Significant sea-level rise in a 2-degree warming world

Jun 24, 2012

The study is the first to give a comprehensive projection for this long perspective, based on observed sea-level rise over the past millennium, as well as on scenarios for future greenhouse-gas emissions.

" is a hard to quantify, yet critical risk of climate change," says Michiel Schaeffer of Climate Analytics and Wageningen University, lead author of the study. "Due to the long time it takes for the world's ice and to react to global warming, our emissions today determine sea levels for centuries to come."

Limiting global warming could considerably reduce sea-level rise

While the findings suggest that even at relatively low levels of global warming the world will have to face significant rise, the study also demonstrates the benefits of reducing greenhouse-gas emissions. Limiting global warming to below 1.5 degrees Celsius and subsequent temperature reductions could halve sea-level rise by 2300, compared to a 2-degree scenario. If temperatures are allowed to rise by 3 degrees, the expected sea-level rise could range between 2 and 5 metres, with the best estimate being at 3.5 metres.

The potential impacts are significant. "As an example, for New York City it has been shown that one metre of sea level rise could raise the frequency of severe flooding from once per century to once every three years," says Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research, co-author of the study. Also, low lying deltaic countries like Bangladesh and many small island states are likely to be severely affected.

Sea-level rise rate defines the time for adaptation

The scientists further assessed the rate of sea-level rise. The warmer the climate gets, the faster the sea level climbs. " have less time to adapt if sea-levels rise faster," Rahmstorf says.

"In our projections, a constant level of 2-degree warming will sustain rates of sea-level rise twice as high as observed today, until well after 2300," adds Schaeffer, "but much deeper emission reductions seem able to achieve a strong slow-down, or even a stabilization of sea level over that time frame."

Building on data from the past

Previous multi-century projections of sea-level rise reviewed by the Intergovernmental Panel on (IPCC) were limited to the rise caused by thermal expansion of the ocean water as it heats up, which the IPCC found could reach up to a metre by 2300. However, this estimate did not include the potentially larger effect of melting ice, and research exploring this effect has considerably advanced in the last few years. The new study is using a complementary approach, called semi-empirical, that is based on using the connection between observed temperature and sea level during past centuries in order to estimate sea-level rise for scenarios of future .

"Of course it remains open how far the close link between temperature and global sea level found for the past will carry on into the future," says Rahmstorf. "Despite the uncertainty we still have about future sea level, from a risk perspective our approach provides at least plausible, and relevant, estimates."

Explore further: Mystery solved: 'Sailing stones' of death valley seen in action for the first time

Provided by Potsdam Institute for Climate Impact Research (PIK)

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User comments : 36

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NotParker
2.2 / 5 (24) Jun 24, 2012
The AR5 crescendo. Bad paper after bad paper released hoping to ensure grant money.
Vendicar_Decarian
3.3 / 5 (22) Jun 24, 2012
ParkerTard doens't seem to like the idea that the ocean will continue to warm past the year 2100. Apparently he thinks it will stop at that date for some magical reason.

In any case, a warmer ocean means a bigger ocean as any child can tell you.

Unless that Child is ParkerTard, UbvonTard, or sunshinehour1, or any of ParkerTard's other alternate identities.

He is mentally diseased, and needs to get immediate psychiatric help.
A2G
3.7 / 5 (20) Jun 24, 2012
VD your attack on NotParker was child like. You are the one you needs to get immediate psychiatric help, that is if you are not already seeking professional help.

The way in which you present yourself currently will never enable you to get the point you are making to your intended audience, unless that is the same crowd that worships "South Park"

Why don't you just try and stick to the point of your argument instead of your personal attacks. You are making your side look really bad in most peoples eyes who would read what you just wrote.

Vendicar_Decarian
3 / 5 (17) Jun 24, 2012
There was no attack. Simply a stating of facts.

"VD your attack on NotParker was child like" - A2G

If you also think that ocean heating and expansion will magically halt at year 2100 you are equally ignorant and diseased.
Daniel_Bennigan_s
3 / 5 (12) Jun 24, 2012
I don't see why there is so much debate over this issue. The fact is, the Earth and the universe for that matter all act in a cyclical manner. Eventually the Earth will be much warmer and the oceans will be much higher. Eventually this country will be nothing but history and a new society will begin like it has occurred many times before. Thinking that human beings will halt the progression of nature is foolish.
Vendicar_Decarian
3.6 / 5 (14) Jun 24, 2012
Absolutely. I agree with Daniel. Nothing matters, since we are all dead men anyway. So let's just burn, rape, pillage, and murder for everything is a meaningless, pointless cycle.

Morality is pointless.
R James
2.6 / 5 (12) Jun 25, 2012
Can we see the same for a 1 degC cooling, which is just as likely.
Vendicar_Decarian
3.5 / 5 (13) Jun 25, 2012
If you ignore physics and abandon reality then you are right. 1'C cooling is possible.

The impossible IS possible at http://www.zombo.com/

"Can we see the same for a 1 degC cooling" - R-Tard
GSwift7
2.6 / 5 (7) Jun 25, 2012
If you ignore physics and abandon reality then you are right. 1'C cooling is possible.


The article above is talking about risk assessment and emergency planning. In that context, I have to agree with you; that there's no practical need to plan for a global temperature decrease.

However, the need for coastal adaptation and planning in the face of increasing sea level isn't up for discussion. I don't know how it is done in other countries, but here in the US the Corps of Engineers cooperates with local and state coastal and urban planning boards and emergency management boards and insurance companies. There are already detailed plans for just about every inch of US coastline regarding sea level rise. Those plans influence decisions about zoning, road building, beach and wetland management, river management, fresh water use, port dredging, and the list goes on and on.

So, we're already prepared and it's not like we have our heads in the sand you know.
GSwift7
2.3 / 5 (6) Jun 25, 2012
As always, when there are discussions about global average sea level change, I would like to point out that local change happens much faster than global change. Local change over shorter periods of time makes slow global change in sea level almost irrelevant. Global change can't be ignored, but it's so slow compared to all the other changes that it's an afterthought in terms of planning and risk management.

For example, continental drift is happening at a rate between 1 and 10 cm per year. That's up to nearly 5 inches per YEAR. Parts of the coast of Chile were raised by 3 meters in just a few minutes in the 2010 earthquake. The state of Florida is a particularly good example of how complicated it can be, and why the rate of local change dwarfs the rate of global sea level change. The following paper from the US Geological Survey is quite good:

http://pubs.usgs....ades.pdf

Other places will have completely different problems.
NotParker
2.2 / 5 (10) Jun 25, 2012
If you ignore physics and abandon reality then you are right. 1'C cooling is possible.


The article above is talking about risk assessment and emergency planning. In that context, I have to agree with you; that there's no practical need to plan for a global temperature decrease.


Sure there is.

Step #1 Tell people it is possible and it is happening in various regions.

Step #2 Tell people, like farmers, not to count on warmer weather.

For example, Washington State. Last 5 years colder by 1.1F than previous 5 years.

http://sunshineho...omalies/

And as cold as the early 1900s.
rubberman
3.2 / 5 (9) Jun 25, 2012

"Step #1 Tell people it is possible and it is happening in various regions."

You are a prime example of why telling people with a predisposed mindset is a futile waste of time.

"Step #2 Tell people, like farmers, not to count on warmer weather."

Predictions based on.....what exactly?

"For example, Washington State. Last 5 years colder by 1.1F than previous 5 years"

Or you can compare pre 1980 to post 1980 and cherry pick the other way.....

http://www.appins..._usa.htm

NotParker
2.1 / 5 (11) Jun 25, 2012

"Step #1 Tell people it is possible and it is happening in various regions."

You are a prime example of why telling people with a predisposed mindset is a futile waste of time.

"Step #2 Tell people, like farmers, not to count on warmer weather."

Predictions based on.....what exactly?

"For example, Washington State. Last 5 years colder by 1.1F than previous 5 years"

Or you can compare pre 1980 to post 1980 and cherry pick the other way.....

http://www.appins..._usa.htm



The graphs you show do show that the last 5 years are colder then the first 5 years of the 1900s. But they try and obscure it.

Pick the bar chart.

http://www.ncdc.n.../wa.html

rubberman
3.9 / 5 (7) Jun 25, 2012
"The graphs you show do show that the last 5 years are colder then the first 5 years of the 1900s. But they try and obscure it."

They show a general warming trend since 1980, I told you that I was cherry picking THAT data. Pay attention.
NotParker
2.1 / 5 (11) Jun 25, 2012
"The graphs you show do show that the last 5 years are colder then the first 5 years of the 1900s. But they try and obscure it."

They show a general warming trend since 1980, I told you that I was cherry picking THAT data. Pay attention.


-0.38 degF / Decade from 1986 to 2011.

Climate changes. Cycles go from warming to cooling.

25 years of cooling.

Trends change.

Cooler than the early 1900s.
R James
2.1 / 5 (11) Jun 25, 2012
If you ignore physics and abandon reality then you are right. 1'C cooling is possible.

Strange - if I accept the reality that there's been no warming for the past 15 years, then cooling seams very possible. If I accept the physics of cloud density, or the Pacific Decadal Oscillation, then cooling is very likely. What we're being fed by the media is based on cherry picked physics, and incomplete computer models.
vlaaing peerd
2.6 / 5 (8) Jun 26, 2012
that's going to be a nice challenge, I live 22 metres below sea level. We just finished the Deltaworks some 15 years ago and we're looking at another /-75 cm rise in the next 50 years. May not sound like much but over here it's recipe for disaster.
Instead of putting another few billion on the taxpayer's tab, I think we should US and China pay for at least a part of it :P We still didn't get any money for making New Orleans watertight, so seems fair enough.
rubberman
3.4 / 5 (10) Jun 26, 2012
that's going to be a nice challenge, I live 22 metres below sea level. We just finished the Deltaworks some 15 years ago and we're looking at another /-75 cm rise in the next 50 years. May not sound like much but over here it's recipe for disaster.
Instead of putting another few billion on the taxpayer's tab, I think we should US and China pay for at least a part of it :P We still didn't get any money for making New Orleans watertight, so seems fair enough.


THis type of observational fact has no place here. They want to talk about Washington state, not places where the effects of climate change are already undeniable, observed and documented.
Howhot
3.5 / 5 (8) Jun 26, 2012
You know, its not just thermal expansion of the oceans that is causing sea level rise. There is also the massive amounts of Arctic Greenland Ice and Antarctic Ice that will be melting for the next 100 years. And the Himalayan and Rocky mountain glaciers, lets not forget. There are many factors in the rapid and devastating sea level rise expected.

Fools that dismiss this as weather are fools themselves. I expect a full two meters sooner. 1 meter by 2050; easy.

I also expect massive forest fires this year as a drought (caused by burning fossil fuels) takes a grip on the mid-USA.
NotParker
1.9 / 5 (9) Jun 26, 2012
You know, its not just thermal expansion of the oceans that is causing sea level rise. There is also the massive amounts of Arctic Greenland Ice and Antarctic Ice that will be melting for the next 100 years.


Nope.

"Twenty-year-old models which have suggested serious ice loss in the eastern Antarctic have been compared with reality for the first time - and found to be wrong, so much so that it now appears that no ice is being lost at all."

http://thegwpf.or...how.html
Howhot
4 / 5 (8) Jun 26, 2012
You know Nopark (he hates parks btw) that would be great if it was true.
http://www.nasa.g...oss.html
Vendicar_Decarian
3.7 / 5 (7) Jun 27, 2012
Concerning ParkerTard's source for that claim...

In mid-April 2011, the GWPF provided "900 Peer-Reviewed Papers Supporting Skepticism Of "Man-Made" Global Warming (AGW) Alarm".[18] The blog Carbon Brief analyzed them, and found that -
9 of the top 10 authors had ties to ExxonMobil
"prominent scientists featured on the list didn't agree that their work supported skepticism about anthropogenic global warming - and had unsuccessfully asked for their work to be removed from similar lists in the past", and
the most-cited journal was Energy and Environment, a journal with a very low impact factor whose editors are AGW deniers

More can be found here...

http://www.source...undation

"Twenty-year-old models which have suggested serious ice loss in the eastern Antarctic" - Parkertard
Vendicar_Decarian
4.3 / 5 (6) Jun 27, 2012
One of the interesting things about physics, is that you really can't cherry pick it.

CO2 absorbs IR that principally comes from below, and re-radiates it in all directions - hence some back downward.

It follow from that simple fact that increasing CO2 to the atmosphere necessarily heats the atmosphere below.

R-James and the other denialists are doing their very best to un-know that inescapable truth.

To that end they whine about socialism, one world governments, conspiracies, and a large list of other irrelevancies that can not in any way alter the radiative physics of CO2.

"What we're being fed by the media is based on cherry picked physics" - R-James
Vendicar_Decarian
3.7 / 5 (7) Jun 27, 2012
ParkerTard's latest lie is easy to expose.

http://www.woodfo...88/trend

Hmmm. Looks like an increase in temperature from 0.15'C to 0.55'C to me.

Perhaps ParkerTard is looking at the graph while standing on his head.

"25 years of cooling." - ParkerTard
Vendicar_Decarian
3.5 / 5 (8) Jun 27, 2012
The latest lie told by (ParkerTard = UbVonTard = sunshinedays1)
is easy to expose...

http://www.woodfo...00/trend

Looks like a warming from -0.42'C to 0.4'C = 0.82'C to me.

One wonders why ParkerTard continually repeats the same lies over and over again.

"Cooler than the early 1900s." - ParkerTard

He is clearly suffering from some mental disease.
NotParker
1.4 / 5 (7) Jun 27, 2012
The latest lie told by (ParkerTard = UbVonTard = sunshinedays1)
is easy to expose...

http://www.woodfo...00/trend

Looks like a warming from -0.42'C to 0.4'C = 0.82'C to me.


http://i47.tinypi...5ykp.jpg

Colder than 1944.
NotParker
1.6 / 5 (7) Jun 27, 2012


http://www.source...undation

"Twenty-year-old models which have suggested serious ice loss in the eastern Antarctic" - Parkertard


According to a statement from the American Geophysical Union, announcing the new research:

It turns out that past studies, which were based on computer models without any direct data for comparison or guidance, overestimate the water temperatures and extent of melting beneath the Fimbul Ice Shelf. This has led to the misconception, Hattermann said, that the ice shelf is losing mass at a faster rate than it is gaining mass, leading to an overall loss of mass.

The teams results show that water temperatures are far lower than computer models predicted ...

http://www.thereg...melting/
Vendicar_Decarian
3.9 / 5 (7) Jun 27, 2012
ParkerTard's latest lie is easy to expose.

He is comparing "summer" temps in 1945 to "winter" temps in 2010.

His plot uses monthly data, as shown by the following plot from the same source.

http://www.woodfo.../to:1946

The maximum appears at year 1945.6 which is mid North America Summer. The peak is 0.38'C.

He then compares the temperature to the minimum shown in 2010, which is expanded here.

http://www.woodfo...rom:2010

The minimum corresponds to North American Winter, with a temperature of 0.33'C.

The difference is 0.05'C.

The maximum "summer" temperature in 1945 is only 0.05'C warmer than the minimum "winter" temperature in 2010.

Of course the earth has no "summer" and "winter" seasons but since land mass dominates the NH, it's seasons bias global temps.

"Colder than 1944." - ParkerTard

Poor dishonest ParkerTard. Caught lying again.

He is mentally diseased.
Vendicar_Decarian
3.7 / 5 (7) Jun 27, 2012
Poor ParkerTard. Now he is caught yammering nonsense about trivially irrelevant model limitations.

The Fimbul Ice Shelf is an ice shelf about 120 miles (200 km) long and 60 miles (100 km) wide. As such it constitutes 1/25,000th of the earth's surface, or 0.0039%.

ParkerTard/UbvonTard/sunshinehours1 is mentally diseased. He needs go get help immediately before he starts to hurt himself or others.

Ocean circulation models are not as well developed as atmospheric models, and they need not be to establish the extent at which the atmosphere is warming.

"Computer models... overestimate the water temperatures and extent of melting beneath the Fimbul Ice Shelf." - ParkerTard
NotParker
1.5 / 5 (8) Jun 27, 2012
Poor ParkerTard. Now he is caught yammering nonsense about trivially irrelevant model limitations.

The Fimbul Ice Shelf is an ice shelf about 120 miles (200 km) long and 60 miles (100 km) wide. As such it constitutes 1/25,000th of the earth's surface, or 0.0039%.

ParkerTard/UbvonTard/sunshinehours1 is mentally diseased. He needs go get help immediately before he starts to hurt himself or others.

Ocean circulation models are not as well developed as atmospheric models, and they need not be to establish the extent at which the atmosphere is warming.

"Computer models... overestimate the water temperatures and extent of melting beneath the Fimbul Ice Shelf." - ParkerTard


Thanks for the laugh.

You should get help.

Admittedly you do more to discredit greenies than anyone on the planet.
Vendicar_Decarian
4 / 5 (9) Jun 27, 2012
The Fimbul Ice Shelf is an ice shelf about 120 miles (200 km) long and 60 miles (100 km) wide. As such it constitutes 1/25,000th of the earth's surface, or 0.0039%.

For some reason ParkerTard think that is immensely significant.

His mental disease causes him to laugh when it is shown that it is entirely insignificant on a global scale.

R James
2.3 / 5 (7) Jun 28, 2012
VD - I see you're looking at the revised Hadcrut data. Up until a couple of months ago, it was quite different, but they needed more warming. They found some previously ignored data from the Northern Hemisphere that they added to boost the recent temperatures (they wouldn't do the same for the Southern Hemisphere because it would go the other way). In good science, if they hypothesis doesn't fit the data, then they change the hypothesis. To the amazement of the scientific world, they changed the data.

If you want to check this, a quick google search will give you the details.

Looking at the plot, take out the straight line, so you can see it clearly. There has probably been an overall increase in recent times - it's expected as we come out of the little ice age. However, this is a graph over a very short time period - about 100 years. You can see a cycling of temperature, and if I had the predict the next decade, I'd certainly say we're coming into cooling period.
Vendicar_Decarian
4 / 5 (8) Jun 28, 2012
That is interesting because other denialists have been defending their use of Hadcrut3 rather than 4, because they claim, it has no significant difference from Hadcrut3.

Why can't you denialists make up your minds?

"VD - I see you're looking at the revised Hadcrut data. Up until a couple of months ago, it was quite different." - R Tard
Vendicar_Decarian
4 / 5 (8) Jun 28, 2012
You are right. Hadcrut3 omitted large regions around the poles - simply ignoring the regions and assuming they didn't exist.

Now they have filled in most of those regions with temperature data.

By not including the regions in their original time series, they biased their record lower that it should have been. And that is why Denialists such as yourself chronically used Hadcrut3 rather than GISS or NOAA.

When this was pointed out to you, you claimed it wasn't true.

Now you admit that it was, and by so doing expose your earlier lie.

"They found some previously ignored data from the Northern Hemisphere that they added to boost the recent temperatures" - R_Tard

Thanx for playing R-Tard.
NotParker
1.8 / 5 (5) Jun 29, 2012
According to a statement from the American Geophysical Union, announcing the new research:

It turns out that past studies, which were based on computer models without any direct data for comparison or guidance, overestimate the water temperatures and extent of melting beneath the Fimbul Ice Shelf. This has led to the misconception, Hattermann said, that the ice shelf is losing mass at a faster rate than it is gaining mass, leading to an overall loss of mass.

The teams results show that water temperatures are far lower than computer models predicted ...
R James
2.3 / 5 (3) Jun 30, 2012
One of the interesting things about physics, is that you really can't cherry pick it.

CO2 absorbs IR that principally comes from below, and re-radiates it in all directions - hence some back downward.

It follow from that simple fact that increasing CO2 to the atmosphere necessarily heats the atmosphere below.

R-James and the other denialists are doing their very best to un-know that inescapable truth.

"What we're being fed by the media is based on cherry picked physics" - R-James

Actually, you are cherry picking it. You ignored the fact that the effect from CO2 is logarithmic - doubling the CO2 doesn't double the effect. For example, if you paint a window black, it stops most of the light. If you paint another coat, it makes little difference. The direct CO2 effect is about 1.2 degC only. I'm happy to debate indirect effects if your science knowledge is up to it - after all, it's the indirect effects that the hypothesis of catastrophic warming is based on.