Mass changes in Arctic ice caps and glaciers: implications of regionalizing elevation changes
Mass changes in Arctic ice caps and glaciers: implications of regionalizing elevation changes
复制标题
北极冰盖和冰川的大规模变化：区域化海拔变化的影响
DOI：
10.5194/tc-9-139-2015
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
R. Forsberg
中科院分区：
文献类型：
--
作者：
J. Nilsson;L. Sørensen;V. Barletta;R. Forsberg
抽象的。冰川和冰帽的物质平衡对气候条件的变化很敏感。本研究中得出的质量变化是根据2003-2009年期间冰、云和陆地高程卫星（ICESat）测量的高程变化确定的。四种方法，内插和外推的基础上，用于区域化这些海拔变化的地区没有卫星覆盖。一个恒定的密度假设，然后应用到估计的质量变化，通过整合整个冰川区域。本研究的主要目的是调查北极冰盖和冰川的区域质量平衡对不同区域化方案的敏感性。敏感性分析的基础是研究质量变化的传播及其相关误差，并通过交叉验证评估不同区域化技术的适用性。交叉验证结果显示，所有区域化方法的准确性相当，但在个别地区，如斯瓦尔巴和冰岛，推断的质量变化可能高达4 Gt a−1，这超过了这些地区的估计误差约50%。这项研究进一步发现，这种传播的质量平衡是连接到海拔变化的变化幅度。这表明，在选择区划方法时应谨慎，特别是对于海拔变化差异较大的地区。
Abstract. The mass balance of glaciers and ice caps is sensitive to changing climate conditions. The mass changes derived in this study are determined from elevation changes derived measured by the Ice, Cloud, and land Elevation Satellite (ICESat) for the time period 2003–2009. Four methods, based on interpolation and extrapolation, are used to regionalize these elevation changes to areas without satellite coverage. A constant density assumption is then applied to estimate the mass change by integrating over the entire glaciated region. The main purpose of this study is to investigate the sensitivity of the regional mass balance of Arctic ice caps and glaciers to different regionalization schemes. The sensitivity analysis is based on studying the spread of mass changes and their associated errors, and the suitability of the different regionalization techniques is assessed through cross-validation. The cross-validation results shows comparable accuracies for all regionalization methods, but the inferred mass change in individual regions, such as Svalbard and Iceland, can vary up to 4 Gt a−1, which exceeds the estimated errors by roughly 50% for these regions. This study further finds that this spread in mass balance is connected to the magnitude of the elevation change variability. This indicates that care should be taken when choosing a regionalization method, especially for areas which exhibit large variability in elevation change.