title: Obliquity-paced climate change recorded in Antarctic debris-covered glaciers.
abstract: The degree to which debris-covered glaciers record past environmental conditions is debated. Here we describe a novel palaeoclimate archive derived from the surface morphology and internal debris within cold-based debris-covered glaciers in Antarctica. Results show that subtle changes in mass balance impart major changes in the concentration of englacial debris and corresponding surface topography, and that over the past ∼220 ka, at least, the changes are related to obliquity-paced solar radiation, manifest as variations in total summer energy. Our findings emphasize solar radiation as a significant driver of mass balance changes in high-latitude mountain systems, and demonstrate that debris-covered glaciers are among the most sensitive recorders of obliquity-paced climate variability in interior Antarctica, in contrast to most other Antarctic archives that favour eccentricity-paced forcing over the same time period. Furthermore, our results open the possibility that similar-appearing debris-covered glaciers on Mars may likewise hold clues to environmental change.
authors.affiliation: Department of Earth and Environment, Boston University, Boston, Massachusetts 02215, USA.
authors.forename: Sean L
authors.initials: SL
authors.lastname: Mackay
authors.affiliation: Department of Earth and Environment, Boston University, Boston, Massachusetts 02215, USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Marchant