Surface elevations on Qaanaaq and Bowdoin Glaciers in northwestern Greenland as measured by a kinematic GPS survey from 2012-2016

Kinematic GPS measurements provide in-situ data crucial for measuring the surface elevation change of glaciers. Owing to their accuracy, which is generally better than half meter, surface elevations derived from kinematic GPS surveys are useful and essential for generating precise digital elevation models (DEMs) and evaluating geometry changes of glaciers. We present a surface elevation data set derived from kinematic GPS measurements covering the lower 5 km of Qaanaaq and Bowdoin Glaciers in northwestern Greenland. The data includes elevations over ice-free terrain nearby the glaciers, important for calibrating remote sensing data. More than 600,000 GPS survey data points were processed to produce a 1-m resolution mesh grid of elevation data in a CSV file format. Based on our error analysis, the accuracies of the elevation data are better than 0.2 and 0.3 m in horizontal and vertical directions, respectively. This dataset can be utilized to investigate glacier surface elevation changes by comparing it making comparison with DEMs that may be obtained in the past, and from future from remote sensing and in-situ observations.

动态GPS（Kinematic GPS）测量可提供原位观测数据，该数据对冰川表面高程变化的监测至关重要。得益于其通常优于0.5米的测量精度，由动态GPS测量得到的冰川表面高程数据，对于构建高精度数字高程模型（Digital Elevation Models, DEMs）以及评估冰川几何形态变化具有不可或缺的重要价值。本研究提供一套基于动态GPS测量的表面高程数据集，覆盖格陵兰西北部卡纳克（Qaanaaq）冰川与鲍登（Bowdoin）冰川下游5千米范围。该数据集包含冰川周边无冰区域的高程数据，可用于遥感数据的校准工作，具有重要应用价值。研究共处理了超过60万个GPS测量数据点，最终生成分辨率为1米的高程网格数据，并以CSV文件格式存储。经误差分析验证，该高程数据的水平与垂直方向精度分别优于0.2米与0.3米。本数据集可通过与过往及未来通过遥感与原位观测获取的数字高程模型进行对比，用于探究冰川表面高程的变化特征。