Low-Level Wind Shear Identification along the Glide Path at BCIA by the Pulsed Coherent Doppler Lidar

Low-level wind shear is usually to be a rapidly changing meteorological phenomenon that cannot be ignored in aviation security service by affecting the air speed of landing and take-off aircrafts. The lidar team in Ocean University of China (OUC) carried out the long term particular researches on the low-level wind shear identification and regional wind shear inducement search at Beijing Capital International Airport (BCIA) from 2015 to 2020 by operating several pulsed coherent Doppler lidar (PCDL) systems. On account of the improved glide path scanning strategy and virtual multiple wind anemometers based on the rang height indicator (RHI) modes, the small-scale meteorological phenomenon along the glide path and/or runway center line direction can be captured. In this paper, the device configuration, scanning strategies, and results of the observation data are proposed. The algorithms to identify the low-level wind shear based on the reconstructed headwind profiles data have been tested and proved based on the lidar data obtained from December 2018 to January 2019. High spatial resolution observation data at vertical direction are utilized to study the regional wind shear inducement at the 36L end of BCIA under strong northwest wind conditions.

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Airport low-level wind shear lidar observation at beijing capital international airport

EPJ Web of Conferences ◽

10.1051/epjconf/201817606013 ◽

2018 ◽

Vol 176 ◽

pp. 06013

Author(s):

Hongwei Zhang ◽

Songhua Wu ◽

Qichao Wang ◽

Bingyi Liu ◽

Xiaochun Zhai

Keyword(s):

Wind Shear ◽

Doppler Lidar ◽

Low Level ◽

Lidar Observation ◽

International Airport ◽

Glide Path ◽

Coherent Doppler Lidar

Ocean University of China lidar team operated a pulse coherent Doppler lidar (PCDL) for the low level wind shear monitoring at the Beijing Capital International Airport (BCIA) in 2015. The experiment configuration, observation modes is presented. A case study shows that the low level wind shear events at the southern end of 18R/36L runway were mainly caused by the trees and buildings along the glide path under strong northwest wind conditions.

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Detection of Complex Terrain-Induced Wind Shear by Doppler Lidar at Beijing Capital International Airport

EPJ Web of Conferences ◽

10.1051/epjconf/202023706004 ◽

2020 ◽

Vol 237 ◽

pp. 06004

Author(s):

Xiaoying Liu ◽

Songhua Wu ◽

Hongwei Zhang ◽

Jianjun Zhang ◽

Zhiqiang He ◽

...

Keyword(s):

Wind Field ◽

Complex Terrain ◽

Wind Shear ◽

Field Structure ◽

Shielding Effect ◽

Doppler Lidar ◽

Wake Effect ◽

International Airport ◽

Glide Path ◽

Coherent Doppler Lidar

In November 2018, the lidar-based wind shear synchronous experiment was performed at Beijing Capital International Airport (BCIA). In this experiment, aiming at the measurement of the terrain-induced wind shear and the wind field around the runway, the glide path scanning mode, and the RHI strategy were conducted alternately. Radial velocity retrieved from the glide path scanning can obviously present the wakes caused by complex terrain (e.g., hills, tall trees, residential and terminal buildings). The Pulse Coherent Doppler Lidar (PCDL) warned the terrain-induced wind shear, which was verified by the pilot report. The wind field structure around the runway under the wake effect and the building shielding effect is also analyzed.

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Applications of an Infrared Doppler Lidar in Detection of Wind Shear

Journal of Atmospheric and Oceanic Technology ◽

10.1175/2007jtecha1057.1 ◽

2008 ◽

Vol 25 (5) ◽

pp. 637-655 ◽

Cited By ~ 72

Author(s):

C. M. Shun ◽

P. W. Chan

Keyword(s):

Hong Kong ◽

Wind Shear ◽

Spatial And Temporal Variability ◽

Doppler Lidar ◽

Glide Path ◽

Alerting System ◽

Hong Kong International Airport ◽

Detection Technologies ◽

Gust Front ◽

Glide Paths

Abstract In December 2005, operational wind shear alerting at the Hong Kong International Airport (HKIA) reached an important milestone with the launch of the automatic Lidar (light detection and ranging) Windshear Alerting System (LIWAS). This signifies that the anemometer-based and radar-based wind shear detection technologies deployed worldwide in the twentieth century have been further advanced by the addition of the lidar—a step closer to all-weather coverage. Unlike the microburst and gust front, which have a well-defined coherent vertical structure in the lowest several hundred meters of the atmosphere, terrain-induced wind shear tends to have high spatial and temporal variability. To detect the highly changeable winds to be encountered by the aircraft under terrain-induced wind shear situations, the Hong Kong Observatory devises an innovative glide path scan (GPScan) strategy for the lidar, pointing the laser beam toward the approach and departure glide paths, with the changes in azimuth and elevation angles concerted. The purpose of the GPScans is to derive the headwind profiles and hence the wind shear along the glide paths. Developed based on these GPScans, LIWAS is able to capture about 76% of the wind shear events reported by pilots over the most-used approach corridor under clear-air conditions. During the past two years, further developments of the lidar took place at HKIA, including the use of runway-specific lidar to further enhance the wind shear detection performance.

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Mixed layer depths via Doppler lidar during low-level jet events

EPJ Web of Conferences ◽

10.1051/epjconf/201817606017 ◽

2018 ◽

Vol 176 ◽

pp. 06017

Author(s):

Brian Carroll ◽

Belay Demoz ◽

Timothy Bonin ◽

Ruben Delgado

Keyword(s):

Fuzzy Logic ◽

Wind Speed ◽

Mixed Layer ◽

Wind Shear ◽

Lower Troposphere ◽

Doppler Lidar ◽

High Wind ◽

Fuzzy Logic Algorithm ◽

Low Level ◽

Low Level Jet

A low-level jet (LLJ) is a prominent wind speed peak in the lower troposphere. Nocturnal LLJs have been shown to transport and mix atmospheric constituents from the residual layer down to the surface, breaching quiescent nocturnal conditions due to high wind shear. A new fuzzy logic algorithm combining turbulence and aerosol information from Doppler lidar scans can resolve the strength and depth of this mixing below the jet. Conclusions will be drawn about LLJ relations to turbulence and mixing.

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Coherent Doppler lidar signal covariance including wind shear and wind turbulence

Applied Optics ◽

10.1364/ao.33.006472 ◽

1994 ◽

Vol 33 (27) ◽

pp. 6472 ◽

Cited By ~ 24

Author(s):

Rod Frehlich

Keyword(s):

Wind Shear ◽

Doppler Lidar ◽

Lidar Signal ◽

Coherent Doppler Lidar ◽

Wind Turbulence

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Small-scale high wind cores enhancing low-level wind shear: Doppler radar observation of opposing wind adjacent to the sea-breeze frontal zone on 20 September 1989

Meteorology and Atmospheric Physics ◽

10.1007/bf01031873 ◽

1993 ◽

Vol 52 (3-4) ◽

pp. 147-152

Author(s):

H. Ohno ◽

O. Suzuki

Keyword(s):

Wind Shear ◽

Doppler Radar ◽

Frontal Zone ◽

Sea Breeze ◽

Radar Observation ◽

Small Scale ◽

High Wind ◽

Low Level

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Properties of the offshore low level jet and rotor layer wind shear as measured by scanning Doppler Lidar

Wind Energy ◽

10.1002/we.2075 ◽

2016 ◽

Vol 20 (6) ◽

pp. 987-1002 ◽

Cited By ~ 13

Author(s):

Y. L. Pichugina ◽

W. A. Brewer ◽

R. M. Banta ◽

A. Choukulkar ◽

C. T. M. Clack ◽

...

Keyword(s):

Wind Shear ◽

Doppler Lidar ◽

Low Level ◽

Low Level Jet

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Long-lived high-frequency gravity waves in the atmospheric boundary layer: observations and simulations

Atmospheric Chemistry and Physics ◽

10.5194/acp-19-15431-2019 ◽

2019 ◽

Vol 19 (24) ◽

pp. 15431-15446 ◽

Cited By ~ 2

Author(s):

Mingjiao Jia ◽

Jinlong Yuan ◽

Chong Wang ◽

Haiyun Xia ◽

Yunbin Wu ◽

...

Keyword(s):

Boundary Layer ◽

Atmospheric Boundary Layer ◽

Gravity Waves ◽

Horizontal Wind ◽

Doppler Lidar ◽

Low Level ◽

Coherent Doppler Lidar ◽

Computational Fluid Dynamics Cfd ◽

Phase Progression ◽

Low Level Jet

Abstract. A long-lived gravity wave (GW) in the atmospheric boundary layer (ABL) is analysed during a field experiment in Anqing, China (30∘37′ N, 116∘58′ E). Persistent GWs with periods ranging from 10 to 30 min over 10 h in the ABL within a 2 km height are detected by a coherent Doppler lidar from 4 to 5 September 2018. The amplitudes of the vertical wind due to these GWs are approximately 0.15–0.2 m s−1. The lifetimes of these GWs are longer than 20 wave cycles. There is no apparent phase progression with altitude. The vertical and zonal perturbations in the GWs are 90∘ out of phase, with vertical perturbations generally leading to zonal ones. Based on experiments and simplified two-dimensional computational fluid dynamics (CFD) numerical simulations, a reasonable generation mechanism of this persistent wave is proposed. A westerly low-level jet of ∼5 m s−1 exists at an altitude of 1–2 km in the ABL. The wind shear around the low-level jet leads to wave generation under the condition of light horizontal wind. Furthermore, a combination of thermal and Doppler ducts occurs in the ABL. Thus, the ducted wave motions are trapped in the ABL and have long lifetimes.

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