Currently there are few observations of the urban wind field at heights other than rooftop level. Remote sensing instruments such as Doppler lidars provide wind speed data at many heights, which would be useful in determining wind loadings of tall buildings, and predicting local air quality. Studies comparing remote sensing with traditional anemometers carried out in flat, homogeneous terrain often use scan patterns which take several minutes. In an urban context the flow changes quickly in space and time, so faster scans are required to ensure little change in the flow over the scan period. We compare 3993 h of wind speed data collected using a three-beam Doppler lidar wind profiling method with data from a sonic anemometer (190 m). Both instruments are located in central London, UK; a highly built-up area. Based on wind profile measurements every 2 min, the uncertainty in the hourly mean wind speed due to the sampling frequency is 0.05–0.11 m s−1. The lidar tended to overestimate the wind speed by ≈0.5 m s−1 for wind speeds below 20 m s−1. Accuracy may be improved by increasing the scanning frequency of the lidar. This method is considered suitable for use in urban areas.
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机译：目前，除了屋顶水平以外，几乎没有观测到高空的城市风场。多普勒激光雷达等遥感仪器可提供许多高度的风速数据，这对确定高层建筑的风荷载和预测当地空气质量很有用。在平坦，均匀的地形中进行的将遥感与传统风速仪进行比较的研究经常使用扫描模式，该模式需要花费几分钟。在城市环境中，流量在空间和时间上变化很快，因此需要更快的扫描速度以确保在整个扫描期间流量几乎没有变化。我们将使用三束多普勒激光雷达风廓线法收集的3993 h风速数据与来自声速计（190 m）的数据进行比较。两种仪器均位于英国伦敦市中心；高度密集的区域。根据每2分钟进行一次风廓线测量，由于采样频率，每小时平均风速的不确定性为0.05–0.11 m s-1。对于低于20 m s-1的风速，激光雷达往往高估风速≈0.5m s-1。可以通过增加激光雷达的扫描频率来提高准确性。该方法被认为适合在城市地区使用。
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