Monte Carlo inverse modelling of the Law Dome (Antarctica) temperature profile

Annals of Glaciology, Vol. 29, p. 145-150, 1999

D. Dahl-Jensen
Departement of Geophysics, The Niels Bohr Institute of Astronomy, Physics and Geophysics, University of Copenhagen.
V.I. Morgan, A. Elcheikh
Antarctic CRC and Australian Antarctic Division, Box 252-80, Hobart, Tasmania 7001, Australia.

ABSTRACT.
The temperature profile in the 1200 m deep Dome Summit South (DSS) borehole near the summit of Law Dome, Antarctica was measured in 1996, 3 years after the termination of the deep drilling. The temperature profile contains information on past surface temperature over the last 4 ka. This temperature history is determined by the use of a Monte Carlo inverse method in which no constraints are placed on the unknown temperature history and no solution is assumed to be unique. The temperature history is obtained from a selection of equally well-fitting solutions by a statistical treatment. The results show solutions covering the last 4 ka have a well-developed central value, a most likely temperature history. The temperature record has two well-developed minima at AD 1250 and 1850. From 1850 to the present, temperatures have gradually increased by 0.7 K. The reconstructed temperatures are compared with the stable oxygen isotope δ¹⁸O) from the DSS ice core.