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Romm reports: "The oceans are rising 60 per cent faster than the IPCC's latest best estimates, according to the new research."

A cyclist makes his way past a stranded taxi on a flooded New York City street as Tropical Storm Irene passes through the city. (photo: Peter Morgan/AP)
A cyclist makes his way past a stranded taxi on a flooded New York City street as Tropical Storm Irene passes through the city. (photo: Peter Morgan/AP)

Sea Levels Rising 60% Faster Than Expected

By Joe Romm, ThinkProgress

30 November 12


new study, "Comparing climate projections to observations up to 2011," confirms that climate change is happening as fast — and in some cases faster — than climate models had projected. The news release explains:

The rate of sea-level rise in the past decades is greater than projected by the latest assessments of the IPCC, while global temperature increases in good agreement with its best estimates. This is shown by a study now published in the journal Environmental Research Letters. Stefan Rahmstorf from the Potsdam Institute for Climate Impact Research (PIK) and his colleagues compare climate projections to actual observations from 1990 up to 2011. That sea level is rising faster than expected could mean that the Intergovernmental Panel on Climate Change's (IPCC) sea-level rise projections for the future may be biased low as well, their results suggest.

As Dr. Rahmstorf notes, "the new findings highlight that the IPCC is far from being alarmist and in fact in some cases rather underestimates possible risks."

The oceans are rising 60 per cent faster than the IPCC's latest best estimates, according to the new research. The researchers compared those estimates to satellite data of observed sea-level rise. " Satellites have a much better coverage of the globe than tide gauges and are able to measure much more accurately by using radar waves and their reflection from the sea surface," explains Anny Cazenave from LEGOS. While the IPCC projected sea-level rise to be at a rate of 2 mm per year, satellite data recorded a rate of 3.2 mm per year.


Figure: Sea level measured by satellite altimeter (red with linear trend line) … and reconstructed from tide gauges (orange, monthly data from Church and White (2011))…. The scenarios of the IPCC are shown in blue (third assessment) and green (fourth assessment); the former have been published starting in the year 1990 and the latter from 2000.


The release notes, "The increased rate of sea-level rise is unlikely to be caused by a temporary episode of ice discharge from the ice sheets in Greenland or Antarctica or other internal variabilities in the climate system, according to the study, because it correlates very well with the increase in global temperature."

As sea level rises, storm surges worsen, coastal populations are put at risk, and salt water infiltrates rich deltas. For more on likely future sea level rise, see "New Studies on Sea Level Rise Make Clear We Must Act Now" and "JPL bombshell: Polar ice sheet mass loss is speeding up, on pace for 1 foot sea level rise by 2050."

On the subject of global warming, the release explains:

"Global temperature continues to rise at the rate that was projected in the last two IPCC Reports. This shows again that global warming has not slowed down or is lagging behind the projections," Rahmstorf says. Five global land and ocean temperature series were averaged and compared to IPCC projections by the scientists from Potsdam, the Laboratoire d'Etudes en Géophysique et Océanographie Spatiales (LEGOS) in France and the US based Tempo Analytics. To allow for a more accurate comparison with projections, the scientists accounted for short-term temperature variations due to El Niño events, solar variability and volcanic eruptions. The results confirm that global warming, which was predicted by scientists in the 1960s and 1970s as a consequence of increasing greenhouse concentrations, continues unabated at a rate of 0.16 °C per decade and follows IPCC projections closely.


Figure. Observed annual global temperature, unadjusted (pink) and adjusted for short-term variations due to solar variability, volcanoes and ENSO (red) as in Foster and Rahmstorf (2011). 12-months running averages are shown as well as linear trend lines, and compared to the scenarios of the IPCC (blue range and lines from the third assessment, green from the fourth assessment report). Projections are aligned in the graph so that they start (in 1990 and 2000, respectively) on the linear trend line of the (adjusted) observational data. your social media marketing partner


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-56 # Malcolm 2012-11-30 23:08
My bs meter is far more accurate than their sea level monitoring. Do any of you know how many tricky parameters are involved in measuring sea level? And then, to claim the ability to measure SIXTY percent faster than EXPECTED.

Sorry, folks; ain't possible.

thumbs away.
+5 # pbbrodie 2012-12-01 10:20
I feel quite confident in the knowledge that these scientists, who do this for a living, are way more qualified to accurately measure the sea level, than you are to criticize their work.
What information do you claim to posses that shows this to be impossible? My brother designs radar systems for the defense department and he assures me that sea level can be quite accurately measured from satellites by radar and laser. Do you have any qualifications to challenge this? I sincerely doubt it. You are most likely just another yahoo with a BS meter.
+14 # AReber 2012-12-01 12:04
"My bs meter is far more accurate than their sea level monitoring."

You just disqualified yourself from any meaningful role in the discussion.
+7 # Smiley 2012-12-01 13:51
I don't get it. Are you actually questioning whether warming water expands or that ice turns into water when it melts?
0 # ksan51 2012-12-04 18:37

Really Malcolm? I know that you are a skeptic, but do you not understand that the primary way to measure sea level today is with satellites?

There is nothing "tricky" about it. They use altimeters and radio waves concurrently to measure sea levels from orbit.

At the same time, they use tidal gauges and drifting buoys (which use sonar to measure their distance from the sea bed.

All of these measurements are used to create trend lines that have consistently shown that sea level is rising and the rise is accelerating.

Here is the link to a peer reviewed article on the subject:

I appreciate your skepticism, and I wish more people were willing to do as much research as you do, but as your constant posting here has shown, you simply are muddying the waters in this argument.

You can keep bringing up arguments, but there are mountains of data out there that fly directly in the face of your arguments.
-45 # Malcolm 2012-11-30 23:19
What a riot! Article says, "Observed annual global temperature, unadjusted (pink) and adjusted for short-term variations due to solar variability, volcanoes and ENSO (red)"

That is so funny. y'know, not long ago, the warmists had "consensus" that solar variability was some skeptics' plot to destroy their arguments. Now, though, when you see the temperature has kind of stagnated, well, it must be the solar variability. Couldn't be that their theories are full of baloney. Nah. When the theories don't work, we'll just ADJUST them. ¡No problema!
+21 # Smiley 2012-12-01 02:59
Gee Whiz Malcolm,
Pull your head out of the sand. The facts are overwhelming. We can't fix it if we're afraid to look at what we're doing.
-18 # Malcolm 2012-12-01 11:11
And pull your head... oh, never mind. We can't fix it if we are basing our repairs on bogus information, in case you haven't thought about it.
+21 # Bruce Gruber 2012-12-01 05:26
So, Malcolm, you're investing in land on Long Island and in New Orleans AND Florida, right?
-15 # Malcolm 2012-12-01 11:13
Wrong. I'm investing in land in Jump Off Joe Creek Valley.

In your opinion, sir, investment i these other areas a criterion for "correct thinking" aka Politically Correct thought?

If so, have you started buying land there?

-19 # Malcolm 2012-12-01 11:21
Sorry, Bruce; of course you won't be buying land in Floriduh, Long Island or NOLA. But you WILL, I presume, be buying land in the Rockies. Right?

Two can play at your silly game.
+9 # pbbrodie 2012-12-01 10:15
Where do you see any stagnation in the graph that shows a steady increase?
You are the riot.
-5 # 2012-12-01 00:02
At that rate I am so glad at 68 I and my family won't have to join the new Ark parade. God will have me long before the sharks.

By next gen they will have learned to shave the ice to water the deserts or put their unemployed to desalinating water for derert depletion and not to the 2% for hoarding along with governments wast on Wars for land those deserts can grant for water.
-4 # sagittarius 2012-12-01 07:38
It isn't a secret that sea levels have risen about 100 meters in the last 10,000 yrs.
Isn't that about 1 meter per 100 years?
Isn't that about 1000 mm per 100 years?
Isn't that about 10 mm per year?
What's the big deal about 3.2 mm / yr rise?

If these calculations are wrong, please advise. If so, then the 3.2 mm/yr is only about 30% as fast as sea levels have risen since the last Ice Age ended.....
-7 # Malcolm 2012-12-01 12:36
SAgittarius, that's a very interesting point. I think the data i've seen show sea level rises a bit less than that, but i've seen so many diverse ESTIMATES that i'm not going to dispute your data.

In fact, a few years ago, a fellow named Ballard found a settlement about 300 feet beneath the Black Sea. He had some freshwater mollusks carbon dated at around 7500 years. Last I heard, nobody has yet carbon dated the wooden building found there, which would be more accurate. Probably I just don't know where to find that info.

Regardless, if the building started getting flooded 7500 years ago, that would be 0.04 feet per year, or 12 mm/year.

I don't think this is proof, at this point, of anything, because there are some who believe the Black Sea flooded SUDDENLY, when the Mediterranean rose high enough to pour water into the Black Sea. I would doubt that, but that's only my opinion.

If you DO use this data to help determine historical sea level rises, though, they strengthen your figure of 10 mm/year, that's for sure!
0 # ksan51 2012-12-04 20:38
You are assuming that the glacial melt caused by the end of the last ice age happened continuously over the intervening time between now and then.

This is faulty though.

The last Ice Age (a brief one called the Younger Dryas)ended roughly 11,500 years ago. The giant glaciers that were the indicator of the last ice age all but disappeared after roughly 2000 years.

Your figure of 100 meters is actually a bit low. 120 meters is the more likely amount.

So based on those numbers, in the 2 millenia after the last ice age, sea level rose by 60 mm / yr (120,000 mm / 2000 years)

The data that most geologists and climate scientists have gathered show very little rise after that point.

So while 3.2 mm / yr sounds small, it is a vast increase over the negligible amount that sea levels have risen since the last glaciers of the Ice Age melted.

Here is a link to a peer-reviewed article to help illustrate how sea levels are rising and the rate at which they are rising is accelerating:

Now, yes that report is from 2007, so if anything, the situation is more dire, as this article on RSN states. But the chapter I linked to is very thorough and shows the rising trend very clearly.
+3 # handmjones 2012-12-01 08:08
Wonder what portion of sea level rise is due to pumping fossil water into the biosphere?
-6 # MidwestTom 2012-12-01 08:30
According to NOAA the oceans actually FELL by about 1/2 inch last year. they attributed it to water retention in the Amazon basin.
+5 # pbbrodie 2012-12-01 10:13
Can you please provide a link to this data? I haven't seen anything like this anywhere but from you.
-9 # Malcolm 2012-12-01 11:39
Try this link:

THIS article shows sea level dropping by 1/4 inch between summer 2010 and summer 2011. (Tom, werer you thinking perhaps of 1/2 CENTIMETER?) Possibly this is due to the global cooling since 1998. Possibly it's because it's so nearly impossible to ACCURATELY detect small changes in sea level.

Anyone who tries to do so will find that there are a helluva lot of variables, each of which is large enough to seriously mask a 3 mm per year rise, or a 1/4 inch per year fall.

Among others, there's wind; waves; tides; seiche; subsidence caused by removal of gas, oil, and water; continental uplift and subduction; perihelion and aphelion; floods raising sea levels; monitoring equipment inaccuracies; and tsunamis. And that's only the ones that quickly come to mind.

Trying to factor in, and correct for, all these anomalies makes estimates of small sea level changes very imprecise, unfortunately.
-11 # Malcolm 2012-12-01 12:39
With all these built-in inaccuracies, I just love it that IPCC makes this claim:

"While the IPCC projected sea-level rise to be at a rate of 2 mm per year, satellite data recorded a rate of 3.2 mm per year."

3.2 mm/year! Not 3.1 mm/year; not 3.3 mm/year, but 3.2 mm/year!!!

Anyone ever heard of FALSE ACCURACY?
+4 # brenda 2012-12-01 13:32
"Some see signs in the sky, and their right.

Some see signs in the sky , and say 'Bah'.

But all of us will be at the mercy of whatever came after the signs in the sky, and be screwed because we've crossed the point of return."

Thus it is written that man with all his intelligence and skepticism are prone to become extinct, while the insects and fish evolve to be the next masters of this world.
-9 # Malcolm 2012-12-01 17:00
Some see signs in the sky and say, "Hey, those clouds look like Al Gore, with his pockets overflowing with Carbon Trading bucks!"
-5 # Malcolm 2012-12-01 20:39
I've been seeing a lot of statements suggesting Katrina, or Sandy, or various other weather events, are "proof" that we're having climate change, or sometimes "the face of climate change".

I have another proof. This is a great story, one which i've known about (on a local level) for many, many years. Many (i should probably say "most") people in Oregon's Rogue Valley think the flood of 1964 was the highest possible, majorly bad flood. "They call it "The Big One".

The Rogue, at Grants Pass, was actually eight feet higher at its peak flow of December 1961. Hard to imagine, but true.

Today my Calif friend sent me this article; I hope some of you sheople/AGW followers can figure out how it proves anthropogenic global warming. If so, you're welcome. This sounds like fiction. Surely, all these rivers and creeks, ALL OVER THE AMERICAN WEST, couldn't have gotten THAT out of hand, that out of bank, that outrageously destructive.
+4 # Smiley 2012-12-01 21:58
I don't think anyone has suggested that there weren't catastrophic climatic events in the past. When they start becoming more regular events (as they are around the world)that is when you can start thinking of them as the "face of climate change".

I don't believe you would be doubting climate change if you were an Eskimo or South Sea Islander.

So far, here in Oregon we have not experienced any extreme changes, but we haven't had a really cold winter in many years. They used to be common. Have you seen the pictures of cars driving across the Colombia from Portland to Vancouver?
-2 # Malcolm 2012-12-02 18:54
Smiley, those are good points. What ticks me off is hearing-with great regularity-thin gs like "well, hurricane Sandy PROVES that global warming is real." And so forth. So many folks use this kind of ad hoc argument that I just can't help pointing out that every big storm, every big drought, etc are not proof of anything, since they've been happening for eons.

And I'm sorry you think I "doubt climate change". I am skeptical of all the claims made about it's causes, and am not 100% convinced that there is adequate data to prove that the earth is warming. It may well be. Certainly there is some evidence of it, but there's plenty of evidence that AGW is not true, as well.

I've seen the cars driving across the Columbia River, yes. I believe that was several years in the teens, right? Frankly, I'd prefer the current lack of extreme weather to another decade like that one.
-2 # Malcolm 2012-12-02 18:55

My biggest peeve, actually, is this bs about CO2. I just have a very hard time with assigning CO2 blame for warming. For reasons I hope I've made clear many times over. Interestingly, I just read some info that supports Don Easterbrook's prognostication that PDO is entering a cool phase, which he speculates correlates to sun spot activity (though he acknowledges that it's impossible to be certain)

This was written by main stream scientists, i think at JPL, but if you're interested, I'll try to find the link.

Don shares my concern that we're risking the health of third world countries by potentially destroying economies there (and first world) with proposed carbon trading. Which is why i feel strongly we need to avoid cap and trade.
-2 # Malcolm 2012-12-02 19:09
I guess I was just remembering JPL because of the article's referencing
Josh Willis, JPL oceanographer and climate scientist. I can't tell who authored it. But it WAS published by Nasa:

Nasa/jpl is acknowledging what Don has been saying for at least 15 years, which is, imo, unprecedented among warmist leaning organizations such as Nasa:

"Unlike El Niño and La Niña, which may occur every 3 to 7 years and last from 6 to 18 months, the PDO can remain in the same phase for 20 to 30 years. The shift in the PDO can have significant implications for global climate, affecting Pacific and Atlantic hurricane activity, droughts and flooding around the Pacific basin, the productivity of marine ecosystems, and global land temperature patterns. #8220;This multi-year Pacific Decadal Oscillation ‘cool’ trend can intensify La Niña or diminish El Niño impacts around the Pacific basin,” said Bill Patzert, an oceanographer and climatologist at NASA's Jet Propulsion Laboratory, Pasadena, Calif. “The persistence of this large-scale pattern [in 2008] tells us there is much more than an isolated La Niña occurring in the Pacific Ocean.”

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