Annual surface flow velocity on Qaanaaq ice cap, Greenland in 2018-2019

The surface motion of the glacier was measured by surveying 6 stakes (1.5-2.0 m long aluminium poles) installed in the ice of Qaanaaq ice cap. Dual-frequency GPS receivers and antennas (GNSS GEM-1) were used to measure the three-dimensional positions of the stakes. One antenna was fixed on the roof of Qaanaaq Club House as a reference station. At Q1701-Q1706, the antennae were mounted on the stakes and operated for more than 30 minutes in August 2018 and July, August 2019. These data were processed in static mode by the GPS software (RTKLIB, Leica Geo Office) Office to compute the position of the stakes. Measurement errors were estimated below 10 mm.本数据集通过对卡纳阿克冰盖（Qaanaaq Ice Cap）冰面布设的6根铝制测桩（长1.5~2.0米）开展外业测量，获取冰川表面运动相关数据。采用双频GPS接收机与GNSS GEM-1型天线，测定各测桩的三维位置；将一台天线固定于卡纳阿克俱乐部屋顶作为基准站。针对编号为Q1701至Q1706的测桩，于2018年8月及2019年7、8月将天线安装于测桩上开展观测，单次观测时长均超过30分钟。采用GPS解算软件（RTKLIB、Leica Geo Office）以静态模式对上述观测数据进行处理，解算出各测桩的位置坐标。经估算，本次测量的点位误差小于10毫米。