气候变化领域集成服务门户(CCPortal): New ground ice maps for Canada using a paleogeographic modelling approach

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DOI	10.5194/tc-13-753-2019
	New ground ice maps for Canada using a paleogeographic modelling approach
	O'Neill H.B.; Wolfe S.A.; Duchesne C.
发表日期	2019
ISSN	19940416
EISSN	13
起始页码	753
结束页码	773
卷号	13 期号:3
英文摘要	Ground ice melt caused by climate-induced permafrost degradation may trigger significant ecological change, damage infrastructure, and alter biogeochemical cycles. The fundamental ground ice mapping for Canada is now >20 years old and does not include significant new insights gained from recent field- and remote-sensing-based studies. New modelling incorporating paleogeography is presented in this paper to depict the distribution of three ground ice types (relict ice, segregated ice, and wedge ice) in northern Canada. The modelling uses an expert-system approach in a geographic information system (GIS), founded in conceptual principles gained from empirically based research, to predict ground ice abundance in near-surface permafrost. Datasets of surficial geology, deglaciation, paleovegetation, glacial lake and marine limits, and modern permafrost distribution allow representations in the models of paleoclimatic shifts, tree line migration, marine and glacial lake inundation, and terrestrial emergence, and their effect on ground ice abundance. The model outputs are generally consistent with field observations, indicating abundant relict ice in the western Arctic, where it has remained preserved since deglaciation in thick glacigenic sediments in continuous permafrost. Segregated ice is widely distributed in fine-grained deposits, occurring in the highest abundance in glacial lake and marine sediments. The modelled abundance of wedge ice largely reflects the exposure time of terrain to low air temperatures in tundra environments following deglaciation or marine/glacial lake inundation and is thus highest in the western Arctic. Holocene environmental changes result in reduced ice abundance where the tree line advanced during warmer periods. Published observations of thaw slumps and massive ice exposures, segregated ice and associated landforms, and ice wedges allow a favourable preliminary assessment of the models, and the results are generally comparable with the previous ground ice mapping for Canada. However, the model outputs are more spatially explicit and better reflect observed ground ice conditions in many regions. Synthetic modelling products that incorporated the previous ground ice information may therefore include inaccuracies. The presented modelling approach is a significant advance in permafrost mapping, but additional field observations and volumetric ice estimates from more areas in Canada are required to improve calibration and validation of small-scale ground ice modelling. The ground ice maps from this paper are available in the supplement in GeoTIFF format. © 2019 Author(s).
学科领域	calibration; deglaciation; degradation; environmental change; expert system; fine grained sediment; GIS; glacial environment; glacial lake; Holocene; hydrological modeling; ice mechanics; infrastructure; marine sediment; melt; paleogeography; permafrost; remote sensing; Arctic; Canada
语种	英语
scopus关键词	calibration; deglaciation; degradation; environmental change; expert system; fine grained sediment; GIS; glacial environment; glacial lake; Holocene; hydrological modeling; ice mechanics; infrastructure; marine sediment; melt; paleogeography; permafrost; remote sensing; Arctic; Canada
来源期刊	The Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/118916
作者单位	Geological Survey of Canada, Natural Resources Canada, 601 Booth St., Ottawa, ON, Canada
推荐引用方式 GB/T 7714	O'Neill H.B.,Wolfe S.A.,Duchesne C.. New ground ice maps for Canada using a paleogeographic modelling approach[J],2019,13(3).
APA	O'Neill H.B.,Wolfe S.A.,&Duchesne C..(2019).New ground ice maps for Canada using a paleogeographic modelling approach.The Cryosphere,13(3).
MLA	O'Neill H.B.,et al."New ground ice maps for Canada using a paleogeographic modelling approach".The Cryosphere 13.3(2019).