Cosmic Dust in Ice Cores Sheds Light on Earth's Past Climate
Each year, nearly 40,000 tons of cosmic dust fall to Earth from outer space. Now, the first successful chronological study of extraterrestrial dust in an Antarctic ice core has shown that this amount has remained largely constant over the past 30,000 years, a finding that could help refine efforts to understand the timing and effects of changes in the Earth's past climate.
The study, which appears a recent issue of the journal Science, involved researchers from the Lamont-Doherty Earth Observatory, a part of The Earth Institute at Columbia University, and the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, Germany. The depth of the core they examined corresponded to the period between 6,800 years and 29,000 years before the present day - a span that includes the height of the last glacial period, and the transition to warm conditions similar to today.