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Re: no leap second coming in December
From: Frank Reed CT
Date: 2004 Jul 29, 14:17 EDT
From: Frank Reed CT
Date: 2004 Jul 29, 14:17 EDT
George H wrote:
"We keep getting told that the polar ice caps in Antarctica and Greenland are melting. However, this displacement of mass, from being locked in the ice caps near the Earth's axis, where it has little effect on the Earth's rotational inertia, to disperse around the oceans where its effect on inertia would be greater, could only slow the Earth's spin, not speed it up."
Well it's true that 'we keep getting told' but it's largely based on circumstantial evidence at this time, so it's worth "entertaining" alternative hypotheses. When this topic (exactly this topic!) came up on another message board a few months ago, I briefly considered the possibility that the Antarctic ice sheet is getting thicker. When you do the numbers, it would require an improbably large amount of ice so we can safely dismiss that possibility. It appears that there is no reservoir of angular momentum above the Earth's mantle that could account for these long-term fluctuations in the Earth's rotation. So the only conclusion that is left to us is that there are massive angular momentum transfers occurring deep within the Earth's interior.
Frank R
[X] Mystic, Connecticut
[ ] Chicago, Illinois
"We keep getting told that the polar ice caps in Antarctica and Greenland are melting. However, this displacement of mass, from being locked in the ice caps near the Earth's axis, where it has little effect on the Earth's rotational inertia, to disperse around the oceans where its effect on inertia would be greater, could only slow the Earth's spin, not speed it up."
Well it's true that 'we keep getting told' but it's largely based on circumstantial evidence at this time, so it's worth "entertaining" alternative hypotheses. When this topic (exactly this topic!) came up on another message board a few months ago, I briefly considered the possibility that the Antarctic ice sheet is getting thicker. When you do the numbers, it would require an improbably large amount of ice so we can safely dismiss that possibility. It appears that there is no reservoir of angular momentum above the Earth's mantle that could account for these long-term fluctuations in the Earth's rotation. So the only conclusion that is left to us is that there are massive angular momentum transfers occurring deep within the Earth's interior.
Frank R
[X] Mystic, Connecticut
[ ] Chicago, Illinois
