Arctic coastal barriers: a long-term record of rapid environmental changes
OCCI Funded Project: 2007
Abstract
Low-lying Arctic coasts have experienced numerous
episodes of erosion and retreat in their geologic history. Recent rise in temperature, reduction in
sea-ice cover, and melting of coastal permafrost are predicted to make coastal
regions more vulnerable to erosion in the future. Along sandy coasts, extreme events often
leave diagnostic morphological and sedimentological signatures in ancient beach
and dune deposits. The combination of
high-resolution subsurface imaging with optical dating of individual event
horizons can be used to reconstruct regional histories of extreme events in the
Arctic. The proposed
investigation focuses on coastal sites in Kotzebue Sound, Alaska where both Pacific and Arctic storms are recognized
as important agents of coastal change.This research will extend the instrumental records of large-magnitude
erosional episodes, while refining the existing chronology of storminess and
climatic change as far back as 5,000 years.Integrating field research with theoretical numerical modeling, the
proposed project will not only shed light on the local record of climactic
change, but will aid in developing our understanding of how beach ridge
orientation responds to changes in wave climate. This research is part of a larger initiative
aimed at reconstructing the return periods of major climatic and oceanographic
events and to assessing their future impact on Arctic coasts.