Analysis of East Antarctic drainage basins with altimetric, interferometric, gravity and GPS techniques to determine their state of flux

Metadata record for data from ASAC Project 2788See the link below for public details on this project. Public This project will reassess the mass balance of Law Dome and a large sector of the Antarctic ice sheet south of Casey by exploiting the time history of change that can be obtained by resurveying historical surface elevation and gravity networks, started in the 1960s. The changes in position and gravity from these terrestrial traverses act as important constraints and, in some cases, calibration for recent satellite altimeter missions. Such a reassessment and model improvement should see a significant drop in the current uncertainty of the contribution of the Antarctic ice sheet to global sea level rise. 2007-2008 Season:Historical and recent data over Law Dome has been successfully re-reduced and integrated with recent satellite data over a period spanning 1962 to 2005. These data show that the surface elevation of Law Dome decreased from 1962 to about 1971 and then generally increased till 2005 indicating that ice volumes have recently varied over decadal time spans. The variations that are present within our gravity data set are in agreement with the deep core stratigraphy results from the Law Dome summit. Since our data cover the full extent of Law Dome, we are able to state with good confidence that the changes we see are consistent with climate-related signals where increased precipitation is due to increased atmospheric water vapour. This phenomenon has been reported in the Norwegian Arctic. The detection of these localised complex changes, over decadal time scales , highlights problems associated with interpreting relatively short time scale altimetric measurements.

本数据集的元数据记录来自ASAC项目2788号。有关该项目的公开详情，请参阅下方链接。
本项目为公开项目，将通过对始于1960年代的历史地表高程与重力测量网进行复测，获取变化时间序列，以此重新评估劳冰穹（Law Dome）以及凯西站以南大片南极冰盖的物质平衡。这些地面测量剖面所得到的点位与重力变化数据，可为近期的卫星测高任务提供重要约束条件，在部分场景下还可作为校准依据。此类重新评估与模型优化工作，有望大幅降低当前南极冰盖对全球海平面上升贡献量的估算不确定性。
2007-2008年度科考季：针对劳冰穹的历史与近期观测数据已成功完成重新归算，并与1962年至2005年期间的卫星观测数据完成整合。数据显示，劳冰穹的地表高程在1962年至1971年左右呈下降趋势，随后总体回升至2005年，这表明冰体体积近年来以十年为时间跨度发生波动。本次重力数据集内观测到的变化，与劳冰穹峰顶的深冰芯地层学研究结果相符。由于本次观测数据覆盖了劳冰穹的全域，我们可以较为自信地指出，观测到的变化与气候相关信号一致：即大气水汽含量增加导致降水增多。该现象已在挪威北极地区被观测报道。在十年时间尺度上探测到这类局域性复杂变化，也凸显了对较短时间尺度测高数据进行解译时存在的相关问题。