Laser altimeter data obtained over sea-ice during the SEDNA campaign in Apr, 2007; profile SEDNA_SBLA_20070404T2318_73.79_-145.17_thr06_data_Vers5@en

Sea ice surface roughness data were obtained during the SEDNA campaign in Apr, 2007 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 (Unknown model). 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 20070404T2318. 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]海冰表面粗糙度数据采集自2007年4月的SEDNA科考航次，采用安装于电磁系统（EM-Bird）内的单波束激光高度计（Single Beam Laser Altimeter，SBLA），该系统由型号未知的直升机以距地表10~30米的高度拖曳作业。本研究采用Hibler（1972）提出的方法完成两项核心处理：a）从与飞行器运动相关的低频波动中分离出真实海面轮廓；b）识别冰脊帆状结构。具体处理流程详见https://epic.awi.de/id/eprint/56364/。本次处理设置的冰脊检测阈值为0.6米，即仅识别高度不低于0.6米的冰脊帆。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SBLA传感器为RIEGL LD90，采样率为100 Hz，传感器测量精度为5厘米，地表激光光斑直径为5.8厘米。本次特定数据集的采集时间为20070404T2318（即2007年4月4日23时18分）。数据集包含记录的高度计原始读数、推导得到的海面高程数据，以及检测到的冰脊帆的宽度、高度与间距信息。数据质量说明：5.8厘米。文件名命名规则为：[DMS/PANGAEA科考航次标识符] + [设备标识] + [日期/时间] + [经纬度] + [检测阈值] + [目标对象] + [版本号] + [文件格式]。