[Greenbuilding] more on ice melt

[Alan Abrams]

so ice cap and sea ice melt *does impact sea level....

from:

http://nsidc.org/news/press/20050801_floatingice.html
Melting of Floating Ice Will Raise Sea Level

When ice on land slides into the ocean, it displaces ocean water and causes
sea level to rise. People believe that when this floating ice melts, water
level doesn’t rise an additional amount because the freshwater ice
displaces the same volume of water as it would contribute once it melts.
Similarly, people also think that when ocean water freezes to form sea ice
and then melts, the water is merely going through a change of state, so it
won’t affect sea level. However, in a visit to NSIDC in May, Dr. Peter
Noerdlinger, a professor at St. Mary’s University in Nova Scotia, Canada,
suggested otherwise.

In a paper titled "The Melting of Floating Ice will Raise the Ocean Level"
submitted to Geophysical Journal International, Noerdlinger demonstrates
that melt water from sea ice and floating ice shelves could add 2.6% more
water to the ocean than the water displaced by the ice, or the equivalent
of approximately 4 centimeters (1.57 inches) of sea-level rise.

The common misconception that floating ice won’t increase sea level when it
melts occurs because the difference in density between fresh water and salt
water is not taken into consideration. Archimedes’ Principle states that an
object immersed in a fluid is buoyed up by a force equal to the weight of
the fluid it displaces. However, Noerdlinger notes that because freshwater
is not as dense as saltwater, freshwater actually has greater volume than
an equivalent weight of saltwater. Thus, when freshwater ice melts in the
ocean, it contributes a greater volume of melt water than it originally
displaced.
-AA

Alan Abrams*
Abrams Design Build LLC*
*design for purposeful living*

6411 Orchard Avenue Suite 102
Takoma Park, MD 20912
office  301-270-NET- ZERO (301-270-6380)
fax      301-270-1466
cell     202-437-8583
alan at abramsdesignbuild.com
www.abramsdesignbuild.com
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