Reconstruction of temperature, accumulation rate, and layer thinning from an ice core at South Pole using a statistical inverse method | CU Experts

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 sensitivity of water isotopes to temperature is; greater than previously assumed for East Antarctica. The temperature; reconstruction yields a glacial-interglacial temperature change of; 6.3±0.8°C at the South Pole.

Kahle EC; Steig EJ; Jones TR; Fudge TJ; Koutnik MR; Morris V; Vaughn B; Schauer A; Stevens CM; Conway H

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