DOI: 10.5194/tc-15-1907-2021
论文题名: Mapping potential signs of gas emissions in ice of Lake Neyto, Yamal, Russia, using synthetic aperture radar and multispectral remote sensing data
作者: Pointner G. ; Bartsch A. ; A. Dvornikov Y. ; Kouraev A.V.
刊名: Cryosphere
ISSN: 19940416
出版年: 2021
卷: 15, 期: 4 起始页码: 1907
结束页码: 1929
语种: 英语
英文关键词: backscatter
; borehole
; flooding
; in situ measurement
; lacustrine deposit
; mapping method
; pixel
; satellite data
; satellite imagery
; synthetic aperture radar
; Arctic
; Russian Federation
; Siberia
英文摘要: Regions of anomalously low backscatter in C-band synthetic aperture radar (SAR) imagery of lake ice of Lake Neyto in northwestern Siberia have been suggested to be caused by emissions of gas (methane from hydrocarbon reservoirs) through the lake's sediments. However, to assess this connection, only analyses of data from boreholes in the vicinity of Lake Neyto and visual comparisons to medium-resolution optical imagery have been provided due to a lack of in situ observations of the lake ice itself. These observations are impeded due to accessibility and safety issues. Geospatial analyses and innovative combinations of satellite data sources are therefore proposed to advance our understanding of this phenomenon. In this study, we assess the nature of the backscatter anomalies in Sentinel-1 C-band SAR images in combination with very high resolution (VHR) WorldView-2 optical imagery. We present methods to automatically map backscatter anomaly regions from the C-band SAR data (40 m pixel spacing) and holes in lake ice from the VHR data (0.5 m pixel spacing) and examine their spatial relationships. The reliability of the SAR method is evaluated through comparison between different acquisition modes. The results show that the majority of mapped holes (71 %) in the VHR data are clearly related to anomalies in SAR imagery acquired a few days earlier, and similarities to SAR imagery acquired more than a month before are evident, supporting the hypothesis that anomalies may be related to gas emissions. Further, a significant expansion of backscatter anomaly regions in spring is documented and quantified in all analysed years 2015 to 2019. Our study suggests that the backscatter anomalies might be caused by lake ice subsidence and consequent flooding through the holes over the ice top leading to wetting and/or slushing of the snow around the holes, which might also explain outcomes of polarimetric analyses of auxiliary L-band Advanced Land Observing Satellite (ALOS) Phased Array type L-band Synthetic Aperture Radar-2 (PALSAR-2) data. C-band SAR data are considered to be valuable for the identification of lakes showing similar phenomena across larger areas in the Arctic in future studies. © 2021 EDP Sciences. All rights reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/164783
Appears in Collections: 气候变化与战略
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作者单位: B.geos, Korneuburg, Austria; Austrian Polar Research Institute, Vienna, Austria; Department of Geoinformatics - Z_GIS, DK GIScience, Paris Lodron University of Salzburg, Salzburg, Austria; Department of Landscape Design and Sustainable Ecosystems, Agrarian-Technological Institute, Peoples' Friendship University of Russia, Moscow, Russian Federation; LEGOS, Université de Toulouse, CNES, CNRS, IRD, UPS, Toulouse, France; Department of Geology and Geography, Tomsk State University, Tomsk, Russian Federation
Recommended Citation:
Pointner G.,Bartsch A.,A. Dvornikov Y.,et al. Mapping potential signs of gas emissions in ice of Lake Neyto, Yamal, Russia, using synthetic aperture radar and multispectral remote sensing data[J]. Cryosphere,2021-01-01,15(4)