Skip to comments.Sea Levels are Never Still
Posted on 06/18/2014 6:36:50 AM PDT by SeekAndFind
Sea levels have been rising and falling without any help from humans for as long as Earths oceans have existed.
The fastest and most alarming sea changes to affect mankind occurred at the end of the Pleistocene Ice Age. Seas rose about 130m about 12,000 years ago, at times rising at five metres per century. Sea levels then fell as ice sheet and glaciers grew in the recent Little Ice Age some Roman ports used during the Roman Warm Era are now far from the sea even though sea levels have recovered somewhat during the Modern Warm Era.
Many natural factors cause sea levels to rise - melting of land-based glaciers and ice sheets; warming and expansion in volume of the oceans; extraction of groundwater which ends up in the oceans; and sediments, sewerage, plant debris and volcanic ash washed into the oceans by rivers, storms and glaciers. In addition, tectonic forces cause some blocks of land to rise while others fall, hence the paradox of sea levels appearing to rise on one coastline while falling on another.
Currently the worlds oceans are rising at about 1mm per year, which has not changed much with the great industrialisation since 1945. Amongst all the factors moving the restless sea, mans production of carbon dioxide is obviously an insignificant player.
Sea levels are always changing, at times very destructively. Waves move sea levels by a few metres and at places like Derby, WA, king tides can move sea levels by eleven metres. Then there are rogue waves up to 30 metres high which have sunk oil tankers, and tsunamis which can smash coastlines with a ten metre wall of water moving at over 800 km per hour.
(Excerpt) Read more at americanthinker.com ...
there are many recent finds of houses and cities under 10-20 meters of water
These are ANCIENT cities and must be from a very long time ago when sea levels where that much lower
if you look at the Atlentic ocean, it alwasy seemed odd to me that the Atlantic Shelf went out so far and then suddenly dropped off... It looked like the sea level was at that point for a long long time and then rose ... 20 meters
Giving us our current shoreline
tides do not go offshore for miles and miles
Take a look at the Atlantic shelf and tell me if it does not look like the ancient shoreline was at a way lower sea level? worn away for millions of years...
Today, Venice is a city in northeastern Italy sited on a group of 118 small islands separated by canals and linked by bridges to the mainland and each other.
Moon and sun gravity effects are not limited just to coastal regions.
Ground levels also rise and fall. Subduction zones push up mountains. Rift valleys drop and widen as the continents are stretched. The Himalayan mountains rise a couple feet a year.
As it say’s in Ecclesiastes the rivers run into the sea but the sea never fills.
I think thats been around awhile.
Venice has always been built on islands in a marsh. It’s why they built the city there.
Too wet for armies, and too shallow for navies.
That’s why they remained unconquered for well over a thousand years.
There was an interesting article in National Geographic not so many years ago which, on one hand, was pushing global warming with "Venice is about to become a victim!" theme while on the other, outlined the long history of the city with its centuries old ebb and flow of reclaiming land from the oceans and marshlands when the city prospered to letting nature reclaim parts of the city when it did not.
Makes one wonder how someone able to document that long historical perspective can also shill for the Chicken Littles who claim global warming is a recent man-made crisis.
Sorry, but “Venice” usually refers to the city, not its various possessions, which at different times have been scattered over much of the eastern Med coastlines and islands and northern Italy.
As I understand it, the site of the Battle of Thermopylae (think “300”) is now several miles inland. At the time of the battle in the Persian Wars, around 480 BC , the site was bordered by the Straits of Eubora. In fact, many of Xerxes’ elephants (and men) were reportedly driven off the cliffs into the sea.
So much for “rising sea levels.”
But in Venice, circa 1600, the areas on the mainland around the lagoon were considered part of Venice in much the same way that the west end or east end or southside are considered part of London even if they are well outside of "The City", or original walled area founded by the Romans.
Not today, of course, since for the most part they are no longer there. Venice has been a shrinking city since about 1750, probably earlier. And it had more to do with economics (the decline of the Venetian Empire as a trade center) than it had to do with industrialization, rising sea levels and the like.
Still don't believe it? Look at exactly the reverse situation in the Netherlands/Belgium. Before 1600, they were colonies of Spain and economic backwaters. Once they became economic trade centers, they reclaimed land from the sea exactly as Venice had done during its peak, albeit with more modern technology.
Sorry, but the Netherlands were at the very center of the European economy from the early Middle Ages on. Most of the great cloth manufacturing centers were there. The axis of the European country was from northern Italy to the Netherlands.
The great wealth of the area was precisely why they were able to fight off the Spanish Empire, the greatest in the world at the time and supported by the looted wealth of Mexico and Peru, for 80 years.
The result of the war was partition of the Netherlands, with the still Spanish-controlled and Catholic segment (later Belgium) indeed becoming an economic backwater for a century or two. While the independent and Protestant section became the wealthiest country on earth for a time.
Charles V, under whom the rift started, was raised in the Netherlands and much more a Netherlander than a Spaniard.
I believe it is generally believed that the land under and around Venice is sinking, largely due to excessive pumping from the fresh water aquifer underlying the area.
As opposed to the sea rising.
As you yourself pointed out, the real rise begin with the partition of the Netherlands and Belgium and the Netherlands, as a bastion of religious liberty, greatly surpassed Belgium within a century of that partition.
The influx of Huguenots with their industry and inventiveness deserves no small part of the credit for that transformation.
Call me naive, but as VAST as our oceans are, I couldn’t imagine even melting ALL of the ice on the planet moving the sea levels all THAT much. I think it would be about like dumping a typically sized bag of ice into a near full bathtub.
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