Timing of abrupt climate change: A precise clock
Article first published online: 21 MAY 2003
Copyright 2003 by the American Geophysical Union.
Geophysical Research Letters
Volume 30, Issue 10, May 2003
How to Cite
2003), Timing of abrupt climate change: A precise clock, Geophys. Res. Lett., 30, 1510, doi:10.1029/2003GL017115, 10.(
- Issue published online: 21 MAY 2003
- Article first published online: 21 MAY 2003
- Manuscript Accepted: 10 APR 2003
- Manuscript Revised: 27 MAR 2003
- Manuscript Received: 12 FEB 2003
 Many paleoclimatic data reveal a ∼1,500 year cyclicity of unknown origin. A crucial question is how stable and regular this cycle is. An analysis of the GISP2 ice core record from Greenland reveals that abrupt climate events appear to be paced by a 1,470-year cycle with a period that is probably stable to within a few percent; with 95% confidence the period is maintained to better than 12% over at least 23 cycles. This highly precise clock points to an origin outside the Earth system; oscillatory modes within the Earth system can be expected to be far more irregular in period.