From the University of Haifa via Eurekalert
The sea level has been rising and falling over the last 2,500 years
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  IMAGE: Rising and falling sea levels over relatively short periods do not indicate long-term trends. An assessment of hundreds and thousands of years shows that what seems an irregular phenomenon today…
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“Rising and falling sea levels over relatively short periods do not indicate long-term trends. An assessment of hundreds and thousands of years shows that what seems an irregular phenomenon today is in fact nothing new,” explains Dr. Dorit Sivan, who supervised the research.*
The sea level in Israel has been rising and falling over the past 2,500 years, with a one-meter difference between the highest and lowest levels, most of the time below the present-day level. This has been shown in a new study supervised by Dr. Dorit Sivan, Head of the Department of Maritime Civilizations at the University of Haifa. “Rises and falls in sea level over relatively short periods do not testify to a long-term trend. It is early yet to conclude from the short-term increases in sea level that this is a set course that will not take a change in direction,” explains Dr. Sivan.
The rising sea level is one of the phenomena that have most influence on humankind: the rising sea not only floods the littoral regions but also causes underground water salinization, flooded effluents, accelerated coastal destruction, and other damage.
According to Dr. Sivan, the changing sea level can be attributed to three main causes: the global cause – the volume of water in the ocean, which mirrors the mass of ice sheets and is related to global warming or cooling; the regional cause – vertical movement of the earth’s surface, which is usually related to the pressure placed on the surface by the ice; and the local cause – vertical tectonic activity. Seeing as Israel is not close to former ice caps and the tectonic activity along the Mediterranean coast is negligible over these periods, it can be concluded that drastic changes in Israel’s sea levels are mainly related to changes in the volume of water.
In the present study, in light of earlier studies, research student Ayelet Toker and Dr. Sivan, set out to examine Israel’s sea level over the past 2,500 years, based on data deduced from many coastal archaeological findings. They made a careful selection of findings that have been reliably and accurately dated, and first focused on findings that were excavated by the Antiquities Authority in Acre of the Crusader period. These revealed that the sea level during the Crusader period – just 800 years ago – was some 50-90 centimeters lower than the present sea level. Findings from the same period at Caesarea and Atlit reinforced this conclusion. When additional sites were examined from periods before and after the Crusader period, it was revealed that there have been significant fluctuations in sea level: During the Hellenistic period, the sea level was about 1.6 meters lower than its present level; during the Roman era the level was almost similar to today’s; the level began to drop again during the ancient Muslim period, and continued dropping to reach the same level as it was during the Crusader period; but within about 500 years it rose again, and reached some 25 centimeters lower than today’s level at the beginning of the 18th century.
“Over the past century, we have witnessed the sea level in Israel fluctuating with almost 19 centimeters between the highest and lowest levels. Over the past 50 years Israel’s mean sea level rise is 5.5 centimeters, but there have also been periods when it rose by 10 centimeters over 10 years. That said, even acute ups and downs over short periods do not testify to long-term trends. An observation of the sea levels over hundreds and thousands of years shows that what seems a phenomenon today is as a matter of fact “nothing new under the sun”, Dr. Sivan concludes.
SteveE (04:34:53) :
Where did you get that 26% from? The national geographic put it at half:
http://news.nationalgeographic.com/news/2001/08/0829_wiredutch.html
Wikipedia puts it at 20% althought the reference is to a Dutch document so I can’t tell if it’s correct.
To quibble, that is not from “National Geographic” but is actually a Christian Science Monitor piece.
From AFP:
One would expect the Dutch authorities to know their own country better than “National Geographic,” the IPCC, or even the supremely authoritative Wikipedia. But then again, one would expect “IPCC experts” to be able to do proper math as well.
This is old news. Rhoades Fairbridge studied the sea levels years ago and demonstrated sea level changes of several meters over relatively short time periods. He also predicted the current cooling and increased earthquakes and vulcanism. Of course it’s taboo to discuss his theories on this site.
I wonder about sea level in Roman Times. The docks at Ostia Antiqua and Pompey are a long way from the ocean today as is the pass at Thermopylae defended by the Spartans against the Persians.
NASA breathing new life into old assessments, backtracking from CO2 doctrine?
Yes, our sun is a variable star!!!!!
http://science.nasa.gov/headlines/y2010/05feb_sdo.htm?list1010788
About those charts of the Netherlands, the flooded area would be around 26-27% but its based on NAP (Normaal Amsterdams Peil) wich on itself is not correct because that is based on the high tides in the former Zuyderzee, wich is now the “IJsselmeer” east of Amsterdam, the high tides there where higher than those along the coast of the Netherlands.
I doubt that IPCC has checked if those figures are based on the real sealevels or on the NAP, anyway a figure of 50% completely out of range.
Another thing, sealevel rise, i live close to Hoek of Holland where the sealevel has risen 19 cm between 1888 and 1995, an average of just 1,7 mm a year. Up north in the town of Harlingen (where i was born) its just 13 cm over the same period, an average rise of 1.21 mm a year.
We might be vituperative, but at least we don’t mess with the numbers (and with the tree ring[s](Briffa, you know why i made the “s” optional)).
“kwik (22:49:06) :
[…]
Or it will be called MaldiveGate…..;
http://www.climatechangefacts.info/ClimateChangeDocuments/NilsAxelMornerinterview.pdf
”
This very elegant argument by Dr. Nils-Axel Mörner was completely unknown to me, stunningly elegant, about sea level rise:
“There’s another way of
checking it, because if the radius of the Earth increases, because
sea level is rising, then immediately the Earth’s rate of
rotation would slow down. That is a physical law, right? You
have it in figure-skating: when they rotate very fast, the arms
are close to the body; and then when they increase the radius,
by putting out their arms, they stop by themselves. So
you can look at the rotation and the same comes up: Yes, it
might be 1.1 mm per year, but absolutely not more.”
Fantastic.
SteveE (04:34:53) :
“ScientistForTruth (03:17:30) :
The real figure for Netherlands territory below sea level is 26%, so AR4 has it more than double. AR4 is looking like a joke a minute!
Where did you get that 26% from? The national geographic put it at half:”
National Geographic is as rubbish a source as IPCC – it’s an advocacy magazine now. I exposed it as such here http://buythetruth.wordpress.com/2009/06/02/world-food-supplies-and-carbon-emissions/
Currently, the Dutch consider that 20% of land below sea level is about right as a round figure. The figure changes because more land is being reclaimed. As far as the IPCC is concerned, giving them the benefit of a few years before 2007, they could have checked official government statistics from CBS (Central Bureau of Statistics, “Statistics Netherlands”), which in their Statistical Yearbook of the Netherlands 2004, page 451, gives the figure as 24%.
http://www.cbs.nl/NR/rdonlyres/3C60B3E9-09E0-491F-87F2-99B8E54936A1/0/2004a3pub.pdf
Of course, what else is wrong with the part I quoted is that it takes the Netherlands as a classic example: “The Netherlands is an example of a country highly susceptible to both sea-level rise and river flooding…”
But this is what the Dutch government has to say in “Sustainability Monitor for the Netherlands 2009”
http://www.cbs.nl/NR/rdonlyres/A36109C6-85F5-4371-8625-9D504C7DF957/0/2009sustainabilitymonitorofthenetherlandspub.pdf
“It its 2006 climate scenarios, the Royal Netherlands Meteorological Institute (KNMI) predicts that sea levels along the Dutch coast may rise by 35 to 85 centimetres. This is larger than the global average rise foreseen by the IPCC. Current technology enables the Dutch to reinforce its shore protection systems at socially acceptable costs (MNP, 2007b), even if the rate of sea level rise increases to 1.5 metres per century as a result of the increasing melting rates of the large land ice caps.
…The Netherlands will probably be able to withstand climate change and rising sea levels for a number of centuries to come. The safety of the country appears to be guaranteed to 2100 with respect to rising sea levels and river drainage. Even in the worst-case sea level rise of 1.5 metres per century, flooding will be able to be prevented with existing technology (reinforcing and raising dykes, at a cost of a maximum of 0.15 percent of GDP).”
Highly susceptible, my foot – it can easily withstand sea level rise FOR CENTURIES at moderate cost and existing technology – i.e. it’s business as normal for the Dutch. Looks like Glaciergate all over again. What is in the IPCC report is a lie, and a cruel hoax.
It seems to me reading the press release and many of the comments following that what we are looking at is a combination of several things. At the end of the last major glaciation when the ice sheets withdrew from the middle latitudes to the high latitudes the sea level rose due to run off from the melting ice on land. It appears that we are still seeing rising sea levels due to rising earth mass due to decompression with the loss of ice weight on the land mass. If the land mass rises the area of the dry land increases and this would force the sea into a smaller surface area which would cause a rise in sea levels where the land mass isn’t rising. Water doesn’t compress so it has to go somewhere so it rises. Perhaps this would explain some of the variability noted in the article over the past several thousand years. cooler periods the level drops warmer periods it rises. The amounts we are speaking of in recent recorded history are not unusual when put in perspective to the events before recorded history in the geological past. With the capabilities we have now we should be able to cope with any changes coming down the pike if our governments will focus on adaption rather than prevention. I am sure we can adapt. I am not so sure we can change or prevent climate variation.
Bill Derryberry
Can anyone help me reconcile these two statements from the article?
1. “The sea level in Israel has been rising and falling over the past 2,500 years, with a *one-meter* difference between the highest and lowest levels…”
2. “During the Hellenistic period, the sea level was about *1.6 meters* lower than its present level…”
Stacey (05:40:05) :
Wikipedia has a nice article on it.
http://en.wikipedia.org/wiki/Post-glacial_rebound
It’s a proccess where the land rises up after removing the weight of ice sheets from the last ice age. It’s effects can be seen over the Northern Europe and America.
What about the level of the GROUND above the sea level?, this changes too with plate tectonics.
Off topic but file under way too funny but Mann’s off the hook in fine politico fashion
RA-10 Inquiry Report: Concerning the Allegations of Research Misconduct
Against Dr. Michael E. Mann, Department of Meteorology,
College of Earth and Mineral Sciences,
The Pennsylvania State University:
Under The Pennsylvania State University’s policy, Research Administration Policy No. 10, (hereafter referred to as RA-10), Research Misconduct is defined as:
(1) fabrication, falsification, plagiarism or other practices that seriously deviate from accepted practices within the academic community for proposing, conducting, or reporting research or other scholarly activities;
(2) callous disregard for requirements that ensure the protection of researchers, human participants, or the public; or for ensuring the welfare of laboratory animals;
(3) failure to disclose significant financial and business interest as defined by Penn State Policy RA20, Individual Conflict of Interest;
(4) failure to comply with other applicable legal requirements governing research or other scholarly activities.
RA-10 further provides that “research misconduct does not include disputes regarding honest error or honest differences in interpretations or judgments of data, and is not intended to resolve bona fide scientific disagreement or debate.”
They might as well be lauding his having been cleared of practicing Wicca and also having passed the urine test for anabolic steroids. He’ll keep his gold medal in “flinging fiction” it seems.
Some tectonic plates movements (rising and sinking continents):
South American plate: moving relatively westward at 10 cm/year
Nazca plate: moving relatively eastward at 15 to 17 cm/year
Antarctic plate:seems to be moving generally away from the eastern hemisphere (Indian-Australian and Pacific plates) at 5 to 9 cm/year, with additional spreading from South America and the south Atlantic at 1.5 to 2 cm/year
http://jersey.uoregon.edu/~mstrick/AskGeoMan/geoQuerry29.html
Why would the size of the Strait of Gibraltar make any diff to the level of the Med?
I have 2 dams next to each other on my property connected via a small channel. If I narrowed the channel, all it would do is increase the speed of water flow. Unless I made it so narrow that the quantity of water transfer is exceeded by the amount I take out of the 2nd dam.
i.e In the case of the Med and Strait of Gib, the amount evaporating from the surface of the Med would have to exceed the amount flowing in (faster) from the Atlantic.
Somehow I don’t think Gibraltar is an issue here.
I looked into sea-level rise in the Med a while back, provoked by the claim in tv prog that the Nile Delta was being flooded by rising sea level.
The Nile Delta is in fact subsiding because of the absence of the annual deposit of silt that was ended with the building of the Aswan Dam upstream in 1970.
Change in sea-level in the Med also varies from West to East and is highest in the Eastern basin where Israel is located and is less apparent in the Adriatic or Balearics, for example.
I do not understand the author’s dismissal of volcanic/tectonic activity in the region. The Med is a very active volcanic region and subject to many earthquakes. Sounds like Israel has been going up and down like a see-saw historically. This tells us nothing about the change in the volume of water sloshing around in the earth’s oceans.
I recall a paper that was published some seven or eight years ago that mentioned the sea of Galilee was likely to have surface ice some 2000 years ago. The author hinted that the cold conditions then may have led to the story of Jesus walking on water. I contacted the author, mentioning that his study was consistent with the Holocene sea level work of Rhodes Fairbridge. He appreciated the confirmation, but lamented the nasty letters and emails he was getting (for obvious reasons).
Going further back during the Eeminan Interglacial, a paper published two years ago reported the first evidence of human culture at a cave at Es Skhul (near present day Haifa). Back then, the sea was only a few hundred meters from the mouth of the cave system. Now the sea shore is several kilometers away.
We have a lot of warming to go through before we get to the natural limits documented over time, particularly in that area.
Damn that Israeli Oil Lobby!
From the article:
Anybody been contacted?
/Mr Lynn
http://www.breitbart.com/article.php?id=CNG.8d6e5773c60565dfc6e882b0a8dcbf18.4e1&show_article=1
Netherlands is asking for clarification on how 50% of their country risks floooding form sea level rise when only 26% if below sea level…
Kum Dollison (03:19:57) :
This guy, Gerald Marsh, says that it isn’t CO2, or the Milankovitch Cycles that cause the Glacials/Interglacials, but Galactic Cosmic Rays.
http://arxiv.org/ftp/arxiv/papers/1002/1002.0597.pdf
Wow … this deserves a thread of its own. If this is verified it completely resets several climate theories, not the least of which is CO2=AGW.
Andrew30 (20:59:20) :
“Seeing as Israel is not close to former ice caps and the tectonic activity along the Mediterranean coast is negligible over these periods, it can be concluded that drastic changes in Israel’s sea levels are mainly related to changes in the volume of water.”
Given that the entire Mediterranean sea has dried up completely at least twice and perhaps event three times in the past the as the Strait of Gibraltar opened and closed, that comment about the “negligible” “tectonic activity” could be a bit of confirmation bias. These drying periods have been proven by drilling and retrieving core samples, including thick salt pan layers, from under the deepest parts of Mediterranean Sea. …
I may be missing your point, but the Strait of Gibraltar did not close or open in the sense that a sluice gate does, but rather sea level fell until water could no longer pass over the shallow sill. This cut off the flow of water into the Mediterranean from the Atlantic. It is a situation like the communication between the Mediterranean and the Black Sea.
However, I paused at the statement that there is no tectonic activity along the Mediterranean coast over such period. The region is obviously tectonically active — perhaps little occurs over a period of a thousand years (like the Central U.S.), but I’d need some convincing that the coast of Israel remains stable just the same.
The block quote feature is so aggravating at times…
I may be missing your point, but the Strait of Gibraltar did not close or open in the sense that a sluice gate does, but rather sea level fell until water could no longer pass over the shallow sill. This cut off the flow of water into the Mediterranean from the Atlantic. It is a situation like the communication between the Mediterranean and the Black Sea.
However, I paused at the statement that there is no tectonic activity along the Mediterranean coast over such period. The region is obviously tectonically active — perhaps little occurs over a period of a thousand years (like the Central U.S.), but I’d need some convincing that the coast of Israel remains stable just the same.
Interesting that sea levels, global mean temperature, glacier length, Arctic ice area and any other climate metric you care to name are all either going up or down over time and are never stable. But within this maelstrom of change there are tantalising quasi-cyclical periods of order and stability which stay until turbulence raises it’s head.
Looks like Edward Lorenz was right back in the early 60’s when he stated that climate was driven by deterministic chaos and would always be unpredictable.
Seems that climate science has forgotten this simple fact, but still postures and struts to the tune of our corrupt politicians. Sad.
“Seeing as Israel is not close to former ice caps and the tectonic activity along the Mediterranean coast is negligible over these periods, it can be concluded that drastic changes in Israel’s sea levels are mainly related to changes in the volume of water”
I echo another poster on that one: to neglect the senestral movement over 2,500y along the 1,200km NS transform Dead Sea fault seems quite a rich proposal. Slip rate is 4.9mm/y +- 1.4 for the past 6 years, not negligible imo.
Read: 2008 Le Béon M., Y. Klinger, A. Amrat, A. Agnon, L. Dorbath, G. Baer, J-C. Ruegg, O. Charade and O. Mayyas (2008), Slip rate and locking depth from GPS profiles across the southern Dead Sea Transform, J. Geophys. Res., Vol. 113, B11403, doi:10.1029/2007JB005280