2011-04-25 11:13:12A 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.