30,000 years of cosmic dust in Antarctic ice.

نویسندگان

  • Gisela Winckler
  • Hubertus Fischer
چکیده

Polar ice provides an archive for the influx of cosmic dust. Here, we present a high-resolution, glacial-to-interglacial record of cosmic dust using helium isotope analysis of the European Project for Ice Coring in Antarctica (EPICA) ice core drilled in Dronning Maud Land. We obtained a relatively constant 3He flux over the past 30,000 years. This finding excludes 3He as a pacemaker of late Pleistocene glacial cycles. Rather, it supports 3He as a constant flux parameter in paleoclimatic studies. A last glacial-to-Holocene shift of the 4He/non-sea salt Ca2+ ratio appears to indicate a glacial-to-interglacial change in the terrestrial dust source.

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عنوان ژورنال:
  • Science

دوره 313 5786  شماره 

صفحات  -

تاریخ انتشار 2006