Laser altimeter data obtained over sea-ice during the Transdrift-XIII campaign in Apr-May, 2008; profile Transdrift-XIII_SBLA_20080414T0641_74.74_129.41_thr06_data_Vers5@en

Sea ice surface roughness data were obtained during the Transdrift-XIII campaign in Apr-May, 2008 with a Single Beam Laser Altimeter (SBLA) mounted inside an electromagnetic system (EM-Bird) towed at 10-30 m height above surface by a Helicopter (Mil MI-8). A method developed by Hibler (1972) was used to a) isolate the surface profile from low-frequency variations associated with the aircraft motion and b) to identify pressure ridge sails. The processing steps are described in https://epic.awi.de/id/eprint/56364/. We applied a ridge detection threshold of 0.6 m, which means that only sails higher 0.6 m are detected. Version and name of the processing routine: Laser_Altimeter_Processing_VS5_06_20.py (vers.5, Feb 22, 2024, https://gitlab.awi.de/sitem/sbla_processing.git). SBLA records (RIEGL - LD90) are provided at a sampling rate of 100 Hz. Sensor accuracy is 5 cm with a beam diameter at surface of 5.8 cm. This specific dataset was obtained on 20080414T0641. It includes recorded altimeter readings, the derived surface elevation and width/height/spacing of detected pressure ridge sails. Note on data quality: 5.8 cm . File name: [DMS/PANGAEA Campaing Identifier] + [DEVICE] + [DATE/TIME] + [LAT/LON] + [Detection Threshold] + [Object] + [Version] + [Format]本数据集的海冰表面粗糙度数据采集于2008年4—5月实施的Transdrift-XIII科考航次，由搭载于电磁系统（EM-Bird）内的单波束激光高度计（Single Beam Laser Altimeter，SBLA）完成采集，该系统由米里-8（Mil MI-8）直升机以10~30米的地表高度拖曳作业。 研究采用Hibler于1972年提出的处理方法完成两项核心任务：a）分离出与飞行器运动相关的低频分量对应的地表剖面；b）识别冰面压力脊帆结构。具体处理流程详见https://epic.awi.de/id/eprint/56364/。 本次处理采用0.6米的脊线检测阈值，即仅可检测出高度不低于0.6米的冰帆结构。所用处理程序的版本与名称为：Laser_Altimeter_Processing_VS5_06_20.py（版本5，2024年2月22日，代码仓库地址：https://gitlab.awi.de/sitem/sbla_processing.git）。 本次使用的单波束激光高度计（SBLA）型号为RIEGL LD90，采样率为100 Hz。该传感器的测量精度为5厘米，地表激光光斑直径为5.8厘米。 本数据集的具体采集时刻为2008年4月14日06时41分（标识为20080414T0641），包含记录的高度计原始读数、反演得到的地表高程数据，以及检测得到的冰面压力脊帆的宽度、高度与间距信息。 数据质量说明：5.8厘米。 数据集文件命名规则为：[DMS/PANGAEA科考航次标识符] + [设备名称] + [日期/时间] + [经纬度] + [检测阈值] + [目标对象] + [版本号] + [文件格式]