~20-cm section of sediment core from Chapel Pond, showing 10-cm layer of
sand and woody forest debris (twigs, bark, leaves, etc)
Click image for high resolution version. Photo by Anders Noren.
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Millennial-scale Storminess Variability in the Northeastern
United States during the Holocene Epoch
Nature,
419, 821 - 824 (2002); doi:10.1038/nature01132
Anders J. Noren1, Paul R. Bierman1,
Eric J. Steig2, Andrea Lini 1,
and John Southon3.
1
Department of Geology, University of Vermont, Burlington, Vermont 05405, USA
2
Quaternary Research Center and Department of Earth and Space Sciences,
University of Washington, Seattle, Washington 98195, USA
3
Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory,
Livermore, California 94551, USA. Present address: Earth System Science,
University of California, Irvine, California 92697-3100, USA
For the purpose of detecting the effects of human activities on climate change, it is important to
document natural change in past climate. In this context, it has proved particularly difficult
to study the variability in the occurrence of extreme climate events, such as storms with
exceptional rainfall. Previous investigations have established storm chronologies using sediment
cores from single lakes, but such studies can be susceptible to local environmental bias.
Here we date terrigenous inwash layers in cores from 13 lakes, which show that the frequency of
storm-related floods in the northeastern United States has varied in regular cycles during the
past 13,000 years (13 kyr), with a characteristic period of about 3 kyr. Our data show four peaks
in storminess during the past 14 kyr, approximately 2.6, 5.8, 9.1 and 11.9 kyr ago. This pattern
is consistent with long-term changes in the average sign of the Arctic Oscillation,
suggesting that modulation of this dominant atmospheric mode may account for a significant
fraction of Holocene climate variability in North America and Europe.
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