南极岛冰盖（如图）与格陵兰岛冰盖目前都正以每年500立方千米的速度锐减，这是自20年前“卫星测高”投入使用以来所记录到的最快速度。欧洲空间局 （European Space Agency）的CryoSat-2卫星精确测量了这两块冰盖的高度数据（见图右）。数据显示，2011年与2014年间最严重的冰盖消融（见图左红色区 域）发生在南极洲西部的派恩岛冰川（Pine Island glacier）与格陵兰岛的雅各布港冰川（Jakobshavn glacier）。该数据是由位于德国波茨坦的阿尔弗雷德韦格纳研究所（Alfred Wegener Institute）的研究人员于8月20日报道的。
V. Helm, A. Humbert, and H. Miller Glaciology Section, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
Abstract.This study focuses on the present-day surface elevation of the Greenland and Antarctic ice sheets. Based on 3 years of CryoSat-2 data acquisition we derived new elevation models (DEMs) as well as elevation change maps and volume change estimates for both ice sheets. Here we present the new DEMs and their corresponding error maps. The accuracy of the derived DEMs for Greenland and Antarctica is similar to those of previous DEMs obtained by satellite-based laser and radar altimeters. Comparisons with ICESat data show that 80% of the CryoSat-2 DEMs have an uncertainty of less than 3 m ± 15 m. The surface elevation change rates between January 2011 and January 2014 are presented for both ice sheets. We compared our results to elevation change rates obtained from ICESat data covering the time period from 2003 to 2009. The comparison reveals that in West Antarctica the volume loss has increased by a factor of 3. It also shows an anomalous thickening in Dronning Maud Land, East Antarctica which represents a known large-scale accumulation event. This anomaly partly compensates for the observed increased volume loss of the Antarctic Peninsula and West Antarctica. For Greenland we find a volume loss increased by a factor of 2.5 compared to the ICESat period with large negative elevation changes concentrated at the west and southeast coasts. The combined volume change of Greenland and Antarctica for the observation period is estimated to be ？503 ± 107 km3yr？1. Greenland contributes nearly 75% to the total volume change with ？375 ± 24 km3yr？1.
Citation:Helm, V., Humbert, A., and Miller, H.: Elevation and elevation change of Greenland and Antarctica derived from CryoSat-2, The Cryosphere, 8, 1539-1559, doi:10.5194/tc-8-1539-2014, 2014.
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《Nature》新闻一周热点-南极冰盖迅速消融
南极岛冰盖（如图）与格陵兰岛冰盖目前都正以每年500立方千米的速度锐减，这是自20年前“卫星测高”投入使用以来所记录到的最快速度。欧洲空间局 （European Space Agency）的CryoSat-2卫星精确测量了这两块冰盖的高度数据（见图右）。数据显示，2011年与2014年间最严重的冰盖消融（见图左红色区 域）发生在南极洲西部的派恩岛冰川（Pine Island glacier）与格陵兰岛的雅各布港冰川（Jakobshavn glacier）。该数据是由位于德国波茨坦的阿尔弗雷德韦格纳研究所（Alfred Wegener Institute）的研究人员于8月20日报道的。
新闻链接：http://www.nature.com/news/seven-days-22-28-august-2014-1.15767Elevation and elevation change of Greenland and Antarctica derived from CryoSat-2V. Helm, A. Humbert, and H. Miller
Glaciology Section, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
Abstract. This study focuses on the present-day surface elevation of the Greenland and Antarctic ice sheets. Based on 3 years of CryoSat-2 data acquisition we derived new elevation models (DEMs) as well as elevation change maps and volume change estimates for both ice sheets. Here we present the new DEMs and their corresponding error maps. The accuracy of the derived DEMs for Greenland and Antarctica is similar to those of previous DEMs obtained by satellite-based laser and radar altimeters. Comparisons with ICESat data show that 80% of the CryoSat-2 DEMs have an uncertainty of less than 3 m ± 15 m. The surface elevation change rates between January 2011 and January 2014 are presented for both ice sheets. We compared our results to elevation change rates obtained from ICESat data covering the time period from 2003 to 2009. The comparison reveals that in West Antarctica the volume loss has increased by a factor of 3. It also shows an anomalous thickening in Dronning Maud Land, East Antarctica which represents a known large-scale accumulation event. This anomaly partly compensates for the observed increased volume loss of the Antarctic Peninsula and West Antarctica. For Greenland we find a volume loss increased by a factor of 2.5 compared to the ICESat period with large negative elevation changes concentrated at the west and southeast coasts. The combined volume change of Greenland and Antarctica for the observation period is estimated to be ？503 ± 107 km3 yr？1. Greenland contributes nearly 75% to the total volume change with ？375 ± 24 km3 yr？1.
Citation: Helm, V., Humbert, A., and Miller, H.: Elevation and elevation change of Greenland and Antarctica derived from CryoSat-2, The Cryosphere, 8, 1539-1559, doi:10.5194/tc-8-1539-2014, 2014.
论文链接：http://www.the-cryosphere.net/8/1539/2014/tc-8-1539-2014.html