摘要
低空风切变是公认的航空危险天气。为研究1.55μm激光测风雷达对低空风切变的探测能力,利用FC-Ⅲ型激光测风雷达数据对一次典型雷暴低空风切变进行细致分析。该雷达采用脉冲相干体制及全光纤结构,以混合扫描模式运行,其中包括:多普勒波束摆动(DBS)扫描、4°与6°平面位置显示(PPI)扫描、沿跑道方向的距离高度显示(RHI)扫描、03#与21#起降通道(GP)扫描。结果表明,激光测风雷达混合扫描模式可在雷暴大风天气过程中探测到低空风切变的三个阶段,即环境风引起的水平风垂直切变、阵风锋引起的水平风切变、阵风锋后部雷暴出流引起的水平风垂直切变。风切变的垂直、水平结构特征与演变过程探测清晰。利用激光测风雷达混合扫描模式,预报员可至少提前5 min对此次风切变过程进行预警。
Low-level wind shear has been recognized as one kind of dangerous weather for aviation.To study the 1.55 μm wind lidar′s detection capabilities for low-level wind shear,a typical process of low-level wind shear caused by thunderstorm gale has been analysed by using data from FC-Ⅲ wind lidar and Doppler weather radar.FC-Ⅲ wind lidar adopts pulse coherent system and all fiber structure.A combined scanning strategy was implemented to achieve detection of wind shear which includes Doppler-beam-swinging(DBS) scan,plan-position-indicator(PPI) scans at the tangles of 4-and 6-degree,range-height-indicator(RHI) scans,and glide-path(GP)scans.Results demonstrate that the combined scanning strategy can effectively detect the three stages of low-level wind shear:vertical shear of horizontal wind in the environment before the thunderstorm gale,horizontal wind shear caused by the gusty front,and vertical shear of horizontal wind caused by the gale behind the gust front.The study shows that the vertical and horizontal structure and evolution of low-level wind shear can be clearly detected during these stages.Utilizing the combined scanning strategy,forecasters can provide an early warning for this wind shear 5 minutes in advance.
作者
白寒冰
郑佳锋
杜星
车玉章
Bai Hanbing;Zheng Jiafeng;Du Xing;Che Yuzhang(Ningxia Air Traffic Management Sub-bureau,Civil Aviation Administration of China,Yinchuan 750004,Ningxia,China;College of Atmosphere Science,Chengdu University of Information Technology,Chengdu 610225,Sichuan,China)
出处
《应用激光》
CSCD
北大核心
2024年第1期86-96,共11页
Applied Laser
基金
国家自然科学基金(41905084)
民航西北空管局科技项目(201905)。
