NOAA NCDC National Climatic Data Center
NOAA Paleoclimatology Program, NCDC Paleoclimatology Branch  
Paleoclimatology Navigation Bar Bookmark and Share
NOAA National Environmental Satellite, Data, and Information Service National Oceanic and Atmospheric Administration NOAA National Climatic Data Center U.S. Department of Commerce Paleo Home Data Paleo Projects Paleo Perspectives Education and Outreach About Paleo Program Site Map
WDC Paleo logo

Ice Core Gateway

WDC Glaciology logo
Access Data: Listed by Project Listed by Data Type Search (Free Text) Search by Variable, PI, More

Vostok Ice Core Timescales

Different timescales have been used for the interpretation of Vostok ice core records. They are reported in ky BP.

- The Ruddiman and Raymo (2003) Methane-Based Time Scale was developed by tuning the Vostok methane signal to mid-July 30°N insolation.

- The Petit et al. GT4 timescale extends the glaciological timescale of Jouzel et al.

- The Lorius et al. timescale (column 2) has been derived by combining a glaciological model, fully described in Ritz (1992) and an accumulation model in which past accumulation is derived from the temperature record reconstructed from the deuterium isotopic profile (see Lorius et al., 1985).

- Sowers et al. correlated the d18O of paleoatmospheric O2 derived from the Vostok 3G and 4G cores, into a record of changes in the d18O of sea water derived from records of the d18O of foraminifera (see Sowers et al., 1993). This timescale is given in column 3.

- The glaciological timescale of Lorius et al. (1985) has been extended accounting for a linear increase of modern accumulation upstream of Vostok. This Extended Glaciological Timescale (EGT; column 4) is described in Jouzel et al. (1993).

- Jouzel et al. (1996) have used a modified version of EGT (column 4) assuming that this timescale overestimates the increase of age with depth by 12% for gas ages older than 112 ky BP.

Dividing Line
Privacy Policy information Open Access Climate Data Policy link USA logo Disclaimer information
Dividing Line
Downloaded Friday, 27-Feb-2015 19:59:25 EST
Last Updated Wednesday, 26-Dec-2012 08:18:56 EST by
Please see the Paleoclimatology Contact Page or the NCDC Contact Page if you have questions or comments.