 1999.
UNQUOTE
So looking at your Auckland graph it looks like the HIGH WATER mark was reached in the late 1940s and that the curve then started on a downwards trend… and that seems to have a familiar ring to it somehow…
I know i really enjoy a massage…. but i do not extend this luxury to data…

Gerard (01:47:55) :

This report on the Wilkins Ice Bridge has been running ABC News Australia for the last couple of days. I am sceptical because everytime there is a conference we have some dramatic event that coincides which supports global warming theories for
‘Ice shelf split due to ‘climate change’

This is my view on the ice shelves breaking off.
It is my feeling that the ice shelves do not indicate current or recent conditions, but rather, an accumulation of various effects over time. During the LIA they were exposed to SST’s which were much cooler.
The record indicates that, from 1701 to 1761, surface temperatures were on average 1.4°C cooler than during the past 30 years. ( Source: http://cat.inist.fr/?aModele=afficheN&cpsidt=1132291 )
At other times the oceans in the area have been much warmer (Holocene Climate Maximum, Roman Warm Period, Medieval Warm Period, etc). Yes, some of the Ice lost has been tens of thousands of years old. However, 40,000 years ago their reach over the ocean was most likely much further. A lot has changed in the past 10,000 years, the warming into the Holocene. That warming and 10,000 years of the interglacial, 10,000 years of temps 8 degrees warmer than when they formed, 10,000 years of warmer seas beating on them is what the break-off’s reflect. A process which started long before fossil fuels.
To some extent, ice shelves are a poor climate indicator, they react to slowly. The story they tell is at times the same story that Glaciers which do not have a coastal edge tell. I did a brief blog on The Story of Glaciers not long ago.
http://penoflight.com/climatebuzz/?p=88
Having been attached and anchored the shelves will add to sea level, but, only the portion / volume of them that was previously above the water will be an addition.

re Gerard – the same story was published in our online newspaper. The article claimed unprecedented ice loss and whopping 3°C warming in Antarctic! It was fun to debunk that junk in following discussions by linking to the (increasing) southern ice anomaly and (decreasing) southern polar satellite temperature record. Another folks got their eyes open, I would say.

The fact is sea level are flatlining now since 2006 are may actually start to decline…..due to reduced watts/mt from the sun. There is also a hint that Co2 levels are starting to do same.. very speculative but there are signs…re Peter Garrett should stay with his music band (or really learn some meteorology or like) LOL

OT but this cooling (forecasts) seems to be worldwide and pretty obviously becoming more persistent and verifiable
http://wxmaps.org/pix/clim.html go to climate and check each continent Ie USA
http://wxmaps.org/pix/temp1.html ect…

DJ (01:33:42) :
3mm rise per year will lead to an average coastal recession of 3cm to 30cm per year for sandy beaches – that puts places like Florida in line for more than 100 feet of coastal recession this century with a low end sea level rise. This simple fact is captured in Brunn’s rule which is well known to scientists. Here’s some examples of what happens when sea level rise meets people…
Just wondering – do you happen to know of a period since the last ice age when sea levels weren’t rising.

Like Sid Brooks, due to the fineness of variability, I have zero confidence in this data. There are so many uncontrolled variables in this type of measurement as to make the conclusions worthless. Strikes me as more of a case of predicting what you expect rather than what there is. A lot of the methodology I read about, once you strip away all of the complex math and stats, seems to begin with the old saw we learned in early physics classes: “assume a frictionless surface…” Assuming net sum zero uncontrolled variables plus $10 might get you a Starbucks.

One thing that is’nt mentioned here is that local sea levels are largely dependend on Earth’s gravitational field. “Sea level” to us all means a flat surface over thousends of kilometers, but that’s far from true.
As shown in http://www-app2.gfz-potsdam.de/sec13/animated-potato-e-cms.html sea level differences are up to 200 m in “relatively close” areas as east of South Africa and south of India. 30 cm is nothing in comparison to that entirely natural factor.

Take a look at these:
http://klimakatastrophe.wordpress.com/
The three posts are about sealevel change. Teil 1, Teil 2 and Teil 3.
Even if you don’t understand the german language, the graphics can be understood:
http://klimakatastrophe.wordpress.com/2009/03/22/beschleunigt-sich-der-globale-meeresspiegelanstieg/
http://klimakatastrophe.wordpress.com/2009/03/27/beschleunigt-sich-der-globale-meeresspiegelanstieg-teil2/
http://klimakatastrophe.wordpress.com/2009/03/28/beschleunigt-sich-der-meeresspiegelanstieg-teil3/
Nothing extraordinary…. Im Westen nichts Neues ;-)))

Anthony,
Thank you for the article but the illustrations you have added to illustrate the flooding potential caused by sea level rise gives the article a somewhat alarmist impression. There is no reason for any alarm at all.
Why? Because the sedimentation process in accord with the tides will raise the land in the river delta area.
Speaking of Alarmist Propaganda at this moment in time:
The Wilkinson Ice Shelf is making the (political) news again, big media coverage (CNN) directly followed by a comment from Clinton that we finally understand how serious the Global Warming problem is and that we have to act now.
The skeptics now have to show what they are worth now and undertake a counter offensive.
They are seriously trying to put us all in Green Shackles.

In the 2004 graph, the 2003 peak is higher than the 2004 peak.
In the 2005 graph, the 2003 peak is higher than the 2004 peak.
In the 2006 graph, the 2003 peak is now a little lower than the 2004 peak.
In the 2007 graph, the 2003 peak is well below the 2004 peak.
In the 2008 graph, the 2003 peak went back to being higher than the 2004 peak.
In the 2009 graph, the 2003 peak once again became lower than the 2004 peak.
I thought they ‘measured’ this stuff. Did Babe Ruth now hit 64 Home Runs in 1927? Is data really allowed to change so much after the fact?

There appears to be a great difference between tide guage-measured and satellite altimeter-measured results. For example, Holgate (2007) estimated 2.03 mm/yr (1904-1953) and 1.45 mm/yr (1954-2003). Domingues et al. (2008) estimated ~ 1.5 mm/yr for the last 50 years, while Wunsch et al. (2007) estimated 1.6 mm/yr also for the last 50 years. Morner is even lower. Woppelmann et al. (2007) found that correcting for exact GPS position also reduced the rates.
We know that there is great regional variability (up to two orders of magnitude larger than the mean) from altimeter measurements (and tide-guage?), but I believe that this variability is greater with altimetry. Since altimeters are to some extent set to tide guage records, it probably depends on which ones they are standardised against.
Morner had a comment (don’t know where) that recent altimetry was set to a Hong Kong tide guage that showed an unusually high rate.
While we also know there is considerable lifting and sinking of land masses, how can we resolve the differences between these two methods, tide guage and altimetry?
Refs cited above are:
Domingues, C.M., Church, J.A., White, N.J., Gleckler, P.J., Wijffels, S.E., Barker, P.M. and Dunn, J.R. 2008. Improved estimates of upper-ocean warming and multi-decadal sea-level rise. Nature 453: 1090-1093.
Holgate, S.J. 2007. On the decadal rates of sea level change during the twentieth century. Geophysical Research Letters 34: 10.1029/2006GL028492.
Wunsch, C., Ponte, R.M. and Heimbach, P. 2007. Decadal trends in sea level patterns: 1993-2004. Journal of Climate 20: 5889-5911.
Woppelmann, G., Miguez, B.M., Bouin, M.-N. and Altamimi, Z. 2007. Geocentric sea-level trend estimates from GPS analyses at relevant tide gauges world-wide. Global and Planetary Change 57: 396-406.

Andrew P (01:52:43)
The converse is also true:
If the seal levels are falling, polar bears have less to eat.
Less food for polar bears = reduced population thereof.
Less seal levels = less polar bear levels
Less seal and polar bear levels = less mass.
Less mass = less displacement.
Andrew P = A Big “F”.
QED 🙂

Mike Bryant (00:52:24) :
I can’t quite figure it out, but there seems to be something rather odd about the evolution of the 2003 spike… Has it been lowered with respect to the 2004 spike? Are these adjustments more evidence of human caused sea level rise? I guess sometimes these graphs must be tortured into submission…
Sid Brooks Australia (01:41:02) :
Regarding satellite sea height measurements. I worry about the accuracy of the published data for the following reasons:
1/ I don’t believe that the parameters of the satellite orbit are known to within millimeters.
The altitude of the obits are affected by many things such as orbit decay, the position of the moon, diurnal effects from the sun, mass concentrations in the earths crust (masscons) etc.
I am on the same page. It is only yesterday or so that on the Lindzen thread we were told that the UV spectra had to be corrected because the satellites were losing height, or something like that. I wonder if this correction is in ? If they are losing height they will be measuring a smaller distance to the sea, taking it as rising waters? who knows. As this error favors the alarm I would suspect, like the surface station data, nobody will be correcting for it. It is erendipity that it goes the other way for UV?
Just heard on the greek radio an alarmist announcement: things are much worse than we thought, we will all drawn.
too m

“Craig Allen (01:02:02) : Because sea levels have been relatively constant for a few thousand years, dune systems have built up along many coasts. As the erosion kicks in, a small rise is likely to cause much bigger changes to inundation regimes than otherwise would be expected.”
Sea levels have been relatively constant? Could you show a source for that? Only sources I can find show some major increases in the past, and pretty much the same slow, steady gains that we see now for about the last 8K years or so.
http://en.wikipedia.org/wiki/File:Holocene_Sea_Level.png

DJ: Your second link leads to pictures of the Tuvalu Met Office. We’ve discussed Tuvalu Sea Level numerous times here at WUWT. There are multiple reasons why Tuvalu becomes inundated with sea water. I’m sure others will elaborate.
The following is a link to a graph of the Sea Level data for the coordinates of 8s by 179E (Tuvalu’s coordinates) from the University of Colorado Sea Level wizard. Link to Sea Level Wizard is here:
http://sealevel.colorado.edu/wizard.php
Tuvalu’s Sea Level graph is here:
http://i39.tinypic.com/219wcpy.jpg
Using the smoothed data as reference, Sea Level at Tuvalu rose a whopping 3.6 cm from Jan 2000 through the end of the data. Prior to that, the data is skewed by the 1997/98 El Nino, which caused the dip at that time. And before that, the data is impacted by the 1991 eruption of Mount Pinatubo.
And here’s a graph of the Byron Bay Sea Level (28S, 154E):
http://i42.tinypic.com/2zgfcds.jpg
Can’t get a much flatter trend line than that. There must be something else going on in Byron Bay.

Alan the Brit, John Hulquist re sedimentation of deltas.
I think there are not enough geologists on this site (although its not WUWT’s fault). The most significant blogs on this thread are the two above who have noted the well known phenomenon (to geologists anyway) that when sealevel rises, river deltas rise, too. With a sealevel rise, the river flow is slowed a bit upstream and it drops its sediments early, building up the delta to its original level. Indeed, the level of the delta is decided by the sealevel itself! During the last ice age, the Mississippi delta was 130 metres below what it is today. As the water rose, the delta kept pace with it and when sea level more or less stabilized, the delta grew outward into the gulf.
I haven’t seen any models of current conditions (people seem to be building only doomsday models these days) but the mechanism is so simple that a credible model would be easy to design knowing the river burden of sediment per year and volume of water average per year, and the delta area and profile below the sea level, one might show that with a 30cm sea level rise a century, the Ganges delta may actually continue to grow in areal extent above sea level. I would say, that this has happened already in the 20cm sea level rise since 1870 shown by the NZ tide guage.
This flooding of the Ganges Delta has figured so prominently in the AGW arsenal of disasters to come and is a fixture on BBC’s doomsday documentaries that gets trundled out every time there is something new to say, that I think WUWT should find a professor of geology to do a post on this item. When I graduated, my calculator was a slide rule so I’m not computer graphics savvy enough to make a contribution in the pretty form that it deserves. Anyway, this pesky drowning of the Bangladeshis has got to stop.

The observations of Dr Nils-Axel Mörner “The Greatest Lie Ever Told” casts serious doubt on these satellite measurements as well as other assertions of rising sea levels (unless the sea is rising and the land is rising, ie earth puffing up).

for Craig who is worried about road maintenance –
the entire US interstate system has been built since the 1940’s. What is that? The time required for sea level to rise 5 inches?
I am 64 years old and your warning that I would have to say goodbye to my “favorite beach” by 2100 terrifies me. If Venice, Italy is any proof of what people will do in response to such issues, I would have to believe that man can deal with worse.
I am an optimist, I see the situation in reverse. Obviously, sea level rise created the beaches we now have (it has been rising for a very long time). Why would that process stop?
I think that what is “astronomical” is the tendency to hyperventilate about something that few of us will ever see.

So we have three independent measures observing ocean decline in rate of warming:
Flattening in rise of temperature with direct measurements, sea-level rise by flattening of temperature-controlled thermal expansion, and flattening of rise of MLO measured atmospheric CO2 owing to Henry’s Law–temperature controlled partial pressure of CO2 in the oceans.
All confirming the tail is wagged by the dog and the tail cannot possibly alter its behavior.

This reminds me of another issue I have with “increase” graphs.
Here is CDIAC/BP’s graph of global fossil fuel CO2 emissions
Here is Mauna Loa’s graph of seasonally-adjusted CO2 rise, with the global fossil fuel CO2 emissions curve tucked in.
MLO’s emissions curve does not have the shape of the CDIAC/BP curve at all. It’s veeeeery smooth. Makes one wonder.

“It seems sea level has been rising for awhile, and that the observation line in black, if you follow the linear trend, will also end up somewhere between 20 and 30 cm by the year 2100.”
Except that the sea level rise trend before 1900 was less than the slr trend after 1900. Which is exactly opposite of what you expect from a “little ice age recovery” which should have the fastest response early on and then slow. Except that the whole point of AGW is that we _don’t_ expect the trend to just be linear if we keep pumping GHGs into the atmosphere. And the projections you show are the IPCC projections which specifically note that they don’t include any acceleration from greenland or Antarctic ice melt, which, while still not well understood, certainly seems unlikely at this point. So, if we’re _lucky_ SLR will be less than 30 cm in 2100. But if, heavens forbid, all the people on this site are wrong and we’re unlucky, we are looking at a meter of SLR, which won’t matter to people living in Colorado, but will matter a lot to people who are living near coasts, especially anywhere were there are already storm surge problems…

http://www.statesman.com/blogs/content/shared-gen/blogs/austin/weather/entries/2009/04/07/record_lows_thi.html
All time record low for Austin TX

IF the second quote from Dr. Mörner is correct, that sea level rise has not been more than “… 1.1 mm per year”, what has the real trend been since 2004?
Mike

Don’t see what the fuss is all about. How much has sea level risen in the last 200-500 years? Was there mass panic? No. if your feet get wet move.

In Singer’s book “Unstoppable (Every 1,500 Years) Global Warming”, in his chapter on rising sea levels he states that the most likely sea level rise this century will be about 10 -15 cm (4 – 6 inches), the same rate of increase as in recent centuries, and that melting at the poles is offset by increased humidity and snowfall, adding further ice.
INQUA’s (International Union for Quaternary Research) Commission on Sea Level Changes and Coastal Evolution forecast of “seal level” (yes, the typo is right there in the book) rise is “10 cm – plus or minus 10 cm”.
Alarmists LOVE to exaggerate predicted sea level rise, and consequent damage from that. Most coastal damage though, is from sheer stupidity. Of course, what they miss entirely is the fact that sea level rise, like warming is just about 100% natural.

Everybody save articles like this for future reference.
http://www.reuters.com/article/domesticNews/idUSTRE5363D320090407

If the continents move at 4cm/yr and the MSL is only increasing by 2mm/yr, why can’t this change in MSL be attributed to a change in sea basin geometry.

Dave,
Does that data also remove the “shifting zero” that Katherine brought up?
Just as an example, looking at 2006, its values are: 35, 33, 33, 26, 55. WUWT??? Like the temperature data, I would assume one should set a zero and stick to that standard in all subsequent runs, otherwise how can a time trend be detected.

One thing I could not help but notice is that 2006 R3 shows an increase of 45 mm, while all the other releases show 20-25 mm. From 2004 to 2008 the line is flattening at 20-25 mm. Clearly someone had some data problems there.
And one has to take into account the increased accuracy of the global measurements achievable by TOPEX/Poseidon and Jason. These two missions employed differential GPS that allowed accuracies of 10’s of CMs in surface measurements. Before that the error bars must have been in the meters range. If you look at the period for these two missions it is +/- 20 mm, well within the error bars for differential GPS from LOE considering the tidal situations you illustrated so well.
If one takes the limits of differential GPS from LOE into account, then the changes form 1960 to 2008 shown in the New Zealand graph could all be due to simply having better measurements – no appreciable increases may have occurred during this period.
Trying to say there are 20-25 mm’s difference in a measurement whose accuracy I doubt is below 10 cm’s seems to be a stretch.
FYI – I am doing this all from memory from my work at NASA reviewing applications of GPS to NASA programs from the mid 1990’s. If someone has actual references that would be interesting to see.
Cheers, AJStrata

OK, stopped being lazy and did a quick search and noticed that the TOPEX altitude can only be determined via differential GPS to 5-8 cm, which means the measurement of sea surface is probably in the 10 cm range. There is no statistical basis for +/- 25 mm shown in the chart. It would seem to me this is statistically zero rise in sea level.

Forgot the link: http://www.agu.org/pubs/crossref/1992…/91JB02562.shtml

“3mm rise per year will lead to an average coastal recession of 3cm to 30cm per year for sandy beaches – that puts places like Florida in line for more than 100 feet of coastal recession this century with a low end sea level rise.”
Maybe the sea levels will rise as high as they did during the last interglacial (I believe some 6 to 8 meters higher than they are now).

Aron (06:29:59) :
“Everybody save articles like this for future reference…”
Thanks, Aron, but…for sure this year even small tropical storms will receive a “name”, otherwise it would mean to say that the “King is naked”, nobody would dare to do that.

Comparing these nanometer sized increases with continents which are RISING up, chances are, that nature will not please Gwrs.
“The Arctic Ridge has the slowest rate (less than 2.5 cm/yr), and the East Pacific Rise near Easter Island, in the South Pacific about 3,400 km west of Chile, has the fastest rate (more than 15 cm/yr).”
http://pubs.usgs.gov/gip/dynamic/dynamic.pdf

And the trend of AGWers is to produce Hockey Sticks everywhere… Hah!
http://upload.wikimedia.org/wikipedia/commons/4/44/Phanerozoic_Sea_Level.png

The highest resolution measurements of ocean level at specific locations appears to be from using quartz resonant pressure sensors. See:
High Accuracy Pressure Instrumentation for Underwater Applications Mark H. Houston and Jerome M. Paros, ParoScientific
Highly Stable Long-Term Measurements of Height Differences with Digiquartz Depth Sensors, Dr. Theo Schaad, Paroscientific Inc. Technical Note G8072 Rev. A, 13 April 2006
Nano-Resolution Oceanic, Atmospheric, and Seismic Sensors With Parts-Per-Billion Resolution, Dr. Theo P. Schaad, Paroscientific, Inc. Technical Note
Doc. No. G8218 Rev. E, 10 March 2009
The long term “accuracy” is claimed to be about 100 ppm.
Can or have the satellites be calibrated against ocean patches with an array of such pressure sensors?

AJStrata,
Thanks for those eye-opening observations. Are the numbers for Jason similar?
Mike Bryant

I agree with Sid, Masonmart, and others, that IMHO, we know mean sea level to the degree of accuracy published is very unlikely. The same with temps. I see many graphs, extending back for 100 plus years, with an implied accuracy of .001 degrees. Seems unlikely to me. Like looking at stock charts with a microscope. UAH mid-troposphere temps. peaked in 4/1998 and bottomed in 1/2000. Neither extreme has been breached for many years now. ISTM that there can not be a “trend”, without a new high/low. fm

Marcus:
But if, heavens forbid, all the people on this site are wrong….
Please show me, Marcus, how enacting the draconian reductions in fossil fuel energy use “cure”, allegedly required to prevent the allegedly disasterous GW “disease” effects, will themselves not instead most certainly produce massive disasters of their own – ill effects of the “cure” which are rather easily envisioned but have intentionally not been included in the ipcc’s Climate Change/Science “scientific” analysis of Climate Change, just as the obvious benefits to GW regardless of cause have not been included, or at least not anywhere near to the extent that GW’s adverse effects have been projected and even rather obsessively and neurotically disasterized.
[The ipcc’s efforts in these matters sound more like a massive Panic Attack, its proposed cure to which looks mostly like Suicide.]
Face it, Marcus. The ipcc, enc., is simply not doing real Science.

Seems to me I see a hockey stick, where the rate of change goes to zero starting in 2005….
Hasn’t anyone taught these so called scientists what a “significant figure” means? The AGW crowd talk about 0.6 degree temp rise when the equipment isn’t calibrated to closer than +/- 2 degrees. A 3mm/year rise in sea level when the sea has tides… give me a break I very much doubt the ability to measure a dynamic land/sea area with this type of accuracy, especially with rebound, erosion and sedimentation. The land is a DYNAMIC system where land is eroded and lakes and seas get filled with sediment. Time to take GEO 101.

I would urge caution to the literal use of Bruun’s rule as some have suggested to determine beach loss as a result of increasing sea surface levels.
Any local projection of inundation must take into account geologic changes. New Jersey is a prime example where the land mass is sinking some 7 inches per century as the result of isostacy -glacial rebound. The City of London which is also routinely shown at risk has a very large component that is due to natural sinking of the land mass. Projections of sea rise that do not incorporate geological forces paint a very distorted picture.

Mike Bryant,
TJ Overton grabbed the right numbers above and they are equivalent – Jason is attempting to gain more accuracy, but physics has its limits.
As I suspected the precision of the satellites is not down to the level of the mythical changes, Statistically these satellites show no increase.

So I’ll bite,
Why is it that the data for earlier years (the red dots) keeps on changing even in 2009. Are these people just making up data as they go.
I gather from the graphs that the correct result is supposed to be a perfect straight line, so all those point deviations from the straight line are just random noise.
Looking at the green dots in the first graph, it seems that the best fit curve to the dots starts flattening around 2004 or earlier, and the flattening accelerates around 2006, so in a few years it would seem to be turning down if the flattening and the acceleration increases as the recent data shows.
And just what part of the earth’s oceans does this refer to, since the Arctic ocean has actually been falling at least for about the ten years ending mid 2006 (based on European satellite measurements.
So why then do all the distant future predictions show an ever accelerating upward trend.
Oh I forgot, these are future predictions from a computer video game, and not actual physical data.
What if all those dots; well I suppose they are really circles, turned out to be actual measured values; meaning that is what the sea level was when theat particular circle was measured. If those were actual meausred sea levels, what is the purpose of the wavy blue line which seems to ignorte most of the circles, and then what is the straight black line for since the circles are clearly not following that black line.
It would help if these “scientists” published a physical equation that says what the sea level should be.
After all Max Planck managed to publish an equation for the spectral emittance of a black body radiator, wherein all the parameters in the equation are known exactly in terms of a few fundamental constants of the whole universe, that are mostly known to about 8 significant digits. Come to think of it, Max didn’t even have a real black body radiator to take measurments from; yet everybody who has made one since has been able to confirm his theory to the ultimate limits of experimental measurement.
It seems to me that one of those achievements is science and the other is largely nonsense.
Scientists should refrain from draweing straight lines on what purports to be experimental data graphs, unless they also provide the theoretical equation that describes that straight line, and explains the physical phenomenon being graphed.
Yes I think the problem can be described largely by saying that Meteorology is a complex, and somewhat inexact science that rests on real physics and chemistry and suffers from a lack of information to close the gaps; while Climatology which seems to be the snootier of the two; is in about the samer category as Astrology and Economics; and isn’t based on any theoretical models of any planet that we know about.
When the climate models can be run backwards to produce the original data on which Hansen’s AlGorythm for GISStemp is based; then the promoters of that pseudo-science may start getting noticed.

” Taxes are higher. Energy is more expensive, and less reliable. Other problems we didn’t even expect have surfaced. At that point I look at that graph in 2012. I see no sea level rise in 8 years, and now I’m pissed. In my average guy brain, I finally, fully get how bad I’ve been swindled.”
And that, sir, is why these graphs must be continually homogenized, massaged and tortured for your pleasure.

Thats what I like about you, Anthony, you are on to the “level!”

Watching the record of sea level rise is about as exciting as watching grass grow.
Oh, wait. In a couple more weeks or so the grass will be more exciting and it’ll be time to pull the mower out of winter storage. With nearly an acre of grass to cover {and it’s not a riding mower – hey, exercise is exercise}, by the time the backyard is finished it’ll be time to start over in front.
As for sea level change, get over it. It’s been changing since the end of the ice age (the real one, not just the little one). Now, if sea levels start dropping, then that’ll be something to start being concerned about.

Kaboom (03:57:21) :
Andrew P (01:52:43)
The converse is also true:
If the seal levels are falling, polar bears have less to eat.
Less food for polar bears = reduced population thereof.
Less seal levels = less polar bear levels
Less seal and polar bear levels = less mass.
Less mass = less displacement.
Andrew P = A Big “F”.
QED 🙂
But if fewer seals = more fish
And more fish = more displacement
Or do you want to take this all the way down to phytoplankton? Methinks you take my first post too seriously.

ralph ellis (06:00:29) :
.
“What about this analysis, that argues against historic sea-level rises (last 100 years or so).
http://www.john-daly.com/ges/msl-rept.htm
Any flaws in what is argued here?”
The post glacial rebound (PGR) is very real. Its affects are most easily observed in the the Hudson’s Bay region where rebound averaged 1metre per hundred years:
http://encarta.msn.com/encyclopedia_461511036/Hudson_Bay_Lowlands.html
The aspect of PGR that makes determining historic changes in actual sea level more complicated than just trying to compensate for the rising of land in the northern hemisphere in particular, is the fact that the adjacent seabed is also rising and spilling water southward causing the water to rise relative to the land away from the northern lattitudes. Geologists have attempted to estimate the viscosity or plasticity of the mantle of the earth out of scientific interest but few, I would wager, would be comfortable in its application in calculating such small annual overall sea level changes when so many other determinants are at play.

Ok it works now! Here are the 3 parts :
http://klimakatastrophe.wordpress.com/2009/03/22/beschleunigt-sich-der-globale-meeresspiegelanstieg/
http://klimakatastrophe.wordpress.com/2009/03/27/beschleunigt-sich-der-globale-meeresspiegelanstieg-teil2/
http://klimakatastrophe.wordpress.com/2009/03/28/beschleunigt-sich-der-meeresspiegelanstieg-teil3/
It’s in german but the graphs can be understood … 😉
Best regards
Edouard

Ouhps, SORRY, I posted them twice …

An inconvenitent truth. The NOAA website has data from a tide station in Santa Barbara, CA. The data has time breaks in it. The most recent set of sea level measurements is clearly lower than the previous set.

Coral atolls (such as the Maldives) are amongst the lowest lying land areas in the world, so one would think they are particularly vulnerable to sea level increases. But they’re constantly replenished by ongoing coral growth at their peripheries. Indeed it is characteristic of atolls that they are effectively live-coral outlines of ancient islands that eroded away long ago. Darwin originally speculated that the coral limestone skeletal deposits were immensely deep, and it has since been demonstrated that some atolls are solid limestone extending down a kilometer or more. Atolls are inherently at present sea level because they can’t deposit limestone much above sea level, and erosion rapidly removes any exposed dead materials.
The fastest growing stony corals (the Acropora etc) grow at over 150mm per year and hence dominate atoll deposition. Even the phylogenetically older stony corals grow at over 50mm per year. 3mm per year could not possibly drown corals. Atolls would be safe at even 10X higher rates of sea level increase.
As well as growing in place, all coral organisms reproduce and propagate by releasing massive numbers of a motile spore-like form that can travel potentially great distances to establish new colonies. Even in the event of a dramatic one-time increase in sea levels, corals would survive by establishing new colonies anywhere they could find favorable conditions.
The same mechanism would be used by corals to survive any substantive global warming. Stony corals are currently confined to tropical waters because they’re temperature limited — 22C is about the minimum sustained cold they can endure. With higher temperatures they would rapidly establish new colonies in more temperate latitudes.
Given the .5C temperature increase measured during the last century, coral ranges must have already been extended some measurable amount, and indeed this is documented in the literature.
It’s perhaps unsurprising that coral’s ability to positively adapt to warming conditions goes unmentioned in popular accounts.

Smokey:
Congratulations!, you just found a most convenient Hockey Stick!

Mike asked, “Does that data also remove the “shifting zero” that Katherine brought up?”
I only downloaded the most recent data set…So the “shifting zero” isn’t an issue. I’m fairly certain that only the most recent data is available to be downloaded directly from the CU site.
I’ve been playing around with the correlating the CU sea level data to the UAH Lower Trop. Ocean and Land temperature data. The Lower Trop. Ocean temperature correlates very well with the CU Sea level data right up until mid-2004. At that point the temperature data starts to show a clear cooling trend; while sea level continued to rise (albeit more slowly)…Although the onset of oceanic cooling in 2003-2004 does seem to correlate to the flattening of the seal level rise. Now that the land temperatures are also cooling…I’ll bet that sea level starts to decline over the next 20 years.
The Jerejeeva reconstruction clearly shows a hiatus of sea level rise (if not an actual declining of sea level) from 1942-1978…Coincident with the last cold phase of the PDO/QDO. Those sea level data can be accessed through the Proudman Oceanographic Laboratory’s website.

In Edward Tellers autobiography he talks about the Egyptians, in the late 1950s, thinking about using nuclear weapons to blast a canal from the Meditteranean to the Qattara Depression which is in the Sahara desert close to Libya. The Qattara Depression is 17000 square miles of desert which, on average is 200 foot below sea level. They are now, apparently, intending to do the same thing using more conventional means and, using the effects of gravity, pass the water through turbines to generate electricity.
Filling the Qattara depression would take at a questimate 40 years and, back of envelope calculations suggest, would reduce mean sea level by 6-7mm in that time.
If you believe mean sea level is rising, and that itself is open to debate, maybe we should encourage the Egyptians to fill up the Qattara depression and make an inland sea in the Sahara.
An aside; how much sea level rise is accounted for by the massive cargo ships and supertankers we have built over the last century. They displace sea water don’t they? I’ll leave somebody else to do the maths. Enjoy.

DJ – the Brunn rule is out of date and absolutely crude – a 2-dimensional model established in the 50ties. Check out some later work “testing” the rule here:
Davidson-Arnott R.G.D. 2005. Conceptual model of the effects of sea level rise on sandy coasts. Journal of Coastal Research 21: 1166-1172.
or http://www.bioone.org/doi/full/10.2112/03-0051.1
so overall, coastal erosion/aggradation will always occur as not a single coastline can be described as “stable” – unless you have a rocky shoreline and then it appears relatively stable. Coastline are probably the most dynamic environments on our planet. If you check out reports on sandy coastlines over the last few decades, you will notice that there were periods when the same beach was building up material and a few years later the beach material vanished (natural causes).

>Why are humans so arrogant to think that they can just sit their asses down somewhere and expect the universe to move around them? Such idiots.. If the sea is getting too close to you move!
Squidly in one sentence you sum up all that is wrong with the sceptics.
The arrogance is that we can defy the laws of physics which have applied on this planet since the year dot. CO2 is a greenhouse gas which will warm the planet. In the past it has contributed to warming and large sea level rise and it will do so again in the future.
The second point shows a complete disregard to the human and property rights of others. The “science” of the “sceptics” is hoisted on society without any warranty offered to those who will suffer the consequences if it is wrong.
Finally, you resort to insulting others you have never met and whose circumstances you will never understand. The compensation for a lack of “science” is all too common among “sceptics”.
REPLY: Well gosh, two can play at that game. the constant anger, the regular denigration of others skills and comprehension, and the hiding behind anonymity when hurling such attacks is all too common for “alarmists”, such as yourself. It’s fair dinkum when we look at your 95 comments here. – Anthony

Andrew P (10:17:54) :
“And more fish = more displacement
Or do you want to take this all the way down to phytoplankton? Methinks you take my first post too seriously.”
But Andrew, look at how serious this all is!
Because of the highly learned discussion between you and Kaboom, I predict that our esteemed leaders Harry Reid and Nancy Pelosi will declare the debate over, and no time to lose! “It’s obvious, scientifically, that more fish swimming will cause the water to warm rapidly, due to mechanical effects of their little tails waving back and forth,” I believe they’ll say. “Warmer water will mean even more rapid ocean level rises.” Then, they will propose doubling American tax rates to fund a new ocean going form of traffic police, to force fish to swim slower, thus wasting less energy, and keeping the oceans cooler. This force will require a large bureaucracy, which will be headed by whichever of their relatives aren’t currently under indictment for influence-peddling.
And they haven’t even begun to tax us for your “phytoplankton” observations yet.
Henry 😉
(/sarc off)

Thought it was interesting how much alike the charts above and the charts here of the dow futures are looking.
http://www.tradeinwaves.com/minidow.jpg

A mention was made of finger nail growth rate (13 angstroms/sec) for sea level rise,funny I remember finger nail growth rate is rate that Australia is moving towards Indonesia,quite fast for continental drift.

DJ warns:
The “science” of the “sceptics” is hoisted on society without any warranty offered to those who will suffer the consequences if it is wrong.
DJ, where is the science and warranty which shows that the consequences to “those who will suffer” as a result of instituting the alleged “cure” to the alleged “disease” of GW will not be worse than the alleged disease?
Conveniently and intentionally, the ipcc did not do this particular science, which would involve a thorough analysis both of the “costs” of the cure and the benefits of GW, regardless of the cause.
DJ, can’t even such a concerned individual as yourself at least wonder somewhat sceptically “why not” ?

@ Alan the Brit (00:08:42) and John F. Hultquist (00:35:54) sedimentation rates and deltas.
First, the channel of the delta will migrate over time. As the river empties into the ocean (or lake, or another body of water depending on the river), sediments are deposited. Over time, these sediments build up and the channel changes course (water flows down hill). So some parts of a delta are active, while others are not. Here is an image I found in a quick google search.
http://www.uwgb.edu/DutchS/graphic0/geomorph/missdlt.gif
Not the best image, but illustrates the point. Now there are a couple of things that happen when you are no longer adding sediments. First, river sediment tends to have a LOT of organic matter. That organic matter is quick to break down and this leads to subsidence. Moreover, sediment sitting on more sediment leads to compaction and dewatering and this leads to more subsidence, so parts of the river delta are slowly sinking.
Additionally, because of the sediment load on the crust, isostatic adjustment occurs which causes the crust in that area to subside.
So Alan, while there is the addition of land mass, its not as substantial as one would first think.
And John, the addition of sediment will not “raise sea level” because subsidence and sedimentation are happening at almost equal rates.
Gary Pearse (04:53:32) :
“I think there are not enough geologists on this site (although its not WUWT’s fault). ”
Hi there.
Ben

J. Peden (20:46:40) :
DJ warns:
The “science” of the “sceptics” is hoisted on society without any warranty offered to those who will suffer the consequences if it is wrong.
DJ, where is the science and warranty which shows that the consequences to “those who will suffer” as a result of instituting the alleged “cure” to the alleged “disease” of GW will not be worse than the alleged disease?
Conveniently and intentionally, the ipcc did not do this particular science, which would involve a thorough analysis both of the “costs” of the cure and the benefits of GW, regardless of the cause.
DJ, can’t even such a concerned individual as yourself at least wonder somewhat sceptically “why not” ?
The basis of my professional work is cost benefit analysis. I have little doubt that there is “no room, nor desire” at the IPCC for a competant and objective analysis of the cost benefit of the current proposed “Cures” for “AGW”.
Such an analysis would quickly show that the CURE (CAP & TRADE, De-Industrialisation) is the nothing short of Disasterous.

Smokey (11:23:49) : Craig Allen (01:02:02):”Because sea levels have been relatively constant for a few thousand years…”
Wrong as usual, Craig. And since that particular statement is the crux of your argument, your argument fails: click… click… the AGW/CO2 hypothesis is falsified: click [chart by Bill Illis].
I love seeing Smokey’s ripostes, again and again pretty spot-on to the particular warmist argument – and though warmists often say our arguments are the same, tired, old, long-ago-refuted arguments, IMO the reverse is a lot truer. There are a number of well-identified warmist tactics and arguments.
I’d love to see a collection of context-sensitive ripostes, perhaps done as an FAQ, perhaps a wiki format for skeptics to collaborate in? Or perhaps Smokey can do a post here, and Smokey, or myself, or someone, can gather up all the responses into an FAQ-type resource.
This is another variant of my visions for a skeptics’ wiki. This could be a way to start the ball rolling for a wiki – or not – it doesn’t matter because an “FAQ” would work in its own right. Just my thoughts.

because the ice that melted was RESTING IN WATER ALREADY..
Time to reframe your calculations and give back the “Best Science Blog of 2008″ award
None of us thought of that, Anthony, did we? Better pack up that award now.. 🙂

Not all coastal erosion is due to sea level rise. These houses were several fields away from the edge when they were built, but this bit of the Isle of Wight has been crumbling away for some time, taking houses, roads, hotels, a naturist camp and bits of a local theme park with it.
We lose about 10 feet a year, on average, but it tends to fall away in chunks after heavy rainfall has penetrated down to a layer of Gault clay, known locally (and aptly) as ‘blue slipper’. Geology 1, AGW 0.
http://farm4.static.flickr.com/3363/3423839400_37e8c53d93_o.jpg

“Ken Gregory (21:03:59) :
Satellite altimetry Topex/Poseidon/Jason data is ADJUSTED by the University of Colorado for NASA to match the rate of sea level rise measured by a set of 64 tide gauges. Any difference between the raw satellite measurement and the tide gauge measurement is ASSUMED to be the sum of satellite measurement drift error and the vertical land movement at the tide gauge location. A separate ESTIMATE of vertical land movement is made to determine the altimetric drift. This measurement drift as determined by the set of tide gauges is applied to the raw satellite data to create the adjusted satellite data.”

If I put icecubes in a glass and they melt, the glass doesnt run over, but if I throw a rock in there it will over flow. Could some of the rise in sea level in some areas be due to ‘island building’ undersea? How much does that new material displace water? I hear that volcano near Tonga is building a new island.
http://www.reflector.com/news/world/strong-quake-near-tonga-prompts-tsunami-warning-498835.html
Its done it before….
http://earthobservatory.nasa.gov/IOTD/view.php?id=7126
So while were worrying about melting ice raising our water levels, has anyone considered how much water must be displaced by a volcano that rises from the ocean floor to the surface? Tonga, Hawaii, Im sure there are others..

” Jared (03:48:08) wrote:
In the 2004 graph, the 2003 peak is higher than the 2004 peak.
In the 2005 graph, the 2003 peak is higher than the 2004 peak.
In the 2006 graph, the 2003 peak is now a little lower than the 2004 peak.
In the 2007 graph, the 2003 peak is well below the 2004 peak.
In the 2008 graph, the 2003 peak went back to being higher than the 2004 peak.
In the 2009 graph, the 2003 peak once again became lower than the 2004 peak.”
There are actually 3 graphs. Not just the 2003 peak changes, every peak and valley is different. Even the loose points hovering around the 60-day smoothing line are different. This is obvious when you look at the shape of the 1998 peak and the loose points above it.
2004: graph a – the 1998 peak is sharp
2005: graph a
2006: graph b – 1998 not so sharp anymore
2007: graph c – 1998 not sharp at all
2008: graph a again(!) – 1998 is sharp again
2009-1: graph c is back
2009-2: graph c
-This graph has been completely redesigned\recalculated twice – once in 2006 and again in 2007. Does anyone know how that has been done?
-It is peculiar that graph a comes back in 2008. What could be the reason?
Anthony, thank you for this great blog, on which I have been spending way to much time. It’s very good for my serenity of mind though.

Chuck near Houston (12:40:24) said:
“I’m surprised than no one (especially those of you with a geology background) has raised this issue of subsidence here.”
Chuck you may have missed my post at (21:18:59).
More than just subsidence due to sediment loading, is isostatic adjustment of oceanic crust as it cools down. Cooler things are more dense, and as oceanic crust cools and moves away from the spreading axis, it cools down, becomes more dense and “sinks” lower in the mantle.
So we have some crust sinking due to sediment loading, other sinking because of isostasy, and some crust (continental) rising due to isostatic rebound that has been occurring since the glaciers melt.
The whole deal makes for an interesting mess when trying to measure rates of change with respect to sea level.

Ken Gregory,
OK, I have to ask – what satellite measurement drift? As far as I know there is none, and it would not be linear. There is no drift in the position or timing (GPS based with RF link radiometric measurements used to provide independent tracking).
I would have to look at the payload designs again but there is no ‘drift’ in their performance.
Will check your link but that sounds like a lot of CU BS to me.
AJStrata

In my last post I of course meant to “below -50ºF“. Sorry to misquote you Smoky.

“Bill Illis (16:23:48) wrote:
I think some of the changes in the graph are the result of an error which was discovered last Summer in the processing algorithms for Jason-1 sea level when they were calibrating the new Jason-2 satellite.
This reduced Jason-1 ’s sea level trend from 3.3 mms per year to 2.4 mms per year and the old years were restated.”
Bill, the first recalculate graph appears in 2006, the next one in 2007.
So that can’t be what you mention.
I see no obvious differences in the 2008 and 2009 graphs, just 2 measurements in 2002 that have been retroactively corrected.
I’d love to see the corrected graph. If the trend goes down from 3.3 to 2.4 mm/year, that must might the sea level has been decreasing a bit.

Craig Allen offers an interesting question:

Here’s a puzzle. If, as you suggest, the predicted warming can not possibly cause significant melting of our ice-caps. How is it that the ice-cap covering a very substantial portion of North America during the last ice age to a depth of several kilometres, melted away with a global increase in average temperature of just 7 or so degrees?

Are you suggesting that we are facing a further 7 or so degrees rise in average global temperatures because of human produced CO2? If so, over what time frame?
If not, what temperature rise are you suggesting will occur because of human produced CO2 and over what timeframe, and what sea-level rise will that cause? What other effects will it have? Please be explicit.
Further, what will it cost to mitigate those problems by reducing CO2 production? What probability do you place on the proposed mitigation actually doing anything usefull? What cost do you place on mitigating the problems using other approaches, like moving people?

Richard Sharpe:
Reread my post. I clearly did not say that we are facing “7 or so degrees rise in average global temperatures because of human produced CO2”.
I’m not sure about the latest models, but the IPCC’s AR4 report [beware that’s a big pdf file) concluded that climate scientists believe that if we let greenhouse gasses rise to 1000ppm (in CO2 equivalents) we would face somewhere between 3.5 and 8 degrees rise by the time the climate equilibrium was reached. I hope humanity isn’t that suicidal. They concluded that if we continue on a business as usual emissions scenario we are likely to get between 2.3 and 4.8ºC warming between 2000 and 2100 with 3ºC being the most likely.
Smokey:

“And as always, it must be kept in mind that the current sea level rise is the result of natural climate variability. The theory of natural climate variability has never been falsified. And unless natural climate variability is falsified, the AGW/CO2 hypothesis fails.”

Mate, a straw-man doesn’t compensate for a logically flawed statement. The climate is naturally variable. No one has ever disputed that. We are taking a variable system and forcing it toward a state it is very unlikely to have otherwise have reached and at a far faster rate than is otherwise plausible.
Gary Gulrud,
The various economic analyses I’ve seen suggest that reducing CO2 emissions significantly will have a modest affect on the growth rate of economies, and may even boost them. It’ll certainly be a lot cheaper than wars and unrestrained financial scullduggery. The costs (in both financial and human suffering terms) of adapting to the predicted consequences of our current emissions path are otherwise going to be unimaginably huge.

Below is a link to a live presentation on sea level rise preparation and consequences in California. This was presented on April 9, 2009 at the California Coastal Commission hearing in Oxnard, CA.
Scroll down to Item 3, and click on the film reel icon next to Sea Level Rise Workshop.
http://www.cal-span.org/cgi-bin/archive.php?owner=CCC&date=2009-04-09