Sea Level Graphs from UC and some perspectives

I got a couple of emails today saying that I should take a look at the most recently posted sea level graph from the University of Colorado shown below:

uc_seallevel_2009r2

The reason for the interest is that it dropped the rate of change from 3.3 mm/yr to 3.2 mm/yr. as shown in the next graph. That’s hardly news, since it is well within the error band of +/- 0.4 mm/yr.

uc_seallevel_2009r1

But I thought it might be interesting to go back and see what I could find in the UC sea level archive of graphs. I’ve presented all of the ones I’ve found below. I should note that in some years, UC may only release 2 graphs (as indicated by the release #) or up to 5 in one year like they did in 2005. For the sake of presentation simplicity, I’m only presenting the last graph to be released in any year.

uc_seallevel_2008r4

uc_seallevel_2007r2-1

uc_seallevel_2006r3

uc_seallevel_2005r5

uc_seallevel_2004r3

I realize there has been a great deal of interest in the flattening of the 60 day smoothing line that started in 2007 and continues to the present. But the trend line will take awhile to reflect any appreciable change in the rate if it continues to flatten. The yearly rate of rise has been between 3.0 and 3.5 mm per year since 2004.

Many projections by various models predict the rise of sea level:

Note the trend of the observations line from 1950 to 2000, if you follow the linear trend, it will end up somewhere between 20 and 30 cm by the year 2100. The graph above is from Wikipedia’s “global warming art” which for some reason doesn’t show the observations back that far.

Here is a better graph, from New Zealand’s Ministry of the Environment, which shows more of the historical record, all the way back to 1870:

sea-level-observed-plus-models

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.

To put it all in perspective, some example images are useful.

Here is what 3 millmeters of sea level rise in 1 year looks like. This is a tiny fuel cell chip, just 3mm x 3mm in size:

3mm-fuel-cell-ross-eng

3mm square chip - approximately the sea level rise in one year

I know that many people are concerned about sea level rise over the next century. In the rate of 3 mm per year continues, we’d be at 300 mm (30 centimeters) of rise in 100 years. Here is what 30.48 cm (12 inches) looks like:

wood_ruler

30.48 cm = 12 inches, the expected sea level rise in 1 century if the 3mm/yr trend holds

And  finally, here is what the tide gauge at Anchorage Alaska looks like:

Historical Anchorage Tide Gauge at extreme high and low tide

Historical Tide Gauge at Anchorage, Alaska - photo NOAA

Anchorage Alaska boasts the world’s second highest tides: varying over 40 feet (1219 cm), low to high tide. Ok, that is an extreme example, how about this one in France:

Mt. St. Michel on the north coast of France at low tide (left) and high tide (right).

The water surrounding this island is the Gulf of Sant-Malo.

Low tide

High tide

The point I’m making is that in 100 years, for some places that extra foot won’t make much of a difference. Some low lying areas will be affected certainly, but even some of the lowest lying areas of the earth won’t see all that much impact from a third of a meter of sea level rise in 100 years. Probably the worst place to live is in a river delta which is almost at sea level anyway. Even so, 30 cm falls short of the lowest notch on this graph of 1 meter.

Bangladesh is another low lying river delta where it is not desirable to live, yet many do. Even so it appears much of it is 1 meter or more above sea level.

Florida is often talked about as being at risk. yes there are a few places there that might be touched by a 30 cm rise in sea level 100 years from now.

Looking at the whole world, at the rate we are going, I’d say it will take awhile.

click for a very large image

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crosspatch

What I would like to see is a graph of trend since January 2006.

Alan the Brit

I believe our fingernails grow more than this rate per annum.
As for river delta, would there not be a corresponding build up of silts & sands over the same period adding to the land mass around the delta? The problems for river delta tend to be from sudden & dramatic tidal surges & or thro’ storms effects. Form the map supplied very little land will be susceptible to sea-level rises.
OT, why did Gorey Al not use the opening title sequence for Kevin Costner’s Waterworld movie, where it showed all the land dissappearing under water. Much more melodramatic I think.

John F. Hultquist

Second line “seal” >> sea
No need to post this on this thread – I don’t know how to get it to you any other way. John
Way off topic: What to do about dated and/or biased material that, perhaps isn’t intended to be?
The web site “ http://www.absoluteastronomy.com ” has a number of articles dealing with climate subjects. Two are:
LITTLE ICE AGE
http://www.absoluteastronomy.com/topics/Little_Ice_Age
MEDIEVAL WARM PERIOD
http://www.absoluteastronomy.com/topics/Medieval_Warm_Period
Each of these seems to use WIKIPEDIA as a sole source and to include much from the IPCC including the “hockey stick” of temperature and statements and references questioning both the LIA and the MWP.
Comments on WUWT have been made regarding the bias of an editor on WIKIPEDIA to the effect that materials of a skeptical nature regarding AGW are removed. I do not know this story and so cannot comment further.
However, the “hockey stick” temperature graph was initially questioned by Stephen McIntyre and a good source is from a conference presentation given on May 16, 2008 :
http://www.climateaudit.org/pdf/ohio.pdf
I know there are more recent additions to this story (ex. the censored data file) but I’m not familiar enough with this material to pull it together.
Questions about the MWP seem to be answered on the Idso’s site http://co2science.org/ with the weekly addition of a new research abstract confirming the MWP.
I do not know of a similar undertaking for the LIA, although I know there are many articles and references about it.
So the question: Might it be useful for readers here at WUWT who come across such material on sites that might be open to new or less biased ideas report them and, perhaps, once a week a thread could be started that could critique parts of the site’s material and then the whole thing could be directed to the site’s owners/operators/principals?
While any one of the folks so inclined, me being one, could send a comment to a site, I know I cannot do justice to all the work others have done. Further, I think a site’s owner(s) would be more inclined to reflect on their material if they know they are being seriously reviewed by a large group – not just an individual.
Sorry, to take up so much space off topic! Just wondering. Thanks, John

CodeTech

Sure sounds scary when the units change… most people I know, and that includes Canadians who have been metric since the 70s, can’t show me an estimate of 3mm. Here’s a free clue: a dime is about 1mm thick.
But hey, start throwing 30cm around, and now you’re on to something. “THIRTY! And since I don’t know what a cm is, I’ll assume it’s like a foot, right?” Sure.
But the real confusion comes when the con-men get involved, and start throwing METERS around. 30m! And it’s easy to show people that a meter is about a yard. So there’s a letter missing. Who cares? We’re all gonna drown!
And don’t forget those GREAT charts that all start at an arbitrary zero. That way the change can be REALLY UBER SCARY! Just like the CO2 ppm charts that all place zero at 280 so the change can be grossly exaggerated. I always have fun showing people the actual chart with zero at zero… they often are boggled.
Crash course in metric: An inch is about 2.5cm. A meter is about 40 inches. See? 40×2.5 = 100.
Each meter has: 1000mm, 100cm, 10dm. 1000 meters is a kilometer, which is 5/8ths of a mile. If you’re driving 50mph you’re going 80km/h.
By the way, when I see those charts, I don’t see a straight line shooting up to infinity, I see the top of a sine wave, about to start downward. Straight lines are so deceiving.

chillybean

It does not really seem to be worth making the graphs with this data. In the 2004 graph the “Measured” sea level was 20mm, yet on the 2009 graph the “Measured” sea level in 2004 was 10mm. If they are going to historically modify the measured data whats the point. Now I can understand modifying predictions or models but isn’t the Jason data from a satellite? Am I missing something obvious here?? I’m sure someone will explain it to me.

CodeTech

ps. in the first paragraph, I don’t think we’re measuring seals 😉

Anthony, your very second line refers to “seal level” graphs.
Now, we all know that polar bears just love seals, so I would imagine that when the “seal level” goes up, it is because there are less polar bears eating them.
In that case, we should probably get the clubbers out in order to cull the seal levels!

John F. Hultquist

I do not have the numbers but where the river is not channalized (as is the Mississippi) the sometimes yearly flooding deposits thin to thick layers of alluvium, clay and sand mostly, over the existing delta. When portions of the delta are raised in this manner the flood will go to lower parts and even build new land. When the flooding river cannot change its course because it is confined between levies it will flush all that material into the gulf or sea into which it discharges. This, in itself, ought to cause sea level to rise a bit as the material displaces the water upward. Thus, Bangladesh will rise because it is mostly delta of an uncontrolled alluvial river while the Mississippi delta will continue to disintegrate.

Rising seal level is very good news for the polar bears, I guess. 😉

Juraj V.

But..but the Copenhagen Climate conference told that the sea level (and temperature levels) rise beyond all projections?
Somewhere I saw sea level graph, based only of some high-quality measuring points. The rise was strongest up to 1960 and almost flattened after 2003.

masonmart

We also have to remember that there genuinely has been warming and one would expect rising sea levels as a result. The key thing as always is how much of the level rise one can pin on AGW and what will it do from now on. I’ve sailed in tropics and in the UK for 25 years now and I have seen no significant change in sea levels during that period.
A question, how do you measure MSL and the average annual increase given the number of variables that can affect sea level such as pressure, position of planets, wind, etc? Seems to me as dodgy as average surface temperature?

Mike Bryant

Hmmmm… the trend of about 3mm per year is based on satellite observations. Funny how satellites can look down from such great distances and at such great relative speeds at the heaving ocean and determine these measurements with millimeter precision, while other satellites can look down at the ice pack and miss the measurements by hundreds of thousands of square kilometers.
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…
Would love to see Dr. Morner comment here.
Thanks for putting some of these numbers into perspective.
Mike

Craig Allen

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!

NOAA’s Tides and Currents webpage is here:
http://tidesandcurrents.noaa.gov/index.shtml
It includes Sea Level Trends by State with a map showing that, for the majority of the contiguous US, the sea level rise has been less than 1 foot/century:
http://tidesandcurrents.noaa.gov/sltrends/sltrends.shtml
Select a state from the list on the left-hand side, then Click on a location and it provides a graph with trends.
They’ve also got graphs of the global network (PSMSL) Data:
http://tidesandcurrents.noaa.gov/sltrends/sltrends_global.shtml
Regards

John F. Hultquist

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.

James P

Measuring something as bumpy as the sea to +/-0.4mm can’t be easy 🙂
On a more serious note, what is the height relative to? Could it not equally be the land mass sinking..?

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.

DJ

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…
http://www.smh.com.au/news/national/byron-bay-wont-budge-over-rising-sea-liability/2007/05/19/1179497333614.html
http://informet.net/tuvmet/tide.html
http://news.bbc.co.uk/1/hi/sci/tech/5092218.stm
200 million people live within 1m of sea level… so these stories will be repeated countless times this coming century.

The Science

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.

Sid Brooks Australia

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 believe that to get a fix on altitude the operators are using fixed land based objects to obtain a reference base on each orbit or part of an obit, I further believe that they must be using continuous approximation calculations in their computers, and they must be referencing local tide tables for each satellite measurement taken.
Note that local tide tables make no allowance for barometric pressure and sea movement due to wind.
2/ If they use land base reference points, how certain are they that these points are stable enough for the purpose ?
Can some one tell us how they do this and how confident we should be about the stated measurements
I worry about the accuracy of many of the measurements quoted about things being published concerning our climate ie, How accurate are the measurements of the average temperature for the whole globe 100 years ago, indeed how accurately do we know that even today ?.
How do they measure the average temperature of the globe ?
Who measured pH of the sea within 0.1 pH 100 years ago, remembering that pH is a logarithmic scale ie you have to change the concentration oh hydrogen ions by 10 to cause a 1.0 pH change. If the solution is heavily “buffered” as sea water is, it would take a LOT of CO2 to reduce the pH of the oceans that are already very alkaline.
As a retired instrumentation engineer I wouldn’t be able to even measure the average temperature of the interior of my modest house within +/- 2 deg C let alone 0.1 deg C.
All of these things and others pass through my mind when I hear all of the doomsday prophets speaking. I may well be mistaken, I do not believe in conspiracy theories, but at the moment I feel that the kids (big and small) are too busy playing with their computer games to see the real world.
My son is head of mathematics at a university and he doesn’t believe that you can properly model climate or economics to predict the future as we don’t know enough about the variables involved .
Thanks for this forum

Katherine

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?

stephen richards

I remember using Ahrennius (sorry bout spelling) curve many years ago when looking for failure mechanisms at semiconducting junctions.
A curve like the sea level one above would indicate 2 failure types, that is, of different values in electron volts. One before about 2003/4 and one after. It is a very obvious change in ‘mechanism’.

Gerard

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.

Andrew P

Kaboom (00:33:12) :
Anthony, your very second line refers to “seal level” graphs.
Now, we all know that polar bears just love seals, so I would imagine that when the “seal level” goes up, it is because there are less polar bears eating them.
In that case, we should probably get the clubbers out in order to cull the seal levels!

Perhaps it is the additional displacement caused by the growing seal population that has caused the increased sea levels? 😉

Paul S

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 . . .

How much of the rise can be attributed to siltation from rainfall and wind eroding land mass above sea level?

Malaga_View

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…

NS

“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
……….
Craig Allen (01:02:02) :
Just eight points I’d like to make.
………”
Perhaps valid points but if you build a house on a flood plain, don’t be surprised when it gets flooded.
Sea levels rise, and fall, over time.

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.

Hasse@Norway

Correct me if I’m wrong. But, isn’t these satelite numbers adjustet against the Hong Kong tide gauge??? And Hong Kong is sinking 2-3mm/year. Could this leveling of mean that hong Kong has stopped sinking? 😉

Juraj V.

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.

Paul R

Now that the Antarctic ice shelf has collapsed sea levels will show a sharp rise in levels. The Penguin populations of Antarctica will be threatened due to having to dive deeper for food after years of suffering altitude sickness from being elevated on top of a thickening ice sheet.
Peter Garret, Australian environment minister had this to say while moving his arms in a strange manner in relation to his hips.
“I don’t think that there’s any doubt that global warming is contributing to what we’ve seen both on the Wilkins Ice Shelf and also more generally in Antarctica,” he said.
“And it is the case that scientists, because of the fact of the Antarctic’s unique and critical role in the world’s climate system, are focusing very strongly on climate change research and also potential impacts.
“This is a really significant mass of ice and it is the case that scientists previously had identified that it might potentially start to break away or collapse and that that would be as a consequence of warming.”
Mr Garrett has dismissed the suggestion the shelf’s collapse is simply the latest in a very long history of such events. Doh !
http://www.abc.net.au/news/stories/2009/04/07/2536710.htm
He has the power and the passion.

vg

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

Manfred

@craig
there are thousands of scientist out there, who have the mission to figure out the dyre consequences of the projected sea level rise and they are very creative in doing this.
the ipcc projections, however, are not much different from the experience of the last century, and hardly anybody did take notice in the past or suffer from anything related to the rise. the previous 30 cm sea level rise was a non-event and the next 30 cm rise (if it happens at all) will be the same.

vg

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…

vg

Sid Brooks.. Actually its true I ain’t seen ANY change in sea levels anywhere since I was a child 50 years ago! Has anyone else?

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.

Mike C

Hey, if you want a large tidal range, don’t forget about the Bay of Fundy up here in Nova Scotia. 😎
http://en.wikipedia.org/wiki/Bay_of_Fundy#Tides

Paul

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.

DJ (01:33:42) : Part II
Just had a look at one or two of your links. I’m sure this wouldn’t be done deliberately, but the BBC needs to be careful it doesn’t confuse sea level rise due to global warming with other factors such as postglacial rebound and coastal erosion. Note that the Thames area is sinking slowly (and will continue to do so for a good while yet) due to the effects of the LGM. See http://en.wikipedia.org/wiki/Post-glacial_rebound where there is a specific mention of the the Thames problems.
Incidentally Sea Level rises over the past 20,000+ years can be found here:
http://en.wikipedia.org/wiki/Sea_level_rise.

“Gerard (01:47:55) :
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
….
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.
…”
I think as some pointed out above this may be a problem of math challenged individuals. The high estimate of sea level rise on the charts above is 80 cm with the normal predictions being 20 to 60 cm. This could get changed into 6 meters easy enough. Or someone is really extrapolating melt from the western peninsula of Antarctica which has warmed in the last few decades to the whole of Antarctica which is getting colder. Of course it is also possible that the trend is not linear and sea level may drop over the next hundred years.

Alan the Brit (00:08:42) :
I believe our fingernails grow more than this rate per annum.

13 angstroms per second! I remember calculating this in college. I had smashed my finger and measured how fast the bruised area of the fingernail grew back over a few weeks, and this is one of my more astounding “fun facts” from those days… I think it’s reasonably close.
13e-10m/s*3600*24*365=.041m/yr, or 4cm per year. So yes, our fingernails grow MORE THAN 10x faster than sea level rise.
I’ll have to send this message to a couple of my college buddies… HAH! I KNEW this little tidbit would come in handy! Only took 27 years.
Stated another way, sea level is rising 1 micron every 2 HOURS!!!. .0005 inches per day! Run for the hills!

O. Weinzierl

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.

Richard111

I read recently the WAIS is melting at 150 cubic kilometers if ice each year. I make that 136.4 cubic kilometers of water. This will raise sea levels by 0.4mm (zero point four millimeters) which is about the error bar level of all the above graphs. Quite frightening.

Edouard

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 ;-)))

WestHoustonGeo

Quoting:
“Many coastal regions are currently protected from storm surges by wetlands and marshes (think New Orleans). ”
Commenting:
Don’t think New Orleans. N.O. is built on a river delta and the surrounding wetlands were drained to make more city. Most of it is well below sea leve and survives only by extensive man-made dikes. The French quarter is above sea level and was not flooded.
It is an absolutely stupid place for a ctiy but it won’t go away. But only an uniformed or dishonest person would try to use it as a scary example of what’s going to happen to Floorida.

Ron de Haan

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.

David Porter

CodeTech (00:23:57) :
You missed the big scary one; 300 mm/century. That would give Craig kittens.

Jared

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?

Squidly

Craig Allen (01:02:02) :
Just eight points I’d like to make.

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!

Craig, using New Orleans is a very poor way of illustrating doom and gloom for sea level rise for very many reasons. First and foremost, New Orleans did not flood because of any sea level rise, it is already below sea level! The New Orleans flood was certainly man made however, it was a failure in maintenance, and as you cited, was warned about for decades!
Seems to me, if you cannot fix something that you know about for decades, something as simple as maintenance, then sea level rise becomes rather moot. If your that stupid, then you should probably drown. I am continually amazed at how people think they can park their rears anywhere they wish and they expect nature to respect them. Such stupidity and arrogance!