Posted on 08/16/2004 5:06:16 AM PDT by ckilmer
Ancient Rome's fish pens confirm sea-level fears
09:30 16 August 04
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Coastal fish pens built by the Romans have unexpectedly provided the most accurate record so far of changes in sea level over the past 2000 years. It appears that nearly all the rise in sea level since Roman times has happened in the past 100 years, and is most likely the result of human activity.
Sea-level change is a measure of the relative movement between land and sea surfaces. Tide-gauge records show that the sea level has been rising 1 to 2 millimetres a year since widespread measurements began around 1900, but do not pinpoint when the trend started.
Earlier sea levels can be estimated from geological data, but the accuracy is limited to about half a metre, which is not enough to precisely chart the history of sea-level rise.
So Kurt Lambeck of the Australian National University in Canberra turned to fish pens on the Tyrrhenian coast of Italy for a more accurate record of ancient sea level.
Ice age rebound
The Romans dug these fish pens into bedrock, and the water line in these well-preserved structures shows that the sea level along the Italian coast 2000 years ago was 1.35 metres below today's levels. "They were used for only a very short time, so they make rather nice markers," says Lambeck.
He then analysed how land elevations changed along the Italian coast due to both plate tectonics and the after-effects of the last ice age. In a paper to appear in the journal Earth and Planetary Science Letters, he concludes that geological processes pushed the land up by 1.22 metres over last two millennia, which means that the global sea level rose by 13 centimetres.
That is only about 100 years' worth of rise at the present rate of around 1 to 2 millimetres per year, implying that nearly all of it has occurred since 1900. While there is no proof that human activity is to blame, "I can't think of a natural process that would have started in 1900," he says.
The result "is a significant one", says Jonathan Gregory, who studies global changes in sea level at the University of Reading, UK. The finding supports the idea, based on the few tide-gauge records that extend back two centuries, that the rise in sea level did indeed accelerate about a century ago.
While Gregory cautions that this does not prove that global warming is responsible, both he and Lambeck agree that the results fit the rise in ocean volume expected from global warming melting glaciers in the industrial age.
Jeff Hecht
OK..The world population is around 7 billion. What if we had had no industrial revolution? What if we had maintained the Roman way of life? Can you imagine 7 billion people cutting down trees and burning them to prepare their food, pottery and so on everyday? Can you imagine 7 billion people eliminating into the rivers?
Can you imagine the amount of food in form of game that would be needed to feed all these people?
He then analysed how land elevations changed along the Italian coast due to both plate tectonics and the after-effects of the last ice age. In a paper to appear in the journal Earth and Planetary Science Letters, he concludes that geological processes pushed the land up by 1.22 metres over last two millennia, which means that the global sea level rose by 13 centimetres.
This seems to me to be making an estimate to the nearest ton and then drawing a conclusion based on that estimate to the exact ounce.
"most likely the result of human activity."
Later in this article, it states that there is no proof to support the above. Of course, the 'greenies' have quit reading by then. Climate change is promordial. It's the 'why' part that always gets political, despite the admitted lack of proof.
"More scientific arrogance: "We humans are so frighteningly powerful, we can do things that affect the geologic and astro-physical balance of this fragile little globe we live on. We're making it hotter; we're wiping out forests; we're melting the polar ice caps; we're making the oceans rise, and it's all GEORGE W. BUSH'S fault!!!"
What total crap."
I "mostly" agree. I would like to know who the scientists and environmentalists blame for the dinosaurs extinction, volcano activity back then, the ice age, that HUGE meteor hitting earth like a nuclear bomb back way when. Guess those events where the fault of humans, Bush, Ronald Reagan. I do however blame humans for polluting our rivers and creeks. They are too easy to trash in such short time spans with over development, earth run off and greedy land developers who hook up massive housing track water waste lines to rivers and creeks instead of city water sewer plants.
But how do we explain Sean Penn?
How about sunspot activity and increased solar energy output, which has been measured over the last century as considerably higher than in the past?
Oh, but I forgot....you have an agenda to push. Don't let any scientific facts get in the way. ;)
Most likely? Hasn't this nimrod ever heard of the Little Ice Age, and the warmer period prior to that, that would have affected sea levels?
Its Bush's fault.
True scientific reports include margins of error. I suspect the data is meaningless when the moe is included.
Not since Wilbur Mills and Fanne Foxe were fished out.
Some people go "postal", I tend to go "biblical" on people when I read things like this.
According to scriptures there will be a time when the climate gets hot enough to scorch a man, and the sea levels rise to frightening levels, but according to scriptures, it is because the sun grows brighter and hotter. Not because of any physical thing man is doing to the planet.
It could be that liberals are glomming onto an actual event and attempting to turn it to some political advantage, it could be pure junk science going on and nothing is really changing climate wise. If there is something actually going on, then one can reasonably assume, we may be entering that time foretold when the sun grows hotter.
Hey you SUV drivers! Get out there and put some miles on those puppies. You guys are slacking off.
Here we are in the middle of August in southern Indiana, a time and an area where temps should be in the 90's daytime and 70's night and I'm having to run the blinking furnance to keep warm!!!
We need MORE global warming not less.
Now get in your SUV's and drive!!!
Troy was located on the hill of Hisarlik, which in the Bronze Age overlooked a substantial bay. This provided an excellent anchorage at the mouth of the Dardennelles and was thus a natural site for a substantial town. The bay, however, silted up in late antiquity, which is the primary reason the site of Troy became problematic. With modern mapping techniques to identify the Bronze Age shoreline, the site jumps right out at you.
It appears that nearly all the rise in sea level since Roman times has happened in the past 100 years, and is most likely the result of human activity.That's ridiculous. During the medieval warming period sealevel was higher than it is now (by feet), and has since declined, and hasn't budged.
Someone should ask these "scientists" if a glass of ice water overflows when the ice melts...
Has anyone noticed the Tidal Basin in DC rearing up to swallow the national monuments in the last century ?Well said. There are those who believe that when erosion (from the waves which hit the beach continuously) bring down a seaside home, or a lighthouse, that it's a sign of sealevel rise due to global warming. Those who believe that are stone-cold stupid.
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