Data from the South Pole ice core (SPC14) are used to constrain climate conditions and ice‐flow‐induced layer thinning for the last 54,000 years. Empirical constraints are obtained from the SPC14 ice and gas timescales, used to calculate annual‐layer thickness and the gas‐ice age difference (Δage), and from high‐resolution measurements of water isotopes, used to calculate the water‐isotope diffusion length. Both Δage and diffusion length depend on firn properties and therefore contain information about past temperature and snow‐accumulation rate. A statistical inverse approach is used to obtain an ensemble of reconstructions of temperature, accumulation‐rate, and thinning of annual layers in the ice sheet at the SPC14 site. The traditional water‐isotope/temperature relationship is not used as a constraint; the results therefore provide an independent calibration of that relationship. The temperature reconstruction yields a glacial‐interglacial temperature change of 6.7 ± 1.0°C at the South Pole. The sensitivity of
Reconstructing the history of polar temperature from ice core water isotope (
This paper develops a new framework called the unified slope equations (USE) to provide, for the first time, a general relation among various spatial and temporal water isotope–temperature slopes. The application of the USE to Antarctic deglacial temperature change shows that the optimal paleothermometer is the seasonal slope of the inversion layer temperature.
- NSF-PAR ID:
- 10403984
- Publisher / Repository:
- American Meteorological Society
- Date Published:
- Journal Name:
- Journal of Climate
- Volume:
- 36
- Issue:
- 9
- ISSN:
- 0894-8755
- Page Range / eLocation ID:
- p. 2933-2957
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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