{"title":"尼泊尔Khumbu和Lhotse山谷基于insar速度的岩石冰川冰含量模拟","authors":"Yan Hu, S. Harrison, Lin Liu, J. Wood","doi":"10.5194/tc-17-2305-2023","DOIUrl":null,"url":null,"abstract":"Abstract. Active rock glaciers are viscous flow features embodying\nice-rich permafrost and other ice masses. They contain significant amounts\nof ground ice and serve as potential freshwater reservoirs as mountain\nglaciers melt in response to climate warming. However, current knowledge\nabout ice content in rock glaciers has been acquired mainly from in situ\ninvestigations in limited study areas, which hinders a comprehensive\nunderstanding of ice storage in rock glaciers situated in remote mountains\nover local to regional scales. This study proposes a novel approach for\nassessing the hydrological value of rock glaciers in a more quantitative way\nand presents exploratory results focusing on a small region. We develop an\nempirical rheological model to infer ice content of rock glaciers using\nreadily available input data, including rock glacier planar shape, surface\nslope angle, active layer thickness, and surface velocity. The model is\ncalibrated and validated using observational data from the Chilean Andes and\nthe Swiss Alps. We apply the model to five rock glaciers in the Khumbu and\nLhotse valleys, northeastern Nepal. The velocity constraints\napplied to the model are derived from interferometric synthetic aperture\nradar (InSAR) measurements. The volume of rock glacier is estimated based on\nan existing scaling approach. The inferred volumetric ice fraction in the Khumbu\nand Lhotse valleys ranges from 70 ± 8 % to 74 ± 8 %, and the\nwater volume equivalents lie between 1.4 ± 0.2 and 5.9±0.6×106 m3 for the coherently moving parts of individual rock glaciers.\nDue to the accessibility of the model inputs, our approach is applicable to\npermafrost regions where observational data are lacking, which is valuable for\nestimating the water storage potential of rock glaciers in remote areas.\n","PeriodicalId":56315,"journal":{"name":"Cryosphere","volume":null,"pages":null},"PeriodicalIF":4.4000,"publicationDate":"2023-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":"{\"title\":\"Modelling rock glacier ice content based on InSAR-derived velocity, Khumbu and Lhotse valleys, Nepal\",\"authors\":\"Yan Hu, S. Harrison, Lin Liu, J. Wood\",\"doi\":\"10.5194/tc-17-2305-2023\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Abstract. Active rock glaciers are viscous flow features embodying\\nice-rich permafrost and other ice masses. They contain significant amounts\\nof ground ice and serve as potential freshwater reservoirs as mountain\\nglaciers melt in response to climate warming. However, current knowledge\\nabout ice content in rock glaciers has been acquired mainly from in situ\\ninvestigations in limited study areas, which hinders a comprehensive\\nunderstanding of ice storage in rock glaciers situated in remote mountains\\nover local to regional scales. This study proposes a novel approach for\\nassessing the hydrological value of rock glaciers in a more quantitative way\\nand presents exploratory results focusing on a small region. We develop an\\nempirical rheological model to infer ice content of rock glaciers using\\nreadily available input data, including rock glacier planar shape, surface\\nslope angle, active layer thickness, and surface velocity. The model is\\ncalibrated and validated using observational data from the Chilean Andes and\\nthe Swiss Alps. We apply the model to five rock glaciers in the Khumbu and\\nLhotse valleys, northeastern Nepal. The velocity constraints\\napplied to the model are derived from interferometric synthetic aperture\\nradar (InSAR) measurements. The volume of rock glacier is estimated based on\\nan existing scaling approach. The inferred volumetric ice fraction in the Khumbu\\nand Lhotse valleys ranges from 70 ± 8 % to 74 ± 8 %, and the\\nwater volume equivalents lie between 1.4 ± 0.2 and 5.9±0.6×106 m3 for the coherently moving parts of individual rock glaciers.\\nDue to the accessibility of the model inputs, our approach is applicable to\\npermafrost regions where observational data are lacking, which is valuable for\\nestimating the water storage potential of rock glaciers in remote areas.\\n\",\"PeriodicalId\":56315,\"journal\":{\"name\":\"Cryosphere\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":4.4000,\"publicationDate\":\"2023-06-08\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"1\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Cryosphere\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://doi.org/10.5194/tc-17-2305-2023\",\"RegionNum\":2,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"GEOGRAPHY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cryosphere","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.5194/tc-17-2305-2023","RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"GEOGRAPHY, PHYSICAL","Score":null,"Total":0}
Modelling rock glacier ice content based on InSAR-derived velocity, Khumbu and Lhotse valleys, Nepal
Abstract. Active rock glaciers are viscous flow features embodying
ice-rich permafrost and other ice masses. They contain significant amounts
of ground ice and serve as potential freshwater reservoirs as mountain
glaciers melt in response to climate warming. However, current knowledge
about ice content in rock glaciers has been acquired mainly from in situ
investigations in limited study areas, which hinders a comprehensive
understanding of ice storage in rock glaciers situated in remote mountains
over local to regional scales. This study proposes a novel approach for
assessing the hydrological value of rock glaciers in a more quantitative way
and presents exploratory results focusing on a small region. We develop an
empirical rheological model to infer ice content of rock glaciers using
readily available input data, including rock glacier planar shape, surface
slope angle, active layer thickness, and surface velocity. The model is
calibrated and validated using observational data from the Chilean Andes and
the Swiss Alps. We apply the model to five rock glaciers in the Khumbu and
Lhotse valleys, northeastern Nepal. The velocity constraints
applied to the model are derived from interferometric synthetic aperture
radar (InSAR) measurements. The volume of rock glacier is estimated based on
an existing scaling approach. The inferred volumetric ice fraction in the Khumbu
and Lhotse valleys ranges from 70 ± 8 % to 74 ± 8 %, and the
water volume equivalents lie between 1.4 ± 0.2 and 5.9±0.6×106 m3 for the coherently moving parts of individual rock glaciers.
Due to the accessibility of the model inputs, our approach is applicable to
permafrost regions where observational data are lacking, which is valuable for
estimating the water storage potential of rock glaciers in remote areas.
期刊介绍:
The Cryosphere (TC) is a not-for-profit international scientific journal dedicated to the publication and discussion of research articles, short communications, and review papers on all aspects of frozen water and ground on Earth and on other planetary bodies.
The main subject areas are the following:
ice sheets and glaciers;
planetary ice bodies;
permafrost and seasonally frozen ground;
seasonal snow cover;
sea ice;
river and lake ice;
remote sensing, numerical modelling, in situ and laboratory studies of the above and including studies of the interaction of the cryosphere with the rest of the climate system.