Resolving the Younger Dryas Event Through Borehole Thermometry

Meltwater influxes may partly explain the low oxygen-isotope values measured in the Dye 3 and Camp Century ice cores. This has led to speculation that Greenland may not have cooled during the Younger Dryas and underlined the need for independent checks of the oxygen-isotope record. Using optimal control methods and heat-flow modeling, the author makes a valiant but ultimately futile attempt to distinguish the Younger Dryas event in the ice-sheet temperatures measured at Dye 3, south Greenland. The author discusses the prospects for attempting the same in the new Summit boreholes in central Greenland: how that will require more accurate temperature measurements, a coupled thermo-mechanical model and a refined uncertainty analysis. He concludes by discussing how borehole-temperature analysis may improve the climate histories determined from ice cores