WUWT readers may recall yesterday where Dr. Mann was so eager to list this paper on his resume/CV, he broke the embargo set for 15:00 EST June 20th, today, at which time this blog post appears.
As much as this is an editorial target rich environment, I’m going to publish this press release and paper sans any editorial comment. There’s plenty of time for that later. Let’s all just take it in first. Below, figure 2 from the Kemp et al 2011 paper. It should look familiar. Note the reference in Figure 2 to GIA (Glacial Isostatic Adjustment) adjusted sea level data, which has recently been the subject of controversy, it was first noted here on WUWT.
First the press release:
Contact: Evan Lerner
215-573-6604
Penn researchers link fastest sea-level rise in 2 millennia to increasing temperatures
PHILADELPHIA — An international research team including University of Pennsylvania scientists has shown that the rate of sea-level rise along the U.S. Atlantic coast is greater now than at any time in the past 2,000 years and that there is a consistent link between changes in global mean surface temperature and sea level.
The research was conducted by members of the Department of Earth and Environmental Science in Penn’s School of Arts and Science: Benjamin Horton, associate professor and director of the Sea Level Research Laboratory, and postdoctoral fellow Andrew Kemp, now at Yale University’s Climate and Energy Institute.
Their work will be published in the journal Proceedings of the National Academy of Sciences on June 20.
“Sea-level rise is a potentially disastrous outcome of climate change, as rising temperatures melt land-based ice and warm ocean waters,” Horton said.
“Scenarios of future rise are dependent upon understanding the response of sea level to climate changes. Accurate estimates of past sea-level variability provide a context for such projections,” Kemp said.
In the new study, researchers provided the first continuous sea-level reconstruction for the past 2,000 years and compared variations in global temperature to changes in sea level during this time period.
The team found that sea level was relatively stable from 200 B.C. to 1,000 A.D. During a warm climate period beginning in the 11th century known as the Medieval Climate Anomaly, sea level rose by about half a millimeter per year for 400 years. There was then a second period of stable sea level associated with a cooler period, known as the Little Ice Age, which persisted until the late 19th century. Since the late 19th century, however, sea level has risen by more than 2 millimeters per year on average, which is the steepest rate for more than 2,100 years.
To reconstruct sea level, the research team used microfossils called foraminifera preserved in sediment cores from coastal salt marshes in North Carolina. The age of these cores was estimated using radiocarbon dating and several complementary techniques.
To ensure the validity of their approach, the team members confirmed their reconstructions against tide-gauge measurements from North Carolina for the past 80 years and global tide-gauge records for the past 300 years. A second reconstruction from Massachusetts confirmed their findings. The records were also corrected for contributions to sea-level rise made by vertical land movements.
The team’s research shows that the reconstructed changes in sea level during the past millennium are consistent with past global temperatures and can be described using a model relating the rate of sea-level rise to global temperature.
“The data from the past help to calibrate our model and will improve sea-level rise projections under scenarios of future temperature rise,” research team member Stefan Rahmstorf said.
In addition to Horton and Kemp, the research was conducted by Jeffrey Donnelly of the Woods Hole Oceanographic Institution, Michael Mann of Pennsylvania State University, Martin Vermeer of Finland’s Aalto University School of Engineering in Finland and Rahmstorf of Germany’s Potsdam Institute for Climate Impact Research.
Support for this research was provided by the National Science Foundation, the National Oceanic and Atmospheric Administration, United States Geological Survey, the Academy of Finland, the European Science Foundation through European Cooperation in Science and Technology and the University of Pennsylvania.
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Here’s the abstract:
Climate related sea-level variations over the past two millennia
Andrew C. Kempa,b, Benjamin P. Hortona,1, Jeffrey P. Donnellyc, Michael E. Mannd,
Martin Vermeere, and Stefan Rahmstorff
We present new sea-level reconstructions for the past 2100 y based on salt-marsh sedimentary sequences from the US Atlantic coast. The data from North Carolina reveal four phases of persistent sea-level change after correction for glacial isostatic adjustment.
Sea level was stable from at least BC 100 until AD 950. Sea level then increased for 400 y at a rate of 0.6 mm/y, followed by a further period of stable, or slightly falling, sea level that persisted until the late 19th century. Since then, sea level has risen at an average rate of 2.1 mm/y, representing the steepest century-scale increase of the past two millennia. This rate was initiated between AD 1865 and 1892. Using an extended semiempirical modeling approach, we show that these sea-level changes are consistent with global
temperature for at least the past millennium.
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Figure 1: Two points in salt Marshes in North Carolina are used as the basis for the study:
Materials and Methods
Sea level in North Carolina was reconstructed using transfer functions relating the distribution of salt-marsh foraminifera to tidal elevation (7, 12). Application of transfer functions to samples from two cores (at sites 120 km apart) of salt-marsh sediment provided estimates of PME with uncertainties of <0.1 m. For each core a probabilistic age-depth model (10) was developed from composite chronological results and allowed the age of any sample to be estimated with 95% confidence. In Massachusetts, plant macrofossils preserved in salt-marsh sediment overlying a glacial erratic, were dated using AMS 14C and pollen and pollution chronohorizons (Fig. S1). The modern distribution of common salt-marsh plants was used to estimate PME. Sea level was reconstructed by subtracting estimated PME from measured sample altitude. Corrections for GIA were estimated from local (13) and US Atlantic coast (15) databases of late Holocene sea-level index points. Detailed methods are presented in SI Text.
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They compare data at points around the world to the new SL hockey stick (in pink in the background):
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Conclusions
We have presented a unique, high-resolution sea-level reconstruction developed using salt-marsh sediments for the last 2100 y from the US Atlantic coast. Post-AD 1000, these sea-level reconstructions are compatible with reconstructions of global temperature, assuming a linear relation between temperature and the rate of sea-level rise. This consistency mutually reinforces the credibility of the temperature and sea-level reconstructions. According to our analysis, North Carolina sea level was stable
from BC 100 to AD 950. Sea level rose at a rate of 0.6 mm/y from about AD 950 to 1400 as a consequence of Medieval warmth, although there is a difference in timing when compared to other proxy sea-level records. North Carolina and other records show
sea level was stable from AD 1400 until the end of the 19th century due to cooler temperatures associated with the Little Ice Age. A second increase in the rate of sea-level rise occurred around AD 1880–1920; in North Carolina the mean rate of rise was 2.1 mm/y in response to 20th century warming. This historical rate of rise was greater than any other persistent, century-scale trend during the past 2100 y.
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The full paper is available here: PNAS_Kemp-etal_2011_Sea_level_rise
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“Time and Tide wait for no man” is a very old saying.
It’s the 21st Century so it is now “Time, Temperature and Tide wait for no Mann”
Guess that Mikes’ accelerating sea-levels are hiding in the same pipeline as Trenberths’ (The Travesty) missing Heat.
Jeesh Guys, it must be getting a tad over-crowded in there!
They claim that the “change point” for the modern sea level rise was from 1865-1892… But the inflection of the sea level curve actually occurred in ~1800… About 80 years before anthropogenic CO2 emissions started to climb.
Mann’s Sea Level Hockey Stick
Smokey says:
June 20, 2011 at 1:47 pm
Michael Mann grants, 1996 – 2005:
Development of a Northern Hemisphere Gridded Precipitation Dataset Spanning the Past Half Millennium for Analyzing Interannual and Longer-Term Variability in the Monsoons, $250,000
Quantifying the influence of environmental temperature on transmission of vector-borne diseases, $1,884,991
…
This is an incomplete list. For example, there was also the post-Climategate payola grant of $1.6 million to study mosquito vectors. Mann is not an epidemiologist or a biologist. Draw your own conclusions.
It’s second on your list Smokey.
I was asking earlier when we could expect to see that paper.
According to Mann, the Team and Penn State since sea level is accelerating in two locations that it proof it is accelerating.
‘
By that logic, square root is the same as square power:
zero squared equals zero. square root of zero = zero. (sand point)
one square equals one. square root of one = one. (tump point)
Therefore square power = square root
so, like our climate models, we can now can predict the square root of numbers using our new found truth:
power = square root
2 squared is 4, thus we predict:
square root of 2 = 4.
climate science 101.
“The principle reason 300 elite Spartans, 600 Helots, 1,000 Phocians and possibly 2,000 Thebans were able to hold off the Army of Xerxes for three days had as much to do with sea level as it did to the fanatical training of the Spartans.”
Yes — there are actually TWO monuments to the 300. The original is about a mile from the ocean, the new one is closer to the coast road. The sea has withdrawn/the land has risen enough that the site would not make an effective choke point today!
tallbloke lets remember that part of university ‘defense’ of Mann’s work was that he brought in good grant money , what that had to scientific integrate is another question. So these grants are double useful to Mann.
@ur momisugly Latitude
“Yes, they could have included the last decade.
They’ve done it before.
They cherry picked……”
Yes, you are right. I apologise. They only showed 99.95% of the available timeline.
Salt Marshes, like Barrier Islands and Sand Bars, are made out of shifting sand. Someone else needs to look at something more solid and unshifting, like rock maybe. Oh yes, and don’t forget to add in the guessitmated amount of landform rise during the period too, understand that since all the glaciers melted the continents have been growing taller; at least in the far northern hemisphere. Who knew?
I can’t wait for the analyses from McIntyre of this new hockeystick.
Won’t take him long to break this one too, I guess.
My own observations from a place called Hervey Bay on the coast of Australia. Over the course of 50 years, … I see no difference at all.
Same in Vancouver Canada.
You don’t need to study obscure micro fauna to determine the past eights of the oceans, except of course if you are looking to being a fictitious record. British seamen 200 years ago in wooden sailing vessels mapped the oceans to degree of accuracy almost unheard of in present day, because their lives depended on it.
Navigation charts of the ocean from 200 years ago are still accurate as to the heights of drying and submerged rocks, except in area where there have been earthquakes and volcanoes. If there has been any appreciable sea level rise it will be shown in these charts. But it isn’t. These charts are still accurate today.
These are the most accurate records on earth of past sea levels prior to industrialization. The British Admiralty charts. Proof that seal level change is a hoax.
. Litho-, bio-, and chrono-stratigraphy of the Sand Point (A) and Tump Point (B) cores (North Carolina, USA
The data from North Carolina reveal four phases of persistent sea-level change after correction for glacial isostatic adjustment
Sea level was reconstructed by subtracting estimated PME from measured sample altitude.
================================================================================
Sand Point NC is subsiding
Tump Point NC is rising
I would really be interested in seeing how they did that…………..
It seems to me that if you compare the reconstructed NC data to all the other areas sampled, the sea level which forms the backbone of this paper is actually way below average. What this means is that the dramatic upward trend merely brings NC sea levels up par with all the other reconstructed areas.
I live in an area here in Alberta what was once under salt water known as the shallow Western Interior Seaway. Here in oil sands country we often dig up marine mammals dating from approximately 110 million years ago. I’m not far from the Rockey Mountains and I would like to remind Mann if and when I see salt water creeping back into this region that’s when I’m gonna start being delighted with my new beach-front property. Now that’s when I will buy my first sail first boat and install a wharf.
Re ocean hysteria, a nice dissection of Richard ‘UN Parrot’ Black’s latest doomsday piece from the BBC.
“we see Greenpeace’s name up there, steering the research — in its own words — alongside the Pew group, and Friends of the Earth.”
http://www.climate-resistance.org/2011/06/a-deep-sea-mystery.html
And a beautiful piece on following the money from the same site:
“So Friends of the Earth took €3,010,245 from the EU between 2007-9.”
“So the WWF enjoyed gifts of €8,794,595 from the EU. Actually, it got more. It was a joint beneficiary on over €28million euros of EU funds, but I’ve only listed the direct payments from the EU to the WWF.
There’s a lot more. For instance, the Climate Action Network Europe received €1,514,720. in total, then, three searches reveal €13,319,560.”
http://www.climate-resistance.org/2011/06/fun-finding-the-eco-lobbys-funding.html
Anthony, this site deserves a link, methinks.
And another thing – for the geologically challenged like Mann and the Team, there is one certain thing about thick sequences of water saturated soft sediments, such as are found in this North Carolina study:
They compact over time under their own weight – water gets steadily squeezed out of the sediments (the process finally ceases when they become hard rock) – hence they shrink, become less thick – to the goofy this looks like rising sea levels..
In the world of real science – this report would score an F- for cherry picking data and refusing to even consider other possible reasons for ‘the catastrophic ocean rise’.
I make no apologies for referencing this site once again here on WUWT as it gives lie to the myth of global sea-levels rising to catastrophic levels.
http://www.culture24.org.uk/history+%26+heritage/time/roman/art61315
Where the Romans originally landed in England, and where they built their first harbour is now TWO miles inland!
England, along with many other places in the world, is still recovering from the last ice age.The land is going up, the water is going down. I cannot envisage any physical yard-stick being able to differentiate between the two movements.
I’m having a ‘here we go again’ reaction to this paper. When I first got interested in MBH98, I was struck by the contrast between the really messy input data (tree ring widths) and the pristine, clean-room like precision of the output. My initial attention was drawn to two questions (1) how can you measure the width of a tree ring to a claimed precision of 1/10 the diameter of a tree cell, and (2) how can you claim to know that certain trees are suitable temperature proxies and others are not without using post hoc data selection techniques. 12 years later, no one can satisfactorily answer these basic questions.
Now with this new study, Mann and Team claim to be able to measure sea level to sub-millimeter precision using the equivalent of chicken bones and tea leaves and they do so while asserting tight error bars. This is the kind of magic act that leaves competent engineers a bit skeptical. So I’ve got some questions…
I have some fossils of sea creatures I found when hiking and camping in Utah. I found them at an altitude of 6,000 plus feet. Obviously the sea level was much higher when those creatures swam the seas than it is now. Did Mann and friends take that into consideration? When are these so called scientists going to accept the fact that the earth changes, and we have nothing to do with it.
From the press release:
So they did a few reconstructions in North Carolina, confirmed them with a single one done is Massachusetts, which gave them a result for the entire US Atlantic coast, which will be cited as evidence of dangerous global sea level rise, thus proof of dangerous Anthropogenic Global Warming.
I await the consistent calls from the (C)AGW faithful against using regional results to claim global effects, and against “cherry picking” which seems to be broadly defined as looking at particular records instead of the entire record when addressing those presenting evidence against (severe) CO2-caused (C)AGW effects. Yep, they should start rolling in any second now…
It looks like the “North Carolina” series has an inordinate influence on the overall result. Many of the series don’t extend to the medieval warm period, and of those that have extensive data throughout the period only the North Carolina series looks like a Hockey stick. The other series, though more sparse, also appear mixed in terms of agreeing/disagreeing with the Hockey Stick series.
After reading the paper for a second time and the supplemental material once ( http://www.pnas.org/content/suppl/2011/06/14/1015619108.DCSupplemental/pnas.1015619108_SI.pdf ), I failed to see any discussion of correlation factors or r^2 values. Given how Mann has been bitten by his previous misuse of statistics regarding hockey-stick data forms, I would have assumed that he would have at least included this information it the supplemental materials.
(Please let me know if I have accidentally overlooked this information. I did my best, but I’m not a expert.)
Mann is a one stick pony.
It is the same trick. Mann is a one trick pony. The one-trickiness of this is uncanny. This study presents all the same problems as the study behind the hockey stick. The reliability of the proxy is questionable, just as Briffa’s tree rings were questionable. The site selected is highly questionable and there is no justification offered for the selection. (In this case, the site selected is bizarre. If you know that area, you know that the top ten feet have been disturbed regularly.) The main finding flies in the face of history and recent experience, just as the hockey stick did. (If the water level had risen 2 mm per year in this century then my mother would have experienced a rise of 19% of a meter. She is quite capable of conducting a tour to the spots and demonstrating that no such rise took place. For those who have not visited those beaches, a rise of eight inches in sea level would put the foam six to eight feet farther up the gently sloping beach.)
Apparently, Mann and his team are playing the Tar Baby. They expect the same kind of criticism that they received for the original Hockey Stick and they expect to survive that criticism in the same punch drunk, snaggle tooth way once again. Their true believers will stick with them come hell or high water. It seems to me that this is not scientific publication but something entirely different, more akin to theatre, and sceptics are cast in the role of Brer Rabbit. As another pointed out, the presentation is so darned artsy. I think science is not Mann’s calling or goal.
The records were also corrected for contributions to sea-level rise made by vertical land movements.
Does this mean what I think it means? If the data were not behaving properly, they concluded that the land had risen (or fallen)?
Its easy to find fault in other peoples work!
/sarc.