Catastrophic sea levels 'distinct possibility' this century: study

Apr 15, 2009 by Marlowe Hood
Sunset is seen over the sea. A breakthrough study of fluctuations in sea levels the last time Earth was between ice ages, as it is now, shows that oceans rose some three meters in only decades due to collapsing ice sheets.

A breakthrough study of fluctuations in sea levels the last time Earth was between ice ages, as it is now, shows that oceans rose some three meters in only decades due to collapsing ice sheets.

The findings suggest that such an scenario -- which would redraw coastlines worldwide and unleash colossal human misery -- is "now a distinct possibility within the next 100 years," said lead researcher Paul Blanchon, a geoscientist at Mexico's National University.

The study, published by the science journal Nature, will appear in print Thursday.

Rising ocean water marks are seen by many scientists as the most serious likely consequence of global warming.

The UN Intergovernmental Panel on Climate Change (IPCC) predicted in 2007 that sea levels will rise by up to 59 centimeters (23 inches) before 2100 due simply to the expansion of warmer ocean waters.

This relatively modest increase is already enough to render several small island nations uninhabitable, and to disrupt the lives of tens of millions of people living in low-lying deltas, especially in Asia and Africa.

But more recent studies have sounded alarms about the potential impact of crumbling ice sheets in western and Greenland, which together contain enough frozen water to boost average global sea levels by at least 13 metres (42 feet).

A rapid three-meter rise would devastate dozens of major cities around the globe, including Shanghai, Calcutta, New Orleans, Miami and Dhaka.

"Scientists have tended to assume that sea level reached a maximum during the last interglacial" -- some 120,000 years ago -- "very slowly, over several millennia," Blanchon told AFP by phone.

"What we are saying is 'no, they didn't'."

The new evidence of sudden jumps in marks was uncovered almost by accident at a site in Mexico's Yucatan peninsula that had been excavated for a theme park.

Blanchon and three colleagues from the Leibniz Institute of Marine Science in Germany discovered the remains of coral reefs that made it possible to measure with great precision changes in sea level.

Using contiguous reef crests -- the part of the reef closest to the surface of the water -- as benchmarks, the researchers pinpointed a dramatic jump in sea levels that occurred 121,000 years ago.

"We are looking at a three-metre rise in 50 years," Banchon said. "This is the first evidence that we have for rapid change in sea level during that time."

Only collapsing ice sheets could account for such an abrupt increase, he added.

The last interglacial period, when sea levels peaked six metres higher than current levels, was warmer than the world is today.

But as manmade climate change kicks in, scientists worry that rising temperatures could create a similar environment, triggering a runaway disintegration of the continent-sized ice blocks that are already showing signs of distress.

The recent breakaway of the Wilkins Ice Shelf from the Antarctic peninsula, for example, while not adding itself to sea levels, makes it easier for the glaciers that feed it to flow straight out to sea.

It is still unclear whether this and other dramatic changes seen in ice sheets recently are signs of imminent collapse, or natural processes that have not been observed before.

The Yucatan peninsula is one of only a few regions in the world where the virtual absence of seismic activity over the last several hundred thousand years makes accurate measurements of rise during the last interglacial possible.

"What we have to do now is look at other stable areas, such as western Australia, and confirm the same reef back-jumping signature we found in the Yucatan," said Blanchon.

"Once we have done that, we can say our findings are rock solid."

(c) 2009 AFP

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QubitTamer
3.4 / 5 (14) Apr 15, 2009
All good science until the point where they throw in "But as manmade climate change kicks in..."

Yep, sea levels absolutely rise and fall in response to climate change, and there is good geological evidence, well studied and peer-reviewed that shows that sea level rise and fall can be quite large over relatively short periods of time.

So the question becomes, will the people living in those low-lying areas build massive levees or will they move?

For an example of how a sea level drop affected a major urban center in recent times, see the historical record of the Roman city of Ostia Antica...
http://en.wikiped...al_site)
lengould100
2.7 / 5 (9) Apr 15, 2009
Interesting. Keep up the great research, people.
Azpod
3.4 / 5 (13) Apr 15, 2009
Of course they ignore all the evidence that the Earth hasn't warmed in the last decade or so and may in fact be starting a cooling tread.

When will people learn that geometric curves don't exist in nature... even when you factor in our playing with it? Either it levels off (as our population curve, recently considered to be geometric, is going to do) or it follows a cycle (as the climate does.)

Anytime you take recent trends and project them out 100 years, of course you're going to see disaster looming.
lengould100
3.8 / 5 (4) Apr 15, 2009
QubitTamer: Given that eg. the entire palace of Cleopatra at mouth on Nile is now underwater it seems a stretch to assume that "Ostia now 3 km from sea" is entirely due to sealevel dropping and not either silting of Tiber or plate movements due to earthquakes etc.

"The 1998 campaign of underwater investigations on the Lighthouse has lead us to think, together with geophysicists, about the constitution of this site; apparently, subsidence is particularly strong in this region %u2013 from 5 to 7 m since Antiquity. "

http://www.unesco...lex6.htm
MorituriMax
2.7 / 5 (14) Apr 15, 2009
Amazing, and all this happened before humans had any major effect on the environment through SUVs, coal burning plants, etc. 121,000 years ago? Major jumps in sea levels? Who was doing this, Atlantis?
GrayMouser
4.2 / 5 (5) Apr 15, 2009
Didn't they recently find the remains of a town off the coast of Spain in around 100 feet of water?

Additionally, what is the probability behind the statement "now a distinct possibility within the next 100 years"? What is the chance, based off of what factors, and with what error ranges? Or is this just somebody's opinion?
Fazer
4.3 / 5 (6) Apr 15, 2009
Nothing wrong with research, and this is good stuff to know, if it is confirmed, but it bothers me when I see these automatic assumptions about AGW casually thrown into articles.

If it weren't for "manmade climate change" kicking in, the unspoken suggestion seems to be that it might NOT get as hot during this interglacial period, and we would all remain safely high and dry.

Why?

We hear all kinds of complicated explanations about how we are causing global warming/climate change, but very little speculation about why we have glacial fluctuations at all.

If the primary cause is orbital eccentricities, wouldn't that be a pretty simple, straight forward set of calculations? I mean orbital dynamics is a solidly understood science, so is it possible to predict these eccentricities the same way we predict cometary orbits, etc?
jeffsaunders
4.3 / 5 (4) Apr 16, 2009
Fazer,
You are right - orbital eccentricities are well known math. Since nobody has noticed this, I conclude that the global warming seen recently is not caused by eccentricities. I could be putting too much faith in the people that normally do these measurements but I do not have the tools to do the math myself.

That leaves a lot of things that can change the climate, including solar eccentricities which cannot be measured as well as orbits. All we can do is go off measurements made over the last few decades where reliable equipment has been recording these measurements.

We can jump to conclusions without reliable data but it is not really science then, it is speculation.
dachpyarvile
3.4 / 5 (5) Apr 16, 2009
Just over 120,000 years ago sea level was on the order of several meters higher than it now is. Mankind did not load CO2 into the atmosphere at that time. Several places along the coasts of the Mediterranean are subject to geological phenomena and there are numerous techtonic platelets in the entire region.

They just had to throw in the alarmist crap, now didn't they? No one is talking about what could happen to the majority of the continental United States should there be changes in the magma-water ratio under the southwestern region.

The environment will not cause this. It could just happen. Should it do so, most of the western United States as well as most of the Great Plains will be submerged under meters of water. Bet if it happened the alarmists will blame CO2 for it. :)
John_balls
2.7 / 5 (7) Apr 16, 2009
You right wingers are so funny (:
QubitTamer
3 / 5 (10) Apr 16, 2009
And there he is, Johnballs... crawling out from under his soft fuzzy blanket of stupdity and group-think to peep out some kind of non-sequitur.

Funny how he assumes we are all right wingers. I guess anyone who thinks, observes, and forms their own opinions based on empirical data and non-politicized research is a right-winger to him. Ironic that it's people like him, driven by fear and hatred of other people that are always the tools of the real right wingers and other facists. If Johnballs was living in 1930's Germany i am sure he would believe everything Hitler said about Jews and he would attack anyone who dissented. If he lived in Stalinist Russia during the purges he would be turning in his neighbors to the NKVD if they didn't parrot everything the Commisars said. It's the ignorant masses like Johnballs who are the tools of the fear-mongers and hate-spreaders like Al Gore and all of the pathetic little men who came before him that have caused humanity such grief over the centuries.
Velanarris
3.7 / 5 (6) Apr 16, 2009
And there he is, Johnballs... crawling out from under his soft fuzzy blanket of stupdity and group-think to peep out some kind of non-sequitur.

Funny how he assumes we are all right wingers. I guess anyone who thinks, observes, and forms their own opinions based on empirical data and non-politicized research is a right-winger to him. Ironic that it's people like him, driven by fear and hatred of other people that are always the tools of the real right wingers and other facists. If Johnballs was living in 1930's Germany i am sure he would believe everything Hitler said about Jews and he would attack anyone who dissented. If he lived in Stalinist Russia during the purges he would be turning in his neighbors to the NKVD if they didn't parrot everything the Commisars said. It's the ignorant masses like Johnballs who are the tools of the fear-mongers and hate-spreaders like Al Gore and all of the pathetic little men who came before him that have caused humanity such grief over the centuries.

Couldn't say it better myself.
iamcrazy
2.3 / 5 (3) Apr 16, 2009
my plans are in motion. the chloride ion rockets are working! very soon... ahahahahahahahahahahh
docknowledge
4.3 / 5 (3) Apr 16, 2009
All the politically correct right-wingers, please stand to that side. All the left-wingers, the other side. Everyone else, in the middle: there's plenty of space there.
GrayMouser
5 / 5 (1) Apr 17, 2009
That leaves a lot of things that can change the climate, including solar eccentricities which cannot be measured as well as orbits. All we can do is go off measurements made over the last few decades where reliable equipment has been recording these measurements.



We can jump to conclusions without reliable data but it is not really science then, it is speculation.

http://scienceand...tter.pdf
John_balls
1 / 5 (3) Apr 17, 2009
Ahhh , my fans love me.
John_balls
2.3 / 5 (3) Apr 17, 2009
And there he is, Johnballs... crawling out from under his soft fuzzy blanket of stupdity and group-think to peep out some kind of non-sequitur.



Funny how he assumes we are all right wingers. I guess anyone who thinks, observes, and forms their own opinions based on empirical data and non-politicized research is a right-winger to him. Ironic that it's people like him, driven by fear and hatred of other people that are always the tools of the real right wingers and other facists. If Johnballs was living in 1930's Germany i am sure he would believe everything Hitler said about Jews and he would attack anyone who dissented. If he lived in Stalinist Russia during the purges he would be turning in his neighbors to the NKVD if they didn't parrot everything the Commisars said. It's the ignorant masses like Johnballs who are the tools of the fear-mongers and hate-spreaders like Al Gore and all of the pathetic little men who came before him that have caused humanity such grief over the centuries.

See I knew you were a right wing extremist , you could not help but bash Al gore.

I don't listen to a person, a sky god etc. I listen to peer reviewed science. Try it some day and you will learn something.

While your at it please post your own scientific work so that it may be peer reviewed. Oh ..your not a climatologist??



Velanarris
5 / 5 (3) Apr 18, 2009
While your at it please post your own scientific work so that it may be peer reviewed. Oh ..your not a climatologist??


Interesting John, very interesting. What are Hansen and Manns' degrees in? Oh yeah, Physics.
thorn
1 / 5 (4) Apr 19, 2009
SUV and coal pollution are extremely beneficial for human baby and infant lungs, so let's have more of it. Yeah, smart. Anyway. I'm almost 40 and I wonder to this day if the possibility exists that I will see Antarctica in my lifetime. I mean the continant and islands under the ice. Would the stronger nations that lost land want to take some back from this new continant? Would the land have any use or workabillity being dark a good chunk of the year? If no seeds are found frozen and intact how long would it take for plants to adapt? Will I still be in good enough shape to hike one of the islands? Ahh the future, one can only imagine.
dachpyarvile
5 / 5 (2) Apr 19, 2009
SUV and coal pollution are extremely beneficial for human baby and infant lungs, so let's have more of it. Yeah, smart.


No, particulates from pollution are bad and we should limit those. On the other hand, CO2 is nothing to worry yourself about. When it rises to above 7000 ppm that would be the time to worry. (Millions of years before man walked the earth, CO2 levels were that high).

Coal technology in the US is much cleaner than that now. I'd be worrying more about diesel and biodiesel, however. These fuels produce more particulates that are harmful to infants and other people.

SUVs are not a problem. The fuels they use are a problem. But, chemicals used to produce and maintain solar arrays have their own ill effects, including up to 17000 times the radiative forcing of CO2.

Anyway. I'm almost 40 and I wonder to this day if the possibility exists that I will see Antarctica in my lifetime. I mean the continant and islands under the ice.


Well, what are you waiting for? Go to Antarctica and quit whining about not going. Will Antarctica be there in the next forty years with ice? Certainly. That will not be changing anytime soon contra AlGo and the Obamamessiah. The only thing that will de-ice Antarctica would be for the ocean currents to stop flowing around the continent. 55 million years ago Antartica was a pine-forest. Millions of years before that it was a tropical climate.

Would the stronger nations that lost land want to take some back from this new continant?


I doubt it.

Would the land have any use or workabillity being dark a good chunk of the year?


Probably. As I said above, Antarctia was once a pine-forest with varied forms of life now extinct.

If no seeds are found frozen and intact how long would it take for plants to adapt?


There already are plants living there in the form of certain grasses. There are also algaes and so forth, as well as various species of insects. It would not take long in the geological schema of things, I imagine.

Will I still be in good enough shape to hike one of the islands?


Who knows? If you sit on your rear-end all the time believing AlGo, probably not. But, in the end it does not matter since Antarctica will not be de-icing anytime soon.

Ahh the future, one can only imagine.


There seems to be a lot of imaginary science that passes for legitimate science of late so you go right on imagining as you have been deceived into imagining. I, on the other hand, will just keep on waiting for some legitimate science that is not falsifiable in the place of the "computer models" that nowadays leave much to the imagination...

But, you can stop imagining an Antarctica without ice in your lifetime. That will not happen until the ocean currents are stopped by continental drift.
Nartoon
3.7 / 5 (3) Apr 20, 2009
Someone please tell these scientists that it's impossible to measure a 50 year trace on something that covers 120,000 years. They'd be lucky if they could narrow it down to which 1,000 years, never mind 50 years.
Yahya
1 / 5 (2) Apr 20, 2009
Research I've done in 2004 studding solar radiation received by earth that goes back to 200 years ago and global carbon output shows a very strong correlation between emission rates of Co2 and the increase in earth's average temperature. From the start of the research I excluded changes in earth's orbit as it have no effect on solar radiations received by earth, that's as far as I remember its been a while since I looked into that paper.

Anyway, there is no real evidence that the three meter change in sea level is global unless they find the same trend in different regions. For all we know it could be just plate tectonics in play.

Velanarris
5 / 5 (2) Apr 20, 2009
From the start of the research I excluded changes in earth's orbit as it have no effect on solar radiations received by earth
Priceless.
GrayMouser
5 / 5 (1) Apr 20, 2009
Fazer,

You are right - orbital eccentricities are well known math. Since nobody has noticed this, I conclude that the global warming seen recently is not caused by eccentricities.

Actually, the math has been done and there appears to be a correlation (http://icecap.us/...AGE.doc) but this has been poo-pooed by the AGW crowd (they never debate it, just ignore it.)
Fazer
4 / 5 (2) Apr 21, 2009
Nothing wrong with research, and this is good stuff to know, if it is confirmed, but it bothers me when I see these automatic assumptions about AGW casually thrown into articles.



If it weren't for "manmade climate change" kicking in, the unspoken suggestion seems to be that it might NOT get as hot during this interglacial period, and we would all remain safely high and dry.



Why?



We hear all kinds of complicated explanations about how we are causing global warming/climate change, but very little speculation about why we have glacial fluctuations at all.



If the primary cause is orbital eccentricities, wouldn't that be a pretty simple, straight forward set of calculations? I mean orbital dynamics is a solidly understood science, so is it possible to predict these eccentricities the same way we predict cometary orbits, etc?


Now cross-reference this article with another story about atmospheric lead causing more cloud cover:

http://www.physor...515.html

Could coal burning and use of leaded gasoline have masked a natural warming trend. Over the last two decades, lead levels have dropped, I think, and now we are wide open for the warming to continue toward levels similar to the last interglacial.

Just food for thought, if anyone is interested.

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