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2011-04-25 11:13:12 | A silly question re: Vostok ice core | |
citizenschallenge Peter Miesler citizenschallenge7@gmail... 166.128.31.160 |
Can anyone tell me what the upper end of the Vostok 420,000 year old ice core is? Such as; zero on their time scale equals year?
I'm not finding that in any of the write ups I been looking through - don't even ask why it matters ;-) | |
2011-04-25 11:21:35 | ||
Daniel Bailey Daniel Bailey yooper49855@hotmail... 97.83.150.37 |
Should be 1950 (such says my memory, which occasionally lieth like a dog). Revisiting Petit et al 1999 shows a mean resolution of ± 1,500 years for CO2; the deeper one goes, the poorer the resolution gets (± 15,000 years for the deepest ice).
Some industrious chap* should do a post on ice core dating and modern baseline dates.
* Someone other than me. | |
2011-04-25 12:17:40 | ||
Alex C coultera@umich... 67.149.101.148 |
Yeah, usually the upper end of most proxy records, if measured "from present," is 1950 since that's a standard for carbon dating (?). I'm not sure though if the actual data extends that close; I don't know how accurate they judge newer ice to be, as per issues with compacting ice, etc. | |
2011-04-26 12:16:57 | ||
citizenschallenge Peter Miesler citizenschallenge7@gmail... 166.183.7.204 |
Thanks for the info. |