Overpeck says 3 feet, real world sea level data says no way

From high and dry  University of Arizona, home of the world famous parking lot USHCN weather station, we have word via Eurekalert that a simulation says it will be bad as “sea levels are expected to rise by up to three feet by the end of this century”.

They say we can now ignore thermal expansion of seawater due to rising temperatures because it “contributed only slightly to rising sea levels”. It may be too late already, gosh. At the present 3 mm per year rate measured by satellite, and with 89.5 years left, that works out to 89.5yrs x 3.1mm/yr = 277.5 mm which works out to 0.91 feet or 10.9 inches. UofA, and especially Jonathan Overpeck are going to have to kick it into high gear if they are going to make three feet by 2100.

Rising oceans — too late to turn the tide?

Melting ice sheets contributed much more to rising sea levels than thermal expansion of warming ocean waters during the Last Interglacial Period, a UA-led team of researchers has found.

Simulation of Rising Sea Levels

If sea levels rose to where they were during the Last Interglacial Period, large parts of the Gulf of Mexico would be under water (red areas), including half of Florida and several Caribbean islands. Credit: Jeremy Weiss, Department of Geosciences, The University of Arizona

Thermal expansion of seawater contributed only slightly to rising sea levels compared to melting ice sheets during the Last Interglacial Period, a University of Arizona-led team of researchers has found.

The study combined paleoclimate records with computer simulations of atmosphere-ocean interactions and the team’s co-authored paper is accepted for publication in Geophysical Research Letters.

As the world’s climate becomes warmer due to increased greenhouse gases in the atmosphere, sea levels are expected to rise by up to three feet by the end of this century.

But the question remains: How much of that will be due to ice sheets melting as opposed to the oceans’ 332 million cubic miles of water increasing in volume as they warm up?

For the study, UA team members analyzed paleoceanic records of global distribution of sea surface temperatures of the warmest 5,000-year period during the Last Interglacial, a warm period that lasted from 130,000 to 120,000 years ago.

The researchers then compared the data to results of computer-based climate models simulating ocean temperatures during a 200-year snapshot as if taken 125,000 years ago and calculating the contributions from thermal expansion of sea water.

The team found that thermal expansion could have contributed no more than 40 centimeters – less than 1.5 feet – to the rising sea levels during that time, which exceeded today’s level up to eight meters or 26 feet.

At the same time, the paleoclimate data revealed average ocean temperatures that were only about 0.7 degrees Celsius, or 1.3 degrees Fahrenheit, above those of today.

“This means that even small amounts of warming may have committed us to more ice sheet melting than we previously thought. The temperature during that time of high sea levels wasn’t that much warmer than it is today,” said Nicholas McKay, a doctoral student at the UA’s department of geosciences and the paper’s lead author.

McKay pointed out that even if ocean levels rose to similar heights as during the Last Interglacial, they would do so at a rate of up to three feet per century.

“Even though the oceans are absorbing a good deal of the total global warming, the atmosphere is warming faster than the oceans,” McKay added. “Moreover, ocean warming is lagging behind the warming of the atmosphere. The melting of large polar ice sheets lags even farther behind.”

“As a result, even if we stopped greenhouse gas emissions right now, the Earth would keep warming, the oceans would keep warming, the ice sheets would keep shrinking, and sea levels would keep rising for a long time,” he explained.

They are absorbing most of that heat, but they lag behind. Especially the large ice sheets are not in equilibrium with global climate,” McKay added. ”

Jonathan Overpeck, co-director of the UA’s Institute of the Environment and a professor with joint appointments in the department of geosciences and atmospheric sciences, said: “This study marks the strongest case yet made that humans – by warming the atmosphere and oceans – are pushing the Earth’s climate toward the threshold where we will likely be committed to four to six or even more meters of sea level rise in coming centuries.”

Overpeck, who is McKay’s doctoral advisor and a co-author of the study, added: “Unless we dramatically curb global warming, we are in for centuries of sea level rise at a rate of up to three feet per century, with the bulk of the water coming from the melting of the great polar ice sheets – both the Greenland and Antarctic Ice Sheets.”

According to the authors, the new results imply that 4.1 to 5.8 meters, or 13.5 to 19 feet, of sea level rise during the Last Interglacial period was derived from the Antarctic Ice Sheet, “reemphasizing the concern that both the Antarctic and Greenland Ice Sheets may be more sensitive to warming temperatures than widely thought.”

“The central question we asked was, ‘What are the warmest 5,000 years we can find for all these records, and what was the corresponding sea level rise during that time?'” McKay said.

Evidence for elevated sea levels is scattered all around the globe, he added. On Barbados and the Bahamas, for example, notches cut by waves into the rock six or more meters above the present shoreline have been dated to being 125,000 years old.

“Based on previous studies, we know that the sea level during the Last Interglacial was up to 8.5 meters higher than today,” McKay explained.

“We already knew that the vast majority came from the melting of the large ice sheets in Greenland and Antarctica, but how much could the expansion of seawater have added to that?”

Given that sea surface temperatures were about 0.7 degrees warmer than today, the team calculated that even if the warmer temperatures reached all the way down to 2,000 meters depth – more than 6,500 feet, which is highly unlikely – expansion would have accounted for no more than 40 centimeters, less than a foot and a half.

“That means almost all of the substantial sea level rise in the Last Interglacial must have come from the large ice sheets, with only a small contribution from melted mountain glaciers and small ice caps,” McKay said.

According to co-author Bette Otto-Bliesner, senior scientist at the National Center for Atmospheric Research (NCAR) in Boulder, Colo., getting the same estimate of the role ocean expansion played on sea level rise increases confidence in the data and the climate models.

“The models allow us to attribute changes we observe in the paleoclimate record to the physical mechanisms that caused those changes,” Otto-Bliesner said. “This helps tremendously in being able to distinguish mere correlations from cause-and-effect relationships.”

The authors cautioned that past evidence is not a prediction of the future, mostly because global temperatures during the Last Interglacial were driven by changes in the Earth’s orbit around the sun. However, current global warming is driven by increasing greenhouse gas concentrations.

The seasonal differences between the northern and the southern hemispheres were more pronounced during the Last Interglacial than they will be in the future.

“We expect something quite different for the future because we’re not changing things seasonally, we’re warming the globe in all seasons,” McKay said.

“The question is, when we think about warming on a global scale and contemplate letting the climate system change to a new warmer state, what would we expect for the ice sheets and sea levels based on the paleoclimate record? The Last Interglacial is the most recent time when sea levels were much higher and it’s a time for which we have lots of data,” McKay added.

“The message is that the last time glaciers and ice sheets melted, sea levels rose by more than eight meters. Much of the world’s population lives relatively close to sea level. This is going to have huge impacts, especially on poor countries,” he added.

“If you live a meter above sea level, it’s irrelevant what causes the rise. Whether sea levels are rising for natural reasons or for anthropogenic reasons, you’re still going to be under water sooner or later.”

###

Reference:

McKay, N., J. T. Overpeck, and B. Otto-Bliesner (2011). The role of ocean thermal expansion in Last Interglacial sea level rise. Geophys. Res. Lett., doi:10.1029/2011GL048280, in press. A version of the accepted paper is available online at the Geophysical Research Letters site: http://www.agu.org/journals/gl/papersinpress.shtml

===========================================================

Update: Leif Svalgaard has the full paper here. Thanks Leif.

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John M

Maybe he’s counting on one hell of a glacial isostatic adjustment.

Roy Weiler

We might as well just give up now. The tipping points have been reached, our only hope is adaptation!!
/sarc

Bill Illis

Corrections to the article above (obviously written by scientists who don’t care about facts), last interglacial +2.25C higher in global temperature versus today – sea level about 4-5 metres higher than today – CO2 about 100 ppm lower than today.

John F. Hultquist

Peyote! Maybe?

I wonder if I could show this to someone living on a ocean front lot anywhere and convince them to sell me their estate for 10 cents on the dollar?

What was I thinking?
With this disaster confronting us, it’s 2 cents on the dollar!

terrybixler

Is this guy a sitcom writer or a scifi wannabe. The script was made into a movie already. Of course he will be dead and gone by the time his prediction is yet another AGW failure. Ask big Al about Mann’s hockey stick. Funny how the solar minimum kind of puts these creeps to shame.

Theo Goodwin

As the Warmista have been given more and more rope, it has become clear that their obsession with Gaia Models has become an excuse not to do actual research that could lead to the formulation of actual physical hypotheses. It is as if “permanent graduate student syndrome” has fallen over the whole lot of Warmista. They are now just entertaining one another.

kadaka (KD Knoebel)

Up to three feet by 2100? That’s it? That’s minor league prognostication, amateur hour stuff. Let’s see how the Big-Time Professional Climate Scientists™ do it!
From Spiegel Online, said article discussed here on WUWT recently:

NASA climate researcher James Hansen, for example, warns in a paper published this month that sea levels could rise by five meters in the next 90 years — nine times higher than the maximum cited in the last IPCC report. He insists that he has found indications that sea levels in the future could rise by as much as five centimeters per year.

Five Meters by 2100, not some wimpy “three feet.” Now THAT is how you get people motivated! THAT is how you do CLIMATE SCIENCE™!

Ursus Augustus

Thankyou Professor Overpeck and student McKay for warning us just how bad it might get. On the other hand, isn’t it a relief that those ancient humans didn’t completely destroy the planet with the discovery of fire. We have a second chance! BAN FIRE. FIRE POLLUTION WILL DESTROY THE PLANET! . FIRE IS THE ROOT OF ALL EVIL. BAN HEAT! HEAT TAX NOW!!!

Latitude

warmest 5,000-year period during the Last Interglacial, a warm period that lasted from 130,000 to 120,000 years ago.
On Barbados and the Bahamas, for example, notches cut by waves into the rock six or more meters above the present shoreline have been dated to being 125,000 years old.
“Based on previous studies, we know that the sea level during the Last Interglacial was up to 8.5 meters higher than today,” McKay explained.
======================================================================
“As a result, even if we stopped greenhouse gas emissions right now, the Earth would keep warming, the oceans would keep warming, the ice sheets would keep shrinking, and sea levels
would keep rising for a long time,” he explained.
======================================================================
The authors cautioned that past evidence is not a prediction of the future, mostly because global temperatures during the Last Interglacial were driven by changes in the Earth’s orbit around the
sun. However, current global warming is driven by increasing greenhouse gas concentrations.
======================================================================
This has to be one of the funniest papers I’ve even seen………………………..
and they are not the slightest bit embarrassed to put their names to it

Michael D Smith

The Last Interglacial is the most recent time when sea levels were much higher and it’s a time for which we have lots of data
Did they take the sea level data in cubits back then? The oldest sea level measurements are MUCH older than I thought. I wonder what the worldwide sea level measurement standards were back then, and whether they freely shared their data when publishing. I haven’t seen a peer reviewed journal older than 72,000 years, so this is indeed quite intriguing…

Martin Clauss

As an Arizona State U. graduate, we think of that ‘other university in Tuscon’ as inferior ( . .uh, just good-natured rivalry, please don’t infer any ad-hom attacks . . ).
Though reports like this make it VERY EASY to tease them. They claim both the atmosphere and oceans are warming, but over the last several years, NEITHER are happening. Sea level rise has taken a hiatus the past year or so, and there is nothing to show it will increase at any ‘alarming’ rate. And if the sun continues along the recent path or solar cycles, continued warming is unlikely, at least for a few decades (based on the articles I read).
Then the final statement (“If you live a meter above sea level, it’s irrelevant what causes the rise. Whether sea levels are rising for natural reasons or for anthropogenic reasons, you’re still going to be under water sooner or later ”) is even more absurd. How ever long it might take IF seal levels rise by a meter, people will obviously adapt and move away.
. . . amazing how ‘alarmist’ they continue to be . . .

“ssquared8484 says: I wonder if I could show this to someone living on a ocean front lot anywhere and convince them to sell me their estate for 10 cents on the dollar?”
Why not ask the Goracle and find out? ;-p

Rick Bradford

Three feet? Five meters? Wimps.
> Andrew Bolt [Australian radio presenter]: Dean of science…suggesting rising seas this next century of up to 100 metres, or Al Gore six metres. When I see things like that I know these are false. You mentioned the IPCC report; that suggests, at worst on best scenarios, 59 centimetres.
> Robyn Williams: Well, whether you take the surge or whether you take the actual average rise are different things.
> Andrew Bolt: I ask you, Robyn, 100 metres in the next century…do you really think that?
> Robyn Williams: It is possible, yes.

J. Felton

I have my own simulation on my home computer. It’s called ” Flight Simulator 2010.” I can beat the final level.
Doesnt mean I can tell pilots how to fly.

Mike McMillan

I figure I’ve got 2700 years before I need to build a dock in the front yard. As to Dr Hansen’s 5 meter rise, NASA needs to quit wasting their drug testing on pilots and concentrate on where it’s really needed.

DesertYote

“We already knew that the vast majority came from the melting of the large ice sheets in Greenland and Antarctica, but how much could the expansion of seawater have added to that?”
###
I guess the melting of the holarctic ice sheet covering half of North America and Eurasia had nothing to do with it.

Dave N

So:
Sea-levels could rise 3 feet, or several metres, or 100 metres, or pick a number in between.
Temperatures could rise anywhere from around 2 degrees to around 6 degrees.
We could have lots of snow, or it could become a thing of the past.
There could be more intense storms, or just more of them.
There could be more floods or more droughts.
These are examples from their “settled science”. The only thing that is settled is their extreme inability for rational thought.

DesertYote

I would like to ask a simple CO2 related question. This has been bothering for some time.
It seem that the forcing due to CO2 would be logarithmic to the concentrations of all greenhouse gases combined, not just CO2 alone. I other words given an atmosphere A, with x ppm CO2 and y ppm H2O and atmosphere B, with x ppm CO2 and 2y ppm H2O. Increasing the CO2 concentration in both would result in the change of forcing in A being greater then the change in forcing in B.
Does this make sence?

Tom in Florida

To me the question that should be asked is:
If “normal” sea levels during an interglacial are higher than now, what’s keeping them so low?

Theo Goodwin

Latitude says:
July 18, 2011 at 6:21 pm
Indicting them with their own words! How could you? They are just children after all, Hansen’s children.

Duster

Sea levels have been higher than present during the early Holocene and possibly the mid-Holocene. Numerous studies have documented this globally.
Holocene highstand, Thailand, higher than present:
http://www.sciencedirect.com/science/article/pii/0743954792900143
Pacific islands experienced high stands of 1.6 to 2.6 meters above present levels:
http://www.jstor.org/pss/4299192
Tropical highstands are suggested to be typically ca. 3 m. above present, with subsequent declines linked to glacial isostatic adjustments which increased basin volumes as GIA proceeded:
http://champs.cecs.ucf.edu/Library/Journal_Articles/pdfs/On%20the%20origin%20of%20late%20Helocene%20sea-level%20highstands%20within%20equatorial%20ocean%20basins.pdf

Theo Goodwin

Dave N says:
July 18, 2011 at 7:16 pm
“So: Sea-levels could rise 3 feet, or several metres, or 100 metres, or pick a number in between.
Temperatures could rise anywhere from around 2 degrees to around 6 degrees.
We could have lots of snow, or it could become a thing of the past.
There could be more intense storms, or just more of them.
There could be more floods or more droughts.”
The Old Testament does a better job of prediction. Warmista do not understand the concept of scientific prediction.

Bernie

I also find the conclusions of the paper too tenuous, but I would prefer that someone actually reads the paper and presents a detailed critique.

RobJM

So the current interglacial peaked 2 deg C warmer than today.
The previous interglacial peaked 2 deg C warmer than the current interglacial
But according to climate scientist 2+2=0.5
Of course at the current rate greenland will take 5000 years to melt and as everyone knows the antarctic has been cooling recently, so I guess its up to the computer modellers to come up with an imaginary ice sheet to flood us all!

Barry Elledge

This paper indicates the last previous interglacial lasted 10,000 years. The current interglacial (i.e., the holocene) is already about 12,000 years old, or even older if you think the end of the last glaciation should be marked prior to the Younger-Dryas cold interval. The 19 preceding glaciation events each lasted about 100,00 years in length, 10-15,000 years of which comprise the warm interglacial period. As I interpolate these facts, I necessarily conclude that we are close to the end of the current warm period. Whether the glaciers resume their equatorial advance in 1 year or 3,000 I cannot know, but I am pretty certain that atmospheric CO2 is not going to delay the inevitable by very long, since it never did so in the previous glaciations.
The holocene warm maximum occurred about 8,000 years ago; since then, the long term trend has been to cooler temperatures, with the recently concluded (on geological time scales) Little Ice Age marking the coldest interval since the end of the last glaciation. If we pick the “warmest 5.000 years ” of this interglacial, the period would run from about 9,000 to 4,000 years before present. Unless the warming effects of rising CO2 hit the upper end of the warmist projections, the earth isn’t going to get as warm as it was 8,000 years ago.
So do any readers have a better estimate for how long the holocene is likely to last? In the race between melting Antarctic ice/rising seas and the next ice age, which is likely to come in first?

P.F.

And, of course, here in California, Jerry Brown and his Brown Shirts insist that the rise will be 55 inches in the next 89 years and they are forcing communities to devise climate action plans designed to mitigate a sea level rise of that magnitude.

Sea Level Rising Tax! Coming soon as a withholding to your next pay check….
I think the 3 feet’ers and the 5 meter rise scientists should have to square off and settle this…

nc

Professor Overpeck and student McKay, you guys have to get out more and let the ocean tickle your toes. I have been doing that now and again off the exact same rock for about 55 years.
I wonder if they are aware of this blog? On that theme I wonder if Gore, Susuki, Hansen and others of the same ilk ever drop by and add to the count. Would be interesting to get a debate going, oh silly me there is no debate.

Frank

If this report gets any media traction, ocean front property prices should tank. I think 4000 square feet in Key Largo for $50k would be a good deal.

It’s snowing in New England, Australia, thought I would let you know. Look last glacial period, the sea levels around some continents was as much as 150 metres lower than today. No body lived near the oceans or seas to fish, the Mediterranean was a swamp and lakes, the big melt was gradual, and took thousands of years. I bet you these people who insist on sea levels rising don’t take into consideration that during king tides they come into land more than they do normally. I have a letter from the BOM, forwarded to me by a MP, that the sea levels in Australia
(where exactly it never mention) would rise 177mm by 2050. Yes 6.83 inches. Whose panicking
eh? They are all lying. Corrupting the data to suit their hypothesis. Al Gore bought a house or houses in the areas he predicted they would be swamped. Not very good at predicting the slump
in house prices is he, if his lie were to be believed.

rbateman

Warm the atmosphere AND the oceans?
We don’t have enough fossil fuels to warm the oceans, let alone the atmosphere. We have just enough to warm the inside of most houses during Winter and keep everything else going. That’s why there are all these programs to insulate and be more efficient with the fuels used. When the climate turned cold in the Little Ice Age, the forests were stripped of fuel.
Honestly, the ramblings these Warmists come up with is proof that they don’t even know thier own history.

kbray in california

The Green Governments could bulldoze all the snow and ice into a big pile on North Greenland and on the South Pole.
That might slow the ice from melting, if it really is melting…
We sure don’t want to inconvenience all the poor people in the world who don’t own much to begin with.
It’s really tough on them to move their tent/shack and bedroll a few more feet higher up the beach.
Didn’t Italy deal with a similar water encroachment issue by building canals?
Humans seem to have knack at adapting to changing situations. Deal with it, live with it.

DCC

“The team found that thermal expansion could have contributed no more than 40 centimeters – less than 1.5 feet – to the rising sea levels during that time, which exceeded today’s level up to eight meters or 26 feet.”
What kind of English is that? Intentionally abstruse?
And did he do no research on the possibility that the Bahamas have risen or fallen in that time? It is not a given that the Bahamas are at precisely the same geodetic level today as they were 125,000 years ago.
This paper gives rise to a new phrase: “publish and perish.”

The average depth of the ocean is a bit less than 4,000m.
The expansion coefficient of seawater is probably rather less than 2/10**4 K-1.
The global temperature in the last ice age was around 9 deg C below today’s, but say 10.
So the thermal expansion of the ocean since the last ice age has delivered something like (4000 * (2/10**4) * 10) = 8m of sea-level rise.
The sea level has risen about 120m since the last ice age.
Thermal expansion has therefore accounted for about (8/120) = 7% of the sea level rise since the last ice age.
Now – what was the point of the paper, again?
[but please do check my arithmetic]

noaaprogrammer

Did their models take into acount the affect on the sea level of the landmass rebounding of Greenland and Antartica as they shed their ice sheets?

kadaka (KD Knoebel)

Direct link to paper: pdf
My, Geophysical Research Letters has some interesting things “in press.” For example (bold added):

Kay, J., M. Holland, and A. Jahn (2011),
Inter-annual to multi-decadal Arctic sea ice extent trends in a warming world,
Geophys. Res. Lett., doi:10.1029/2011GL048008, in press.
[PDF] (accepted 8 July 2011)

Simolo, C., M. Brunetti, M. Maugeri, and T. Nanni (2011),
Evolution of extreme temperatures in a warming climate,
Geophys. Res. Lett., doi:10.1029/2011GL048437, in press.
[PDF] (accepted 4 July 2011)

I hear an echo.

Kug, J.-S., and Y.-G. Ham (2011),
Are there two types of La Nina?,
Geophys. Res. Lett., doi:10.1029/2011GL048237, in press.
[PDF] (accepted 6 July 2011)

Lim, Y.-K., and S. D. Schubert (2011),
The impact of ENSO and the Arctic Oscillation on winter temperature extremes in the southeast United States,
Geophys. Res. Lett., doi:10.1029/2011GL048283, in press.
[PDF] (accepted 6 July 2011)

Kim, W., S.-W. Yeh, J.-H. Kim, J.-S. Kug, and M. Kwon (2011),
The unique 2009-2010 El Niño event: A fast phase transition of warm pool El Niño to La Niña,
Geophys. Res. Lett., doi:10.1029/2011GL048521, in press.
[PDF] (accepted 5 July 2011)

Paging Bob Tisdale… He should really like the first one. After all Climate Scientists™ discovered the new and different type of El Nino, the El Nino Modoki. Why not have two types of La Nina as well?

Fu, Q., S. Manabe, and C. Johanson (2011),
On the warming in the tropical upper troposphere: Models versus observations,
Geophys. Res. Lett., doi:10.1029/2011GL048101, in press.
[PDF] (accepted 24 June 2011)

Those (C)AGW-predicting global climate models said there’d be tropical mid-tropospheric hot spots, which we haven’t found. Maybe they were just off a little, and if we look a bit higher…

O’ishi, R., and A. Abe-Ouchi (2011),
Polar amplification in the mid-Holocene derived from dynamical vegetation change with a GCM,
Geophys. Res. Lett., doi:10.1029/2011GL048001, in press.
[PDF] (accepted 8 June 2011)

…say what?
Now THIS looks like the most devious one of the lot. This will require a very thorough examination and dissection.

Maue, R. N. (2011),
Recent historically low global tropical cyclone activity,
Geophys. Res. Lett., doi:10.1029/2011GL047711, in press.
[PDF] (accepted 7 June 2011)

This is clearly deserving of an entire WUWT post to discuss it. At least one.

davidmhoffer

I was reading that the west coast of north america is overdue for an earth quake. I think this explains it.
As the oceans warm, water expands, putting increased pressure on the coastline and keeping it pinned to the rest of the continent. If the warming slows down, who knows what could happen?

Jim Cole

It really galls me to see these mindless “simulations” of drowned coastlines “If sea levels rose to where they were during the Last Interglacial Period”. Cripes, USGS has done the same stupid visualizations
First, any idiot with a set of contour maps could do the same exercise around the kitchen table, but that doesn’t mean it has any predictive value.
Second, what legitimate reason is there to compare today to the last Interglacial 120,000 yrs ago?
Third, the obvious (but unstated) implication of these “simulations” is that the world has been much warmer in the past and sea levels have been much higher – all without any documented elevated CO2. Hmmmmm, howzat Dr. Hansen? Mr. Gore? Kevin? Gavin? Anybody?
When the person in the mirror starts to look like an idiot, the reflection is probably true.

Can’t help wondering when someone will demand a ban on ‘carbonated’ drinks, such as soda water, all forms of fizzy drinks – and beer. But let’s not forget champagne and its lookalikes – they all release vast quantities of CO2 …
OK, I’ll go an be sarcastic somewhere else. The words that grabbed me here were the usual “… by UP TO …” which somehow always get lost in any reporting in the media. Frankly, I don’t think these guys should be awarded the doctorate they are purportedly working for. Not with this study as a report anyway.

Eric Anderson

“The message is that the last time glaciers and ice sheets melted, sea levels rose by more than eight meters. Much of the world’s population lives relatively close to sea level. This is going to have huge impacts, especially on poor countries,” he added.
“If you live a meter above sea level, it’s irrelevant what causes the rise. Whether sea levels are rising for natural reasons or for anthropogenic reasons, you’re still going to be under water sooner or later.”
Am I missing something, or are they using a scare tactic by pointing to an eight meter rise “the last time glaciers and ice sheets melted” and putting out simulation pictures of the last interglacial? No, of course they don’t say that the changes over the next 100 years aren’t nearly that scary, but the scary stories and pictures sure do help get folks charged up emotionally.
Finally, let’s say that things do rise by a meter. How many people actually live a meter above sea level. I know, I know, I’ve seen the estimates: 100M, 146M, etc. Where are these folks. I live relatively close to the coast, have seen numerous beaches all up and down the pacific, have seen thousands of structure, and offhand I’d have a hard time finding a single home that is within 1 meter of sealevel. 10 meters? Yeah. 5 meters? Probably a few. 1 meter? You’d have to be crazy to live near the coast and only one meter above sea level. Forget global warming and sea level rise — a decent storm would wipe you out.
Anyway, I just don’t buy the estimates of all the poor folks who will be wiped out due to a 1 meter rise in sea level — as if that is even realistic over the next 100 years anyway.

I don’t think property prices will tank, people will just get higher stilts for their house. lol. I’m glad to see some REAL data the changes we are told that are so drastic. I could imagine Gore having a heart attack while reading some of these blogs. Keep up the great work!

Dave

I have not yet read the paper, but one thing seems strange: the authors seem to have ignored the effects of long term secular upift of the `last interglacial` shoreline, to say nothing about the huge variability of a visco-elastic earth after the previous glaciation about 160 thousand years ago. There is much debate about this and estimates of the MIS 5e (5.5) sea-level range from 0 m up to 10 m above present. It is time to get real and acknowledge there is huge uncertainty – isn`t that what science is about?

Richard111

“Even though the oceans are absorbing a good deal of the total global warming, the atmosphere is warming faster than the oceans,”
What is it with these people? Is it because they KNOW they will get mass coverage by the media with no questions asked? Or is it because they KNOW they will get lots of money from their illiterate governments? What does that tell you about the world we live in today?
When you consider the first 2.6 metres of the oceans equalls the total mass of the atmosphere above, of course the atmosphere warms faster than the oceans. The top of the atmosphere is exposed to the deepest known cold of the universe. The bottom of the atmosphere is kept warm by the oceans. That is why we are alive and reading and publishing totally stupid statements.

Richard111

Blast! that should have been thermal mass.

“This study marks the strongest case yet made that humans – by warming the atmosphere and oceans – are pushing the Earth’s climate toward the threshold where we will likely be committed to four to six or even more meters of sea level rise in coming centuries.”
Dr Overpeck, this is a totally irresponsible statement. Raising an alarm based on completely unsupported conjecture. If this is the strongest case yet, you’re going to need a good lawyer to “prove” it. Because no scientist can sit here and read your statement and “prove” it. Hell, we can’t even DISprove it, because it has no clear assertion of fact. Pick a number and show the science community how you attempted to test the hypothesis. The bug-eyed writer of this press relaese should also be warned: try a little critical thought!
I am dismayed, as an earth scientist, that this passes as science. What’s more, that it passed peer review.

Evidence for elevated sea levels is scattered all around the globe, he added. On Barbados and the Bahamas, for example, notches cut by waves into the rock six or more meters above the present shoreline have been dated to being 125,000 years old.

I was always under the impression that sea level measurements such as these were “local”, and of course relative to land movements.
Screams of Venice been inundated by rising sea-levels actually turn out to be Venice sinking due to (a) Venusians drawing fossil water from below the city, and (b) a general sinking of the whole basin
So, does this paper actually check to see if these “notches cut by waves” are in to rocks elevated by such things as isostaticand/or techtonic activity?
Just a thought before any credance can be given their selection of proxies.

Eyal Porat

I keep wandering, do they ignore the obvious on purpose or they just have a “blind spot” on this:
According to the elaborate study they presented, in their own words “the new results imply that 4.1 to 5.8 meters, or 13.5 to 19 feet, of sea level rise during the Last Interglacial period was derived from the Antarctic Ice Sheet”. So, the sea was MUCH higher than today. The temps were MUCH higher than today’s.
How on earth do they miss the obvious that these things happen WITHOUT human intervention?
According to their own words, “Based on previous studies, we know that the sea level during the Last Interglacial was up to 8.5 meters higher than today,”.
Then why the hell are we supposed to infer that this time is different? It did happen! It was warmer and the sea WAS higher!
Gosh, I cannot believe I have to spell it out for them.
We are on the verge of a new Ice Age, according to your studies. This is what should bother you, not the warming.

rbateman says:
July 18, 2011 at 9:21 pm
Warm the atmosphere AND the oceans?
We don’t have enough fossil fuels to warm the oceans, let alone the atmosphere.

I think you got that expression bass ackwards. The atmosphere is much lighter and easier to warm than the oceans.
__________

davidmhoffer says:
July 18, 2011 at 10:31 pm
I was reading that the west coast of north america is overdue for an earth quake. I think this explains it.
As the oceans warm, water expands, putting increased pressure on the coastline and keeping it pinned to the rest of the continent. If the warming slows down, who knows what could happen?

Expanded water is lighter, less dense, and the total weight doesn’t change. The distribution of weight moves slightly inland when it expands. If you think that explains anything, good luck working out how!