DOI: 10.5194/tc-14-4323-2020
论文题名: Local-scale variability of snow density on Arctic sea ice
作者: King J. ; Howell S. ; Brady M. ; Toose P. ; Derksen C. ; Haas C. ; Beckers J.
刊名: Cryosphere
ISSN: 19940416
出版年: 2020
卷: 14, 期: 12 起始页码: 4323
结束页码: 4339
语种: 英语
英文关键词: autocorrelation
; bulk density
; error analysis
; estimation method
; model validation
; parameterization
; radar altimetry
; sea ice
; separation
; snowpack
; spatial analysis
; supervised classification
; Arctic Ocean
; Canada
; Canadian Arctic
英文摘要: Local-scale variations in snow density and layering on Arctic sea ice were characterized using a combination of traditional snow pit and SnowMicroPen (SMP) measurements. In total, 14 sites were evaluated within the Canadian Arctic Archipelago and Arctic Ocean on both first-year (FYI) and multi-year (MYI) sea ice. Sites contained multiple snow pits with coincident SMP profiles as well as unidirectional SMP transects. An existing SMP density model was recalibrated using manual density cutter measurements (n D 186) to identify best-fit parameters for the observed conditions. Cross-validation of the revised SMP model showed errors comparable to the expected baseline for manual density measurements (RMSED34 kgm3 or 10.9 %) and strong retrieval skill (R2 D0.78). The density model was then applied to SMP transect measurements to characterize variations at spatial scales of up to 100 m. A supervised classification trained on snow pit stratigraphy allowed separation of the SMP density estimates by layer type. The resulting dataset contains 58 882 layer-classified estimates of snow density on sea ice representing 147m of vertical variation and equivalent to more than 600 individual snow pits. An average bulk density of 310 kgm3 was estimated with clear separation between FYI and MYI environments. Lower densities on MYI (277 kgm3) corresponded with increased depth hoar composition (49.2 %), in strong contrast to composition of the thin FYI snowpack (19.8 %). Spatial autocorrelation analysis showed layered composition on FYI snowpack to persist over long distances while composition on MYI rapidly decorrelated at distances less than 16 m. Application of the SMP profiles to determine propagation bias in radar altimetry showed the potential errors of 0.5 cm when climatology is used over known snow density. © 2020 BMJ Publishing Group. All rights reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/164505
Appears in Collections: 气候变化与战略
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作者单位: Climate Research Division, Environment and Climate Change Canada, Toronto, M3H5T4, Canada; Alfred Wegener Institute of Polar and Marine Research, Bremerhaven, Germany; Canadian Forest Service, Natural Resources Canada, Edmonton, T6H 3S5, Canada; Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, T6G2E3, Canada
Recommended Citation:
King J.,Howell S.,Brady M.,et al. Local-scale variability of snow density on Arctic sea ice[J]. Cryosphere,2020-01-01,14(12)