Antarctica on the scales: Present-day mass balance of the Antarctic Peninsula from time-variable gravity field measurements

尺度上的南极洲：根据时变重力场测量得出的南极半岛当今的质量平衡

• 批准号: NE/C002121/1
• 负责人: Matt King
• 金额: $ 19.71万
• 依托单位: Newcastle University
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2006
• 资助国家: 英国
• 起止时间: 2006 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FC002121%2F1
• 关键词: Antarctica; scales; Present; day; mass

The subject of this study is the present-day ice mass balance of the Antarctic Peninsula using time-variable gravity measurements from the Gravity Recovery and Climate Experiment (GRACE) complemented by data from in situ GPS sites and altimetric missions such as EnviSat, CyroSat and ICESat. This region is amongst the fastest warming regions on Earth and dramatic changes have been occurring over the past few decades, including the complete collapse of several ice shelves. Every 30 days GRACE delivers a gravity field with information at spatial scales down to ~400 km, with an accuracy approaching 2 cm of water. Over Antarctica GRACE will capture ice mass changes, although these will be contaminated by mass variations in the atmosphere, in nearby oceans, and due to post-glacial rebound (PGR) in the solid earth. Due to its relative ease of access, the Antarctic Peninsula is relatively well-known as regards atmospheric pressure and oceanic mass variations although numerical ocean tide models are still largely unverified in this region and errors will alias into the GRACE time series. The research will therefore focus on i) PGR measurements using new and existing Global Positioning System (GPS) observations to constrain rebound models; ii) verification of numerical tide models using onshore GPS ocean tide loading deformation estimates followed by application to the GRACE time series; and iii) the determination of seasonal and secular rates of ice mass change using corrected GRACE measurements; with iv) enhancement from radar and laser altimetry as appropriate. These will provide independent constraints on the effects of a warming climate on the Antarctic continent.

这项研究的主题是南极半岛目前的冰量平衡，利用重力恢复和气候实验的时变重力测量结果，辅之以来自全球定位系统现场和EnviSat、CyroSat和ICESat等测高飞行任务的数据。该地区是地球上变暖最快的地区之一，在过去的几十年里发生了巨大的变化，包括几个冰架的完全崩溃。GRACE每30天提供一个重力场，其空间尺度可达400公里，精度接近2厘米水。在南极洲上空，GRACE将捕捉到冰的质量变化，尽管这些变化会受到大气、附近海洋和固体地球冰后反弹（PGR）的质量变化的影响。由于其相对容易进入，南极半岛是相对知名的大气压力和海洋质量的变化，虽然数值海洋潮汐模型仍然在很大程度上未经验证，在这一地区和错误将混叠到GRACE时间序列。因此，研究将侧重于：一）利用新的和现有的全球定位系统观测结果进行PGR测量，以约束回弹模型;二）利用陆上全球定位系统海潮负荷变形估计值验证数值潮汐模型，然后应用于GRACE时间序列;三）利用经校正的GRACE测量结果确定季节性和长期性冰量变化率;（iv）视乎情况，加强雷达和激光测高。这些将对气候变暖对南极大陆的影响提供独立的限制。

项目成果

A comparison of GPS, VLBI and model estimates of ocean tide loading displacements

• DOI: 10.1007/s00190-006-0118-9
• 发表时间: 2006-12
• 期刊: Journal of Geodesy
• 影响因子: 4.4
• 作者: I. Thomas;Matt A. King;P. Clarke