Drill hole measurements of fast ice and sub-ice platelet layer thickness, and snow depth in McMurdo Sound - November 2018

Here, we present drill hole measurements carried out at 14 field sites distributed over a ~1500 km^2 area of fast ice in the south of McMurdo Sound, Antarctica between 1 and 19 November 2018. At each site, five holes were drilled in the fast ice at the centre and end points of two cross‐profile lines, each 30 metre long. Sea ice and SIPL thicknesses were measured with a suspended thickness probe and metal bar using the procedure described in Price et al. (2014). Snow depth measurements at centimetre accuracy were made at half‐metre intervals along the cross‐profiles using a metal ruler or a GPS‐equipped Magnaprobe. Sea ice freeboard (i.e., the height of the sea ice surface above sea level) was measured in each of the drill holes. The average value for each parameter was calculated at each field site to provide a representative measurement over the 30 metre cross-profile fast ice area. The drill hole measurements were used to underpin spatial distribution surveys of the aforementioned parameters, to inform electromagnetic induction forward and inverse models, and to ground-validate satellite altimetry assessments of fast ice freeboard and derived ice thickness in McMurdo Sound.

本数据集收录了2018年11月1日至19日，在南极洲麦克默多湾南部约1500平方千米的固定冰（fast ice）区域内14个野外测点开展的钻孔测量数据。每个测点在固定冰上，沿两条各长30米的剖面线的中心点与端点位置钻取5个钻孔。采用悬挂式厚度探头与金属杆，参照Price等人（2014）的实验方法，测量海冰与SIPL厚度。沿剖面线以半米为间隔，使用金属直尺或配备GPS的Magnaprobe，开展精度达厘米级的雪深测量。在每个钻孔中测量海冰干舷，即海冰表面相对于海平面的高度。针对每个测点计算各参数的平均值，以表征该30米剖面固定冰区域的典型测量结果。本钻孔测量数据可用于支撑上述参数的空间分布调查，为电磁感应正演与反演模型提供依据，并对麦克默多湾固定冰干舷及反演得到的海冰厚度的卫星测高评估开展地面验证。