Letter

Nature 452, 616-619 (3 April 2008) | doi:10.1038/nature06763; Received 14 May 2007; Accepted 21 January 2008

Dust-climate couplings over the past 800,000 years from the EPICA Dome C ice core

F. Lambert1,2, B. Delmonte3, J. R. Petit4, M. Bigler1,5, P. R. Kaufmann1,2, M. A. Hutterli6, T. F. Stocker1,2, U. Ruth7, J. P. Steffensen5 & V. Maggi3

  1. Climate and Environmental Physics, Physics Institute, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland
  2. Oeschger Centre for Climate Change Research, University of Bern, 3012 Bern, Switzerland
  3. Environmental Sciences Department, University of Milano Bicocca, Piazza della Scienza 1, 20126 Milano, Italy
  4. Laboratoire de Glaciologie et Géophysique de l'Environment (LGGE), CNRS-University J. Fourier, BP96 38402 Saint-Martin-d'Hères cedex, France
  5. Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen OE, Denmark
  6. British Antarctic Survey, High Cross, Madingley Road, Cambridge CB3 0ET, UK
  7. Alfred Wegener Institute for Polar and Marine Research, Columbusstrasse, 27568 Bremerhaven, Germany

Correspondence to: J. R. Petit4 Correspondence and requests for materials should be addressed to J.R.P. (Email: petit@lgge.obs.ujf-grenoble.fr).

Dust can affect the radiative balance of the atmosphere by absorbing or reflecting incoming solar radiation1; it can also be a source of micronutrients, such as iron, to the ocean2. It has been suggested that production, transport and deposition of dust is influenced by climatic changes on glacial-interglacial timescales3, 4, 5, 6. Here we present a high-resolution record of aeolian dust from the EPICA Dome C ice core in East Antarctica, which provides an undisturbed climate sequence over the past eight climatic cycles7, 8. We find that there is a significant correlation between dust flux and temperature records during glacial periods that is absent during interglacial periods. Our data suggest that dust flux is increasingly correlated with Antarctic temperature as the climate becomes colder. We interpret this as progressive coupling of the climates of Antarctic and lower latitudes. Limited changes in glacial-interglacial atmospheric transport time4, 9, 10 suggest that the sources and lifetime of dust are the main factors controlling the high glacial dust input. We propose that the observed approx25-fold increase in glacial dust flux over all eight glacial periods can be attributed to a strengthening of South American dust sources, together with a longer lifetime for atmospheric dust particles in the upper troposphere resulting from a reduced hydrological cycle during the ice ages.