Comments on: We’ve trashed the land in our search for electricity; let’s trash the oceans next http://blogs.law.harvard.edu/philg/2008/11/30/weve-trashed-the-land-in-our-search-for-electricity-lets-trash-the-oceans-next/ A posting every day; an interesting idea every three months... Sun, 29 Nov 2009 03:22:04 -0500 http://wordpress.org/?v=2.8.4 hourly 1 By: Jan Fure http://blogs.law.harvard.edu/philg/2008/11/30/weve-trashed-the-land-in-our-search-for-electricity-lets-trash-the-oceans-next/comment-page-1/#comment-94590 Jan Fure Tue, 02 Dec 2008 23:11:54 +0000 http://blogs.law.harvard.edu/philg/?p=1143#comment-94590 Sho: The water stored at high altitude in a dam might be at most a few kilometers farther away from the spin axis of the earth than other water at the same latitude. Water stored at 60 degrees latitude is more than 3300 kilometers closer to the earth’s spin axis than ocean water at the equator. I think the directions of the rivers that are dammed are irrelevant, as the water would in all cases reach the ocean, either directly, or through evaporation in cases like the Dead Sea and the Great Salt Lake. Sho: The water stored at high altitude in a dam might be at most a few kilometers farther away from the spin axis of the earth than other water at the same latitude. Water stored at 60 degrees latitude is more than 3300 kilometers closer to the earth’s spin axis than ocean water at the equator.

I think the directions of the rivers that are dammed are irrelevant, as the water would in all cases reach the ocean, either directly, or through evaporation in cases like the Dead Sea and the Great Salt Lake.

]]> By: Sho http://blogs.law.harvard.edu/philg/2008/11/30/weve-trashed-the-land-in-our-search-for-electricity-lets-trash-the-oceans-next/comment-page-1/#comment-94551 Sho Tue, 02 Dec 2008 04:19:22 +0000 http://blogs.law.harvard.edu/philg/?p=1143#comment-94551 Yes, but water flows towards the centre of gravity first, any other direction second. Therefore, to trap it, you must stop it flowing down - thereby adding weight at high altitudes, like Anon said, which would increase linear velocity. However, the effect would be minute. I must admit I am a bit skeptical of "Understanding Earth" 's (implied) claim that all or most dammable rivers flow toward the equator, and that trapping the water a couple of degrees up (or down) has any measurable effect - enough to cancel out the altitude effect mentioned, anyway. I would like to see some numbers. Referring to books we can buy on Amazon to back up your claims does not cut it. Anyway, the effect must be nearly insignificant. If you're going to start calculating such minute variances, you'd have to take an awful lot of other minor things into account as well - mining springs to mind. Plenty of megatons being shipped around, and unlike dams, the effect is permanent and accumulates. Polar ice. Erosion and earth movements, especially around the equator. A single underground earthquake or volcano in the tropics could easily have more effect, angular-velocity-wise, than all the earth's dams combined. Yes, but water flows towards the centre of gravity first, any other direction second. Therefore, to trap it, you must stop it flowing down – thereby adding weight at high altitudes, like Anon said, which would increase linear velocity. However, the effect would be minute.

I must admit I am a bit skeptical of “Understanding Earth” ’s (implied) claim that all or most dammable rivers flow toward the equator, and that trapping the water a couple of degrees up (or down) has any measurable effect – enough to cancel out the altitude effect mentioned, anyway. I would like to see some numbers. Referring to books we can buy on Amazon to back up your claims does not cut it.

Anyway, the effect must be nearly insignificant. If you’re going to start calculating such minute variances, you’d have to take an awful lot of other minor things into account as well – mining springs to mind. Plenty of megatons being shipped around, and unlike dams, the effect is permanent and accumulates. Polar ice. Erosion and earth movements, especially around the equator. A single underground earthquake or volcano in the tropics could easily have more effect, angular-velocity-wise, than all the earth’s dams combined.

]]> By: philg http://blogs.law.harvard.edu/philg/2008/11/30/weve-trashed-the-land-in-our-search-for-electricity-lets-trash-the-oceans-next/comment-page-1/#comment-94548 philg Tue, 02 Dec 2008 03:34:40 +0000 http://blogs.law.harvard.edu/philg/?p=1143#comment-94548 Anon: I assume you mean "high latitudes". The dams pull water away from the the equator, where it was spinning with a high linear velocity, to a high latitude where it will spin with a much lower linear velocity. To conserve angular momentum the Earth is forced to spin a little bit faster when the mass of water is pulled inwards (Quebec and its hydro dams are closer to the center of the Earth than Quito). Anon: I assume you mean “high latitudes”. The dams pull water away from the the equator, where it was spinning with a high linear velocity, to a high latitude where it will spin with a much lower linear velocity. To conserve angular momentum the Earth is forced to spin a little bit faster when the mass of water is pulled inwards (Quebec and its hydro dams are closer to the center of the Earth than Quito).

]]> By: Anonymous http://blogs.law.harvard.edu/philg/2008/11/30/weve-trashed-the-land-in-our-search-for-electricity-lets-trash-the-oceans-next/comment-page-1/#comment-94547 Anonymous Tue, 02 Dec 2008 02:56:31 +0000 http://blogs.law.harvard.edu/philg/?p=1143#comment-94547 Adding weight at high altitude should slow the rotational speed of the earth, right? Adding weight at high altitude should slow the rotational speed of the earth, right?

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