DOI: 10.5194/tc-7-1247-2013
Scopus记录号: 2-s2.0-84881500651
论文题名: Hoar crystal development and disappearance at Dome C, Antarctica: Observation by near-infrared photography and passive microwave satellite
作者: Champollion N ; , Picard G ; , Arnaud L ; , Lefebvre E ; , Fily M
刊名: Cryosphere
ISSN: 19940416
出版年: 2013
卷: 7, 期: 4 起始页码: 1247
结束页码: 1262
语种: 英语
英文关键词: air-snow interaction
; algorithm
; cryosphere
; energy budget
; hoar frost
; observational method
; photography
; polarization
; satellite data
; snow cover
; time series
; Antarctica
; Dome Concordia
; East Antarctica
英文摘要: Hoar crystals episodically cover the snow surface in Antarctica and affect the roughness and reflective properties of the air-snow interface. However, little is known about their evolution and the processes responsible for their development and disappearance despite a probable influence on the surface mass balance and energy budget. To investigate hoar evolution, we use continuous observations of the surface by in situ near-infrared photography and by passive microwave remote sensing at Dome C in Antarctica. From the photography data, we retrieved a daily indicator of the presence/absence of hoar crystals using a texture analysis algorithm. The analysis of this 2 yr long time series shows that Dome C surface is covered almost half of the time by hoar. The development of hoar crystals takes a few days and seems to occur whatever the meteorological conditions. In contrast, the disappearance of hoar is rapid (a few hours) and coincident with either strong winds or with moderate winds associated with a change in wind direction from southwest (the prevailing direction) to southeast. From the microwave satellite data, we computed the polarisation ratio (i.e. horizontal over vertical polarised brightness temperatures), an indicator known to be sensitive to hoar in Greenland. Photography data and microwave polarisation ratio are correlated, i.e. high values of polarisation ratio which theoretically correspond to low snow density values near the surface are associated with the presence of hoar crystals in the photography data. Satellite data over nearly ten years (2002-2011) confirm that a strong decrease of the polarisation ratio (i.e. signature of hoar disappearance) is associated with an increase of wind speed or a change in wind direction from the prevailing direction. The photography data provides, in addition, evidence of interactions between hoar and snowfall. Further adding the combined influence of wind speed and wind direction results in a complex picture of the snow-atmosphere interactions in Antarctica which deserves further quantification and modelling. © 2013 Author(s). Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/74967
Appears in Collections: 影响、适应和脆弱性 气候变化与战略
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作者单位: UJF - Grenoble 1, CNRS, Laboratoire de Glaciologie et Géophysique de Lenvironnement (LGGE) UMR5183, Grenoble, 38041, France
Recommended Citation:
Champollion N,, Picard G,, Arnaud L,et al. Hoar crystal development and disappearance at Dome C, Antarctica: Observation by near-infrared photography and passive microwave satellite[J]. Cryosphere,2013-01-01,7(4)