Dear James, I got your email. And I decided to ponder your words while I took a break from my studies, as I often do in the afternoon. I felt like sharing my thoughts with you and the entire list.
1. The ocean level is unchanged when floating ice melts. I am a biologist. I got by in chemistry and physics but was never all that great at them. And I've never tried to prove this fact to myself. However= , I did see Mr. Wizard prove this with an experiment using a glass of water and some ice cubes back when I was in junior high. So I am going to take i= t as truth. I would suggest, as others have pointed out, if you're concerned about the inconvenience of sea level rise, it's the ice on land you should pay attention to. 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. I have to disagree with you here. I study marine biology. And I can assur= e you the ocean is not a sphere. I know because I went scuba diving last weekend and I went right to the bottom. If it were a sphere I would have come out the other side instead. Rather, the ocean is a layer on the earth's surface. And the earth is something like a sphere, but the ocean only covers roughly 70% of it's surface. I have never measured this myself. But it's the figure I usually work with. I am a marine biologist and I have never seen figures drastically different so I assume there is a scientific consensus on that. Now the radius of the earth is 6378.15 (according to http://www.factbook.org/wikipedia/en/e/ea/earth_1.html). From my sophomore year in high school I recall that the area of a sphere is 4*pi*r squared. This gave me an approximate surface area of 511209977 square km. 70% of that is 357846984 square km. (I am going to use metric because it's easier for me.) I assumed that was a sphere, because the volume of water needed t= o increase it would be greater than the actual volume since the real ocean is just a shell covering part of a sphere. A sphere with an area of 357846984 has a radius of 5336343 meters. To figure out the volume of water needed to raise the surface 1 meter, I calculated the volume of a sphere with a radius one meter greater, and then subtracted the volume of my first sphere. I calculated this is as 357847000000000 cubic meters of water. I've been to Antarctica. I know there is ice on the land there. Lots of it. I didn't measure it, but according to Wikipedia there is 30000000000000000 cubic meters of ice in Antarctica. I assume that's on land, and not the ice floating or grounded. Given my observation of lots o= f ice in Antarctica I am going to take the Wikipedia figure as truth. Water expands when it freezes so if all that ice melted there would be a smaller volume of water. I don't know how much. Using Archimedes principle on buoyancy, I bet it's about 9/10 as much since I've heard 9/10 of an ice ber= g is under water and the density of an object under water is equal to the density of water it displaces. Given the ice cubes in my gin and tonic tha= t looks about right. I'll take it as truth. Dividing this number by my 1 meter thick layer I get 75.45123. Now of course that doesn't mean 75 meter= s of rise because as the sphere gets bigger it would take more and more water to cover it (But it's not a sphere). But I bet it's enough to still raise the volume of the ocean at least a meter, and probably more. Of course this also assumes that the shoreline is perfectly vertical for at least one meter straight up. Now I know this isn't true because when I wen= t to the beach last weekend, I noticed it sloped very gradually into the water, at least where I was. Nevertheless, I take it as truth that there i= s enough water in Antarctica to raise the ocean a meter or more, maybe several. I am not going to do any more math to prove it to myself. And don't forget Greenland. I don't know if I disagree with your original supposition or not; that thes= e are inconvenient facts. Because, quite frankly, I don't know who you think they're inconvenient for. Well, that's my contribution to the peer review process today. Back to work! Benjamin On 3/21/07, James T. Conklin <[EMAIL PROTECTED]> wrote: > > 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 increas= e > 20 feet, the ocean volume must increase 8,000 times more than for a 1-foo= t > > 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. > --=20 <((((=BA>`=B7.=B8=B8.=B7=B4=AF`=B7.=B8.=B7=B4=AF`=B7...=B8><((((=BA> Ex mari, scientia =B7=B4=AF`=B7.=B8. , . .=B7=B4=AF`=B7.. ><((((=BA>`=B7.=B8=B8.=B7=B4=AF`=B7= .=B8.=B7=B4=AF`=B7...=B8><((((=BA> Benjamin Pister Gentleman, Scholar, Graduate Student Ecology, Behavior, and Evolution Section Division of Biological Sciences University of California, San Diego 9500 Gilman Dr. Mail Code 0116 La Jolla, CA 92093-0116 (858) 822-0633
