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.

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.