Augusto Mangini, Heidelberg Academy of Sciences, by TIMS according to the following protocol. The

• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Augusto; Greenland; Hulu; Greenland ice core; GRIP; ice core
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.210.9550; http://www.geo.umass.edu/climate/papers/burnsetalscience2003correction.pdf

The chronology for the climate time series presented in Burns et al. (1) has been found to be ~2.3 ky too old, due primarily to a systematic standardization error in measurement of the thorium isotopes. A new age model for stalagmite M1-2 based on 19 new Th/U analyses measured by thermal ionization mass spectrometry (TIMS) at the Heidelberg Academy of Sciences and 6 new measurements by induction-coupled plasma mass spectrometry at the University of Bern is shown in Figure S1. A simple linear fit through the data was used to re-calculate ages for individual data points in the stable oxygen isotope time series in Burns et al (1). The slope of this line (7.59 y/mm) is nearly identical to the slope of a linear fit through the original age model (7.60 y/mm). Thus, the pattern of climate change observed in the oxygen isotopes does not change with the new age model. The climate record, however, is moved forward in time by 2,290 y. On the revised time scale the ages of climate events in the record, specifically the Dansgaard/Oeschger cycles, match well with two other independently-dated records (Fig. S2): Hulu Cave stalagmites (2) and the most recent chronology for the GRIP Greenland ice core (3).