"1.  The ocean level is unchanged when floating ice melts."

But if that floating ice originated on land, like pieces of the Greenland or 
Antarctic ice shelves, then the sea level would go up when that ice was added 
to the ocean (and eventually melted). In addition, melting glaciers and 
continental ice sheets do raise the level of the ocean. Ice bergs don't 
typically originate as floating ice. 

"2.  The ocean is a spherical body of water.  The ocean volume varies as
the cube of the ocean radius.  Therefore, for the ocean radius to increase
20 feet, the ocean volume must increase 8,000 times more than for a 1-foot
radius increase.  For the ocean radius to increase 40 feet, the ocean
volume must increase 64,000 times more than for a 1-foot radius increase."

This seems to attempt to downplay the possibility of rising sea level. Sea 
level has risen some 400 feet since the end of the last ice age, a magnitude 
twenty times greater than the twenty-foot increase you hypothesize here. 
Granted, current ice volumes are a fraction of that of Pleistocene glaciation, 
but taking average estimates of just the Antarctic ice sheet (at approximately 
30 million square km) and the Greenland ice sheet (3 million square km) and 
ignoring mountain glaciers, a 20-foot sea-level rise doesn't seem too 
far-fetched, regardless of the volumetric mechanics. 

In addition, thermal expansion of water as the oceans warm would contribute to 
a measurable amount of sea level rise. The sea level has risen 1-3mm/year in 
the last 100 years, and it is believed that thermal expansion is responsible 
for at least as much if not more of that warming. 

Cheers,

.j.

************************
Jacquelyn Gill
Graduate Research Assistant
Jack Williams Lab

University of Wisconsin - Madison
Department of Geography
550 North Park St.
Madison, WI 53706

608.890.1188 (phone)
608.265.9331 (fax)

----- Original Message -----
From: "James T. Conklin" <[EMAIL PROTECTED]>
Date: Wednesday, March 21, 2007 5:42 pm
Subject: [ECOLOG-L] Ocean Level Rising
To: [email protected]

> Inconvenient Facts  regarding rising ocean level:
> 
> 1.  The ocean level is unchanged when floating ice melts.
> 
> 2.  The ocean is a spherical body of water.  The ocean volume varies 
> as 
> the cube of the ocean radius.  Therefore, for the ocean radius to 
> increase 
> 20 feet, the ocean volume must increase 8,000 times more than for a 
> 1-foot 
> radius increase.  For the ocean radius to increase 40 feet, the ocean 
> 
> volume must increase 64,000 times more than for a 1-foot radius increase.

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