DOI: 10.5194/tc-8-705-2014
Scopus记录号: 2-s2.0-84899046697
论文题名: Uncertainties in Arctic sea ice thickness and volume: New estimates and implications for trends
作者: Zygmuntowska M ; , Rampal P ; , Ivanova N ; , Smedsrud L ; H
刊名: Cryosphere
ISSN: 19940416
出版年: 2014
卷: 8, 期: 2 起始页码: 705
结束页码: 720
语种: 英语
英文关键词: CryoSat-2
; cryosphere
; ice thickness
; ICESat
; sea ice
; seasonality
; snow cover
; trend analysis
; uncertainty analysis
; volume
; Arctic Ocean
英文摘要: Sea ice volume has decreased in the last decades, evoked by changes in sea ice area and thickness. Estimates of sea ice area and thickness rely on a number of geophysical parameters which introduce large uncertainties. To quantify these uncertainties we use freeboard retrievals from ICESat and investigate different assumptions about snow depth, sea ice density and area. We find that uncertainties in ice area are of minor importance for the estimates of sea ice volume during the cold season in the Arctic basin. The choice of mean ice density used when converting sea ice freeboard into thickness mainly influences the resulting mean sea ice thickness, while snow depth on top of the ice is the main driver for the year-to-year variability, particularly in late winter. The absolute uncertainty in the mean sea ice thickness is 0.28 m in February/March and 0.21 m in October/November. The uncertainty in snow depth contributes up to 70% of the total uncertainty and the ice density 30-35%, with higher values in October/November. We find large uncertainties in the total sea ice volume and trend. The mean total sea ice volume is 10 120 ± 1280 km3 in October/November and 13 250 ± 1860 km3 in February/March for the time period 2005-2007. Based on these uncertainties we obtain trends in sea ice volume of −1450 ± 530 km3 a−1 in October/November and −880 ± 260 km3 a−1 in February/March over the ICESat period (2003-2008). Our results indicate that, taking into account the uncertainties, the decline in sea ice volume in the Arctic between the ICESat (2003-2008) and CryoSat-2 (2010-2012) periods may have been less dramatic than reported in previous studies. However, more work and validation is required to quantify these changes and analyse possible unresolved biases in the freeboard retrievals. © Author(s) 2014. CC Attribution 3.0 License. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/74859
Appears in Collections: 影响、适应和脆弱性 气候变化与战略
There are no files associated with this item.
作者单位: Nansen Environmental and Remote Sensing Center, Bergen, Norway; Geophysical Institute, University of Bergen, Bergen, Norway
Recommended Citation:
Zygmuntowska M,, Rampal P,, Ivanova N,et al. Uncertainties in Arctic sea ice thickness and volume: New estimates and implications for trends[J]. Cryosphere,2014-01-01,8(2)