Surface displacement revealed by L-band InSAR analysis in the Mayya area, Central Yakutia, underlain by continuous permafrost

Earth, Planets and Space

Takahiro Abe¹  Takeo Tadono¹  Kazuki Yanagiya²  Go Iwahana³  Takumi Kawamura⁴  Petr V. Efremov⁵  Alexey R. Desyatkin⁶  Alexander Fedorov⁷  Yuri Zhegusov⁸ 

[1] Earth Observation Research Center, Japan Aerospace Exploration Agency, 305-8505, Tsukuba, Japan;Graduate School of Science, Hokkaido University, 060-0810, Sapporo, Japan;International Arctic Research Center, University of Alaska Fairbanks, 99775, Fairbanks, AK, USA;Arctic Research Center, Hokkaido University, 001-0021, Sapporo, Japan;Iwata Chizaki Inc., 060-8630, Sapporo, Japan;Melnikov Permafrost Institute, 36 Merzlotnaya Str, 677010, Yakutsk, Russia;Melnikov Permafrost Institute, 36 Merzlotnaya Str, 677010, Yakutsk, Russia;Institute for Biological Problems of Cryolithozone, 41 Lenina Ave, 677980, Yakutsk, Russia;Melnikov Permafrost Institute, 36 Merzlotnaya Str, 677010, Yakutsk, Russia;North-Eastern Federal University, 58 Belinsky Str. 677007, Yakutsk, Russia;North-Eastern Federal University, 58 Belinsky Str. 677007, Yakutsk, Russia;

关键词: Permafrost;    Thermokarst;    Central Yakutia;    Siberia;    InSAR;    Stacking;    L-band;    ALOS;    ALOS-2;   

DOI  :  10.1186/s40623-020-01266-3

来源: Springer

【 摘 要 】

Recent increases in global temperature have stimulated permafrost degradation associated with landform deformation caused by the melting of excess ground ice (thermokarst). Central Yakutia is underlain by ice-rich continuous permafrost, and there are complicated permafrost-related features in forested and deforested areas. This situation makes thermokarst monitoring necessary over a wide area to achieve a better understanding of its dynamics. As a case study, we applied L-band InSAR analysis to map surface subsidence due to thermokarst in this area and to demonstrate the suitability of L-band SAR for such monitoring. Our results show that InSAR detected subsidence/uplift signals in deforested areas and alasses; whereas, there were few ground deformation signals in forested areas with middle coherence. The InSAR stacking process, including both seasonal and inter-annual displacements, showed subsidence in deforested areas during 2007–2010 and 2015–2018, in the range of 0.5–3 cm yr−1. We also estimated the inter-annual subsidence to be up to 2 cm yr−1 during 2015–2018, using InSAR pairs that spanned the same seasonal interval but in different years. The magnitude of subsidence and the spatial patterns are qualitatively reasonable as thermokarst subsidence compared to observations using field surveys and high-resolution optical images. L-band InSAR was effective in maintaining coherence over a long period for a partially forested thermokarst-affected area, which resulted in deriving the inter-annual subsidence by the stacking using four interferograms. The advantage of the persistent coherence in L-band InSAR is crucial to better understand thermokarst processes in permafrost regions.

【 授权许可】

CC BY