气候变化领域集成服务门户(CCPortal): Surface motion of active rock glaciers in the Sierra Nevada, California, USA: Inventory and a case study using InSAR

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DOI	10.5194/tc-7-1109-2013
	Surface motion of active rock glaciers in the Sierra Nevada, California, USA: Inventory and a case study using InSAR
	Liu L.; Millar C.I.; Westfall R.D.; Zebker H.A.
发表日期	2013
ISSN	19940416
卷号	7 期号:4
英文摘要	Despite the abundance of rock glaciers in the Sierra Nevada of California, USA, few efforts have been made to measure their surface flow. Here we use the interferometric synthetic aperture radar (InSAR) technique to compile a benchmark inventory describing the kinematic state of 59 active rock glaciers in this region. In the late summer of 2007, these rock glaciers moved at speeds that range from 14 cm yr−1 to 87 cm yr−1, with a regional mean value of 53 cm yr−1. Our inventory reveals a spatial difference: rock glaciers in the southern Sierra Nevada moved faster than the ones in the central Sierra Nevada. In addition to the regional mapping, we also conduct a case study to measure the surface flow of the Mount Gibbs rock glacier in fine spatial and temporal detail. The InSAR measurements over this target reveal (1) that the spatial pattern of flow is correlated with surface geomorphic features and (2) a significant seasonal variation of flow speed whose peak value was 48 cm yr−1in the fall of 2007, more than twice the minimum value observed in the spring of 2008. The seasonal variation lagged air temperatures by three months. Our finding on the seasonal variation of surface speed reinforces the importance of a long time series with high temporal sampling rates to detect possible long-term changes of rock glacier kinematics in a warming climate. © Author(s) 2013.
学科领域	air temperature; flow velocity; glacier dynamics; glacier flow; inventory; rock glacier; seasonal variation; spatial analysis; synthetic aperture radar; time series; California; Sierra Nevada [California]; United States
语种	英语
scopus关键词	air temperature; flow velocity; glacier dynamics; glacier flow; inventory; rock glacier; seasonal variation; spatial analysis; synthetic aperture radar; time series; California; Sierra Nevada [California]; United States
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/120264
作者单位	Department of Geophysics, Stanford University, Stanford, CA, United States; USDA Forest Service, Pacific Southwest Research Station, Albany, CA, USA, United States
推荐引用方式 GB/T 7714	Liu L.,Millar C.I.,Westfall R.D.,et al. Surface motion of active rock glaciers in the Sierra Nevada, California, USA: Inventory and a case study using InSAR[J],2013,7(4).
APA	Liu L.,Millar C.I.,Westfall R.D.,&Zebker H.A..(2013).Surface motion of active rock glaciers in the Sierra Nevada, California, USA: Inventory and a case study using InSAR.Cryosphere,7(4).
MLA	Liu L.,et al."Surface motion of active rock glaciers in the Sierra Nevada, California, USA: Inventory and a case study using InSAR".Cryosphere 7.4(2013).