Currently, and for some decades past, the oceans have been rising at an average rate of two millimeters per year (Scientific American, 12/02 and 10/03). Two mm equals 0.080in. For a century, at this rate, the worldwide ocean level will rise only 8 inches (100 x 0.080=8.0). For my post (Will Earth get Hotter or Colder), various statement from SA articles were used, to estimate that the maximum rise from now, could be only 20 feet. This is not correct because the amount of ice remaining in the world was more than I thought. The post was based on several statements starting with "10 million cubic miles of ice (9.3 M cubic-miles water) melted after the last ice age raised sea levels by 360-feet". This sounded right. 9.3 million cubic miles water, over 140 million square-miles of ocean, would raise the sea 1/15 of a mile, or 352 feet. Close enough, but I misinterpreted other data.
Statements to reconcile now, include: "Antarctica contains 90% of the remaining ice in the world, and Greenland has most of the rest" (SA). "The West Antarctic ice field contains 3 million cubic kilometers of ice" (SA). A Binghamton University prof, says melting of Greenland's ice cap would cause the sea level to rise 6.6 meters (21.6 feet). Melting all the ice on Antarctica would raise sea level 73.4 meters (241 feet), a total rise of 262 feet.
From these statements, my estimates would be as follows:
262 feet rise over 140 million square miles = 7.0 Million cubic miles water = 7.5 MCM ice.
Antarctica = 90% of 7.5 MCM ice = 6.8 MCM ice
Greenland = 7.5 - 6.8 = 0.7 MCM ice = 0.65 MCM water = 0.65/7.5 X 262 = 22.7-foot rise
West Antarctic Ice Sheet =3 MCKm of ice= 0.72 MCM ice =0.67 MCM water = 23.4-foot rise.
East Antarctic Ice Sheet: 6.8 MCM ice - 0.72 MCM ice (West. Ant.) = 6.1 MCM ice, or 5.7 MCM water. This much water would cause a huge sea level rise. No one is concerned about this, in any human time scale. This ice sheet has been stable for 15 million years, whereas the West Antarctic sheet, has vanished from time to time; the last being 600,000 years ago.
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An interesting post I found about nuclear ships and their potential environmental benefits.
Nuclear Ships of the Cold War
It is interesting, but I believe that ships are only a small part of the energy budget of the world. I really doubt that many will be fueled by nuclear energy, unless the South Africa program to build mini-megawatt, nuclear units for serial production and shipment makes it feasible.
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