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Title: Absence of ice-bonded permafrost beneath an Arctic lagoon revealed by electrical geophysics
Relict permafrost is ubiquitous throughout the Arctic coastal shelf, but little is known about it near shore. The presence and thawing of subsea permafrost are vital information because permafrost stores an atmosphere’s worth of carbon and protects against coastal erosion. Through electrical resistivity imaging across a lagoon on the Alaska Beaufort Sea coast in summer, we found that the subsurface is not ice-bonded down to ~20 m continually from within the lagoon, across the beach, and underneath an ice-wedge polygon on the tundra. This contrasts with the broadly held idea of a gently sloping ice-bonded permafrost table extending from land to offshore. The extensive unfrozen zone is a marine talik connected to on-land cryopeg. This zone is a potential source and conduit for water and dissolved organic matter, is vulnerable to physical degradation, and is liable to changes in biogeochemical processes that affect carbon cycling and climate feedbacks.  more » « less
Award ID(s):
1656026
PAR ID:
10279484
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
6
Issue:
43
ISSN:
2375-2548
Page Range / eLocation ID:
eabb5083
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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