Aircraft measurements of wind and temperature during flight P6_231_HALO_2022_2203240601 of the HALO-AC3 campaign in 2022

During the HALO-AC3 campaign conducted in March and April 2022 in Svalbard meteorological data (temperature, 3 wind components, air pressure) have been measured in high temporal resolution (100 Hz) using instrumentation that was installed at the nosebooms of Polar 5 and Polar 6. For each flight the data are given as functions of time and position (including height above ground) along the flight tracks. All flights started and ended in Longyearbyen, Svalbard. Each file represents an entire flight starting well before the first movement of the plane and ending after the final parking position has been reached after landing. The wind measurement is only valid during flight and the full accuracy is only achieved during straight level flight sections. The absolute accuracy of the wind components is 0.5m/s for straight and level flights sections and the relative accuracy of the vertical wind speed is about 0.15m/s for straight and level flight sections. For these sections, which can be obtained on the basis of the given roll and pitch angles of the aircraft, the 100 Hz data can be used to derive turbulent fluxes of momentum and sensible heat. For further informations on the data processing and accuracy of the turbulence measurement refer to Hartmann et al. (2018, doi:10.5194/amt-11-4567-2018). The current dataset represents a downsampled version of 100Hz data to 1Hz by a moving average filter. On several occasions wind data are not available due to icing of the sensors. For those instances wind data are set to zero.

2022年3月至4月于斯瓦尔巴（Svalbard）开展的HALO-AC3科考航次中，研究人员采用安装于极地5号（Polar 5）与极地6号（Polar 6）飞机鼻锥探测吊舱（nosebooms）的观测设备，以100Hz的高时间分辨率采集了气象数据，涵盖气温、三维风场分量与大气压强。每份航次数据均以航迹沿线的时间与位置（含离地高度）为自变量进行存储。所有航次均以斯瓦尔巴的朗伊尔城（Longyearbyen）作为起降基地。每个文件对应一次完整飞行过程，涵盖飞机首次启动前至着陆后最终停稳的全时段数据。仅在飞行状态下风场测量数据有效，且仅在平直平飞阶段可达到完整测量精度。平直平飞区段的风场分量绝对精度为0.5m/s，垂直风速相对精度约为0.15m/s。依托飞机给定的滚转角与俯仰角可筛选出此类平直平飞区段，此时可利用100Hz原始数据推导动量与感热湍流通量。如需了解数据处理与湍流测量精度的更多细节，请参考Hartmann等人（2018，doi:10.5194/amt-11-4567-2018）的相关研究。本数据集为原始100Hz数据通过移动平均滤波器（moving average filter）降采样至1Hz后的版本。因传感器积冰，部分时段的风场数据不可用，此类情况下风场数据被置零。