The heterogeneous distribution of ground ice in the Arctic is a key driver of uneven ground subsidence as permafrost thaws, significantly impacting infrastructure and surface/subsurface hydrology. These topographic and hydrological changes contribute to major uncertainties in energy and carbon fluxes and storage in a warming Arctic. This study aims to improve our understanding of the controls on ground ice and organic matter distribution within the top 3 m of permafrost in coastal polygonal tundra near Utqiagvik, Alaska. To this end, we apply a neural network approach to bulk density distributions derived from nondestructive X-ray tomography of soil cores, trained with laboratory analyses, to improve the resolution and spatial coverage of estimates of dry bulk density, ice content, and organic matter content. In addition, we use capacitively coupled geophysical imaging to map soil electrical conductivity and salinity variations. The results show that sedimentary deposits from ocean transgressions, along with subsequent ice wedge polygon geomorphological processes, jointly influence the distribution of ice content at various scales. The impact of the latter decreases with depth, whereas the influence of salinity and sedimentary history increases. Although the controls on the distribution of soil organic matter content (g/cm3) remain unclear, the pronounced heterogeneity in bulk density strongly influences its calculation from laboratory mass fraction measurements (g/g). From a methodological perspective, the interdependencies among soil components and the need for increased data coverage underscore the value of high-resolution density measurements, such as using X-ray tomography. Overall, this study emphasizes the importance of considering salinity constraints on ice content distribution in coastal permafrost regions. The results are expected to aid in the development of data products and process representations in geomorphological and ecosystem models.
Dafflon, Baptiste, et al. "Impact of Salinity on Ground Ice Distribution Across an Arctic Coastal Polygonal Tundra Environment." Permafrost and Periglacial Processes, vol. 36, no. 4, Sep. 2025. https://doi.org/10.1002/ppp.70008
Dafflon, Baptiste, Soom, Florian, Ulrich, Craig, et al., "Impact of Salinity on Ground Ice Distribution Across an Arctic Coastal Polygonal Tundra Environment," Permafrost and Periglacial Processes 36, no. 4 (2025), https://doi.org/10.1002/ppp.70008
@article{osti_3002569,
author = {Dafflon, Baptiste and Soom, Florian and Ulrich, Craig and Wainwright, Haruko and Kneafsey, Timothy and Lopez, Robin and Peterson, John and Wu, Yuxin and Hubbard, Susan},
title = {Impact of Salinity on Ground Ice Distribution Across an Arctic Coastal Polygonal Tundra Environment},
annote = {The heterogeneous distribution of ground ice in the Arctic is a key driver of uneven ground subsidence as permafrost thaws, significantly impacting infrastructure and surface/subsurface hydrology. These topographic and hydrological changes contribute to major uncertainties in energy and carbon fluxes and storage in a warming Arctic. This study aims to improve our understanding of the controls on ground ice and organic matter distribution within the top 3 m of permafrost in coastal polygonal tundra near Utqiagvik, Alaska. To this end, we apply a neural network approach to bulk density distributions derived from nondestructive X-ray tomography of soil cores, trained with laboratory analyses, to improve the resolution and spatial coverage of estimates of dry bulk density, ice content, and organic matter content. In addition, we use capacitively coupled geophysical imaging to map soil electrical conductivity and salinity variations. The results show that sedimentary deposits from ocean transgressions, along with subsequent ice wedge polygon geomorphological processes, jointly influence the distribution of ice content at various scales. The impact of the latter decreases with depth, whereas the influence of salinity and sedimentary history increases. Although the controls on the distribution of soil organic matter content (g/cm3) remain unclear, the pronounced heterogeneity in bulk density strongly influences its calculation from laboratory mass fraction measurements (g/g). From a methodological perspective, the interdependencies among soil components and the need for increased data coverage underscore the value of high-resolution density measurements, such as using X-ray tomography. Overall, this study emphasizes the importance of considering salinity constraints on ice content distribution in coastal permafrost regions. The results are expected to aid in the development of data products and process representations in geomorphological and ecosystem models.},
doi = {10.1002/ppp.70008},
url = {https://www.osti.gov/biblio/3002569},
journal = {Permafrost and Periglacial Processes},
issn = {ISSN 1045-6740},
number = {4},
volume = {36},
place = {United States},
publisher = {Wiley - International Permafrost Association},
year = {2025},
month = {09}}
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
US Department of Energy; USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23), Climate and Environmental Sciences Division (SC-23.1 ); USDOE Office of Science (SC), Biological and Environmental Research (BER). Earth & Environmental Systems Science (EESS)
Grant/Contract Number:
AC02-05CH11231; AC05-00OR22725
OSTI ID:
3002569
Alternate ID(s):
OSTI ID: 2997927
Journal Information:
Permafrost and Periglacial Processes, Journal Name: Permafrost and Periglacial Processes Journal Issue: 4 Vol. 36; ISSN 1099-1530; ISSN 1045-6740