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Author Topic: How Much Have Sea Levels Changed Over Time?  (Read 3146 times)

Offline litespeed

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How Much Have Sea Levels Changed Over Time?
« on: 09/12/2009 20:38:38 »
The Copenhagen disaster movie got me to wondering.  How HAVE the ocean levels changed over time?  Any references or opinions?


 

Offline Mazurka

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How Much Have Sea Levels Changed Over Time?
« Reply #1 on: 22/12/2009 14:09:15 »
Where?

local sea level have changed extensively through time.

For example during the last ice age "dogger land" which is now under the North Sea was inhabited (fishermen pull up mammoth bones and flint axes/ arrows as well as peat based paleosols. 

Most major sea level changes will be "eustatic" which relates to the ammount of water avaliable (i.e. sea levels are lower when more water is locked up as ice)

Some sea level rise changes relate to "isostacy" (aka isostatic rebound) which is where land levels change due to loading/ unloading the earths crust by ice.  In the UK, Scotland is going up and the south east is going down (at a rate of mm/yr) as a consequence of the last ice age

There are also "steric" effects which are to do with the expansion of water dictated by temperature/ salinity.

 

 

Offline litespeed

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How Much Have Sea Levels Changed Over Time?
« Reply #2 on: 31/12/2009 19:24:41 »
Mazurka

Thanks for your lucid reply. IMHO, sea levels and land levels both change over time, as you point out. Accordingly, the Copenhagen 'Disaster' movie with the little girl clinging to the last tree branch over a consuming sea might be less then, shall we say, scientific in its content.

IMHO, such presentations reveal a profound failure of intellect, scientific integrity, and even Simple Assed Public Relations. The entire enterprise has become a grotesque parody of it very own self.  For instance, I REALLY REALLY like the Maldavian SCUBA diver in the big fish tank aquarium. A clear and convincing scientific presentation if ever there was one.

I just can't wait to see what Mexico City will bring us. Perhaps giant squid taking down a Spanish Galleon because the sea got warmer.  OOPS. Wrong Millenium.....
« Last Edit: 31/12/2009 19:31:09 by litespeed »
 

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How Much Have Sea Levels Changed Over Time?
« Reply #2 on: 31/12/2009 19:24:41 »

 

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