TY - JOUR

T1 - Serpentine (Floating) Ice Channels and their Interaction with Riverbed Permafrost in the Lena River Delta, Russia

AU - Juhls, Bennet

AU - Antonova, Sofia

AU - Angelopoulos, Michael

AU - Bobrov, Nikita

AU - Grigoriev, Mikhail

AU - Langer, Moritz

AU - Maksimov, Georgii

AU - Miesner, Frederieke

AU - Overduin, Pier Paul

N1 - Publisher Copyright: © Copyright © 2021 Juhls, Antonova, Angelopoulos, Bobrov, Grigoriev, Langer, Maksimov, Miesner and Overduin.

PY - 2021/7/6

Y1 - 2021/7/6

N2 - Arctic deltas and their river channels are characterized by three components of the cryosphere: snow, river ice, and permafrost, making them especially sensitive to ongoing climate change. Thinning river ice and rising river water temperatures may affect the thermal state of permafrost beneath the riverbed, with consequences for delta hydrology, erosion, and sediment transport. In this study, we use optical and radar remote sensing to map ice frozen to the riverbed (bedfast ice) vs. ice, resting on top of the unfrozen water layer (floating or so-called serpentine ice) within the Arctic’s largest delta, the Lena River Delta. The optical data is used to differentiate elevated floating ice from bedfast ice, which is flooded ice during the spring melt, while radar data is used to differentiate floating from bedfast ice during the winter months. We use numerical modeling and geophysical field surveys to investigate the temperature field and sediment properties beneath the riverbed. Our results show that the serpentine ice identified with both types of remote sensing spatially coincides with the location of thawed riverbed sediment observed with in situ geoelectrical measurements and as simulated with the thermal model. Besides insight into sub-river thermal properties, our study shows the potential of remote sensing for identifying river channels with active sub-ice flow during winter vs. channels, presumably disconnected for winter water flow. Furthermore, our results provide viable information for the summer navigation for shallow-draught vessels.

AB - Arctic deltas and their river channels are characterized by three components of the cryosphere: snow, river ice, and permafrost, making them especially sensitive to ongoing climate change. Thinning river ice and rising river water temperatures may affect the thermal state of permafrost beneath the riverbed, with consequences for delta hydrology, erosion, and sediment transport. In this study, we use optical and radar remote sensing to map ice frozen to the riverbed (bedfast ice) vs. ice, resting on top of the unfrozen water layer (floating or so-called serpentine ice) within the Arctic’s largest delta, the Lena River Delta. The optical data is used to differentiate elevated floating ice from bedfast ice, which is flooded ice during the spring melt, while radar data is used to differentiate floating from bedfast ice during the winter months. We use numerical modeling and geophysical field surveys to investigate the temperature field and sediment properties beneath the riverbed. Our results show that the serpentine ice identified with both types of remote sensing spatially coincides with the location of thawed riverbed sediment observed with in situ geoelectrical measurements and as simulated with the thermal model. Besides insight into sub-river thermal properties, our study shows the potential of remote sensing for identifying river channels with active sub-ice flow during winter vs. channels, presumably disconnected for winter water flow. Furthermore, our results provide viable information for the summer navigation for shallow-draught vessels.

KW - cryosphere

KW - geophysics

KW - hydrology

KW - lena river delta

KW - navigation

KW - permafrost

KW - remote sensing

KW - river ice

UR - http://www.scopus.com/inward/record.url?scp=85111070664&partnerID=8YFLogxK

U2 - 10.3389/feart.2021.689941

DO - 10.3389/feart.2021.689941

M3 - Article

AN - SCOPUS:85111070664

VL - 9

JO - Frontiers of Earth Science

JF - Frontiers of Earth Science

SN - 1673-7385

M1 - 689941

ER -