New predictions for sea level rise
Sea level graph from the University of Colorado is shown below:
University of Bristol Press release issued 26 July 2009
Fossil coral data and temperature records derived from ice-core measurements have been used to place better constraints on future sea level rise, and to test sea level projections.
The results are published today in Nature Geoscience and predict that the amount of sea level rise by the end of this century will be between 7- 82 cm (0.22 to 2.69 feet)
– depending on the amount of warming that occurs – a figure similar to that projected by the IPCC report of 2007.
Placing limits on the amount of sea level rise over the next century is one of the most pressing challenges for climate scientists. The uncertainties around different methods to achieve accurate predictions are highly contentious because the response of the Greenland and Antarctic ice sheets to warming is not well understood.
Dr Mark Siddall from the Earth Sciences Department at the University of Bristol, together with colleagues from Switzerland and the US, used fossil coral data and temperature records derived from ice-core measurements to reconstruct sea level fluctuations in response to changing climate for the past 22,000 years, a period that covers the transition from glacial maximum to the warm Holocene interglacial period.
By considering how sea level has responded to temperature since the end of the last glacial period, Siddall and colleagues predict that the amount of sea level rise by the end of this century will be similar to that projected by the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC).
Dr Siddall said: “Given that the two approaches are entirely independent of each other, this result strengthens the confidence with which one may interpret the IPCC results. It is of vital importance that this semi-empirical result, based on a wealth of data from fossil corals, converges so closely with the IPCC estimates.
“Furthermore, as the time constant of the sea level response is 2,900 years, our model indicates that the impact of twentieth-century warming on sea level will continue for many centuries into the future. It will therefore constitute an important component of climate change in the future.”
The IPCC used sophisticated climate models to carry out their analysis, whereas Siddall and colleagues used a simple, conceptual model which is trained to match the sea level changes that have occurred since the end of the last ice age.
The new model explains much of the variability observed over the past 22,000 years and, in response to the minimum (1.1 oC) and maximum (6.4 oC) warming projected for AD 2100 by the IPCC model, this new model predicts, respectively, 7 and 82 cm of sea-level rise by the end of this century. The IPCC model predicted a slightly narrower range of sea level rise – between 18 and 76 cm.
The researchers emphasise that because we will be at least 200 years into a perturbed climate state by the end of this century, the lessons of long-term change in the past may be key to understanding future change.
Please contact Cherry Lewis for further information.
Further information:
The paper: Constraints on future sea-level rise from past sea-level reconstructions. Mark Siddall, Thomas F. Stocker and Peter U. Clark. Nature Geoscience .
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Steve Keohane (08:17:29)
The Ice Caps are Growing By David J. Ameling
http://icecap.us/index.php/go/new-and-cool/the_icecaps_are_growing/
Apr 14, 2008
OK: But
http://pcdsh01.on.br/Imagens/IERSCircularC36_20080704_LeapSecond.JPG
I agree that in general. The planet earth “accelerated” after 1999.
PDO effect?
“Dave: If you have a Russian scientist and an American scientist in collaboration on an important project, you’d better have a very good translator. How many errors of serious consequence would be made in the transition if Americans were ‘forced’ to change from their system to the metric? IOW, two systems in use at the same time. The key, IMO, is to recognize the probability of human error and to diligently search for it.”
1) You do not need a translator; Russian scientists, as well as American scientists, are smart people and both can speak English.
2) American scientists already use the SI (what you call the metric system).
3) As far as I know American cars are metric. So are American spectacles.
4) Other American people should not be forced to change; they should change because it would simplify their life. (Who wants to learn numbers like 43560 or 5280?)
My two ha’p’orth is that metric is better for physics, but for carpentry, cooking &c. imperial has it due to more factors.
Thanks, Fernando. I would suspect that ice accrual at the poles would have a greater effect on rotation than sea level change. I find it interesting that from what I can tell about irrigation by humans is that it can account for over 80% of the sea level rise. So, if the seas are actually rising(slowing rotation), and the earth’s rotation is speeding, there must be a lot of mass going to the poles. Since the arctic ice isn’t growing over the years, the antarctic must be growing.
Steve Keohane (11:16:49) :
Thanks, Fernando. I would suspect that ice accrual at the poles would have a greater effect on rotation than sea level change. I find it interesting that from what I can tell about irrigation by humans is that it can account for over 80% of the sea level rise. So, if the seas are actually rising(slowing rotation), and the earth’s rotation is speeding, there must be a lot of mass going to the poles. Since the arctic ice isn’t growing over the years, the antarctic must be growing.
But we keep adding leap seconds because the Earth’s rotation is slowing down not speeding up.
Alexej Buergin (10:51:36)
1) You do not need a translator; Russian scientists, as well as American scientists, are smart people and both can speak English.
2) American scientists already use the SI (what you call the metric system).
3) As far as I know American cars are metric. So are American spectacles.
4) Other American people should not be forced to change; they should change because it would simplify their life. (Who wants to learn numbers like 43560 or 5280?)
1) Why do they speak English? Romance languages are much easier to learn than either English or Russian. Just ask the French.
2)Except, of course, for some of the American scientists working on the failed Mars probe. It failed because people who’s job it was to check for those kinds of things didn’t.
3)AFAIK, some are, some aren’t, some are a mixed bag.
4)I find it fairly simple to use both systems. Do so on a daily basis.
Steve Keohane
Well,
For this criterion. The Earth’s rotation drags the atmosphere
http://www.cdc.noaa.gov/map/images/reanalysis/aam_total/gleaam.gif
Conclusion crazy:
El Nino: it is condemned to a life short.
Only speculation
“Dave: 1) Why do they speak English? Romance languages are much easier to learn than either English or Russian. Just ask the French.”
Russian is much more complicated than either French or English (my mother gave it a try, but never got anywhere; and it is not just the Cyrillic letters. But my grandfather must have succeded (living in Russia)). French and English are about equally difficult, Spanish more so. But the UK was the greatest power, and that made English the lingua franca.
Phil. (12:16:16) :
“But we keep adding leap seconds because the Earth’s rotation is slowing down not speeding up”
Yes .. We do not discuss this fact.
Only: We are speculating after 1999.
Lingua Franca is the language of the Franks or French.
English is a mongrel not least because under Norman rule the law had to written both in old english and norman french and so was duplicated.
Hence Seize and Detain, Assault and Battery, Cease and Desist, etc.
As for variations in the rotational speed of the earth did you know this was first discovered in the 1930’s with the completion of the Shortt’s clock which was designed to be the most accurate pendulum clock ever built.
Except it ran erratically due to the above variations: atomic clocks don’t really suffer this problem.
Kindest Regards
Alexej Buergin (13:01:57) :
“Prouver que j’ai raison serait accorder que je puis avoir tort.”
Enjoyed the back-and-forth with you.
And now… back to the weather.
Phil. (12:16:16): But we keep adding leap seconds because the Earth’s rotation is slowing down not speeding up.
Not true Phil. It means the ‘day’ as measured by rotation of the earth is slower than the atomic clock, but is less slow since the late 90s. As I originally posted above: “From 1972 thru 1998 (26 years) 21 leap seconds were added. From 1999 to the present (9 years) only 1 leap second has been added.“, and as Fernando posted, one other was added at the end of 2008. So, in 11 years we added 2 seconds vs. 26 years and 21 seconds. Were all things equal, in those 11 years we should have added 8, not 2 seconds. That’s an increase in rotation.
Steve Keohane (20:56:39) :
Phil. (12:16:16): But we keep adding leap seconds because the Earth’s rotation is slowing down not speeding up.
Not true Phil. It means the ‘day’ as measured by rotation of the earth is slower than the atomic clock, but is less slow since the late 90s. As I originally posted above: “From 1972 thru 1998 (26 years) 21 leap seconds were added. From 1999 to the present (9 years) only 1 leap second has been added.“, and as Fernando posted, one other was added at the end of 2008. So, in 11 years we added 2 seconds vs. 26 years and 21 seconds. Were all things equal, in those 11 years we should have added 8, not 2 seconds. That’s an increase in rotation.
No the rotation continues to slow down, just not as rapidly as formerly.
http://upload.wikimedia.org/wikipedia/commons/f/fb/Leapsecond.ut1-utc.svg