• Chan, P. W., 2010: Lidar-based turbulence intensity calculation using glide-path scans of the Doppler light detection and ranging (lidar) systems at the Hong Kong International Airport and comparison with flight data and a turbulence alerting system. Meteor. Z., 19, 549563.

    • Search Google Scholar
    • Export Citation
  • Chan, P. W., and Shao A. M. , 2007: Depiction of complex airflow near Hong Kong International Airport using a Doppler lidar with a two-dimensional wind retrieval technique. Meteor. Z., 16, 491504.

    • Search Google Scholar
    • Export Citation
  • Chan, P. W., and Lee Y. F. , 2012: Application of short-range lidar in wind shear alerting. J. Atmos. Oceanic Technol., 29, 207220.

  • Chan, P. W., Shun C. M. , and Wu K. C. , 2006: Operational lidar-based system for automatic windshear alerting at the Hong Kong International Airport. Preprints, 12th Conf. on Aviation, Range, and Aerospace Meteorology, Atlanta, GA, Amer. Meteor. Soc., 6.11. [Available online at https://ams.confex.com/ams/Annual2006/techprogram/paper_100601.htm.]

  • Farazmand, M., and Haller G. , 2012: Erratum and addendum to “A variational theory of hyperbolic Lagrangian coherent structures” [Physica D 240 (2011) 574–598]. Physica D, 241, 439441.

    • Search Google Scholar
    • Export Citation
  • Fawcett, T., 2006: An introduction to ROC analysis. Pattern Recognit. Lett., 27, 861874.

  • Fujita, T. T., 1978: Manual of downburst identification for Project NIMROD. SMRP Research Paper 156, University of Chicago, 104 pp.

  • Haller, G., 2001: Distinguished material surfaces and coherent structures in three-dimensional fluid flows. Physica D, 149, 248277.

  • Haller, G., 2011: A variational theory of hyperbolic Lagrangian coherent structures. Physica D, 240, 574598.

  • Haller, G., and Beron-Vera F. J. , 2012: Geodesic theory of transport barriers in two-dimensional flows. Physica D, 241, 16801702.

  • Haynes, A., 1980: Description of a program developed for the analysis of windshears experienced during aircraft approach to landing. Royal Aircraft Establishment Tech. Memo. FS 321, 25 pp.

  • ICAO, 2005: Manual on low-level windshear and turbulence. Doc 9817, AN/449, 1st ed. International Civil Aviation Organization, 222 pp.

  • Jones, J. G., and Haynes A. , 1984: A peak-spotter program applied to the analysis of increments in turbulence velocity. Royal Aircraft Establishment Tech. Rep. 84071, 76 pp.

  • Ottino, J. M., 1997: The Kinematics of Mixing: Stretching, Chaos, and Transport. Cambridge University Press, 364 pp.

  • Peacock, T., and Dabiri J. , 2010: Introduction to focus issue: Lagrangian coherent structures. Chaos, 20, 017501, doi:10.1063/1.3278173.

    • Search Google Scholar
    • Export Citation
  • Proctor, F. H., Hinton D. A. , and Bowles R. L. , 2000: A windshear hazard index. Preprints, Ninth Conf. on Aviation, Range, and Aerospace Meteorology, Orlando, FL, Amer. Meteor. Soc., 7.7. [Available online at https://ams.confex.com/ams/Sept2000/techprogram/paper_16347.htm.]

  • Shun, C. M., and Lau S. Y. , 2002: Implementation of a Doppler light detection and ranging (lidar) system for the Hong Kong International Airport. Preprints, 10th Conf. on Aviation, Range, and Aerospace Meteorology, Portland, OR, Amer. Meteor. Soc., 8.3. [Available online at https://ams.confex.com/ams/13ac10av/techprogram/paper_39018.htm.]

  • Shun, C. M., and Chan P. W. , 2008: Applications of an infrared Doppler lidar in detection of wind shear. J. Atmos. Oceanic Technol.,25, 637–655.

  • Tang, W., Chan P. W. , and Haller G. , 2010: Accurate extraction of Lagrangian coherent structures over finite domains with application to flight data analysis over Hong Kong International Airport. Chaos,20, 017502, doi:10.1063/1.3276061.

    • Search Google Scholar
    • Export Citation
  • Tang, W., Chan P. W. , and Haller G. , 2011a: Lagrangian coherent structure analysis of terminal winds detected by lidar. Part I: Turbulence structures. J. Appl. Meteor. Climatol., 50, 325338.

    • Search Google Scholar
    • Export Citation
  • Tang, W., Chan P. W. , and Haller G. , 2011b: Lagrangian coherent structure analysis of terminal winds detected by lidar. Part II: Structure evolution and comparison with flight data. J. Appl. Meteor. Climatol., 50, 21672183.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 8 8 8
PDF Downloads 5 5 5

Lagrangian Detection of Wind Shear for Landing Aircraft

View More View Less
  • 1 Department of Mechanical Engineering, McGill University, Montreal, Quebec, Canada
  • | 2 Hong Kong Observatory, Kowloon, Hong Kong, China
  • | 3 Department of Mechanical Engineering, McGill University, Montreal, Quebec, Canada, and Institute for Mechanical Systems, ETH Zurich, Zurich, Switzerland
Restricted access

Abstract

Recent studies have shown that aerial disturbances affecting landing aircraft have a coherent signature in the Lagrangian aerial particle dynamics inferred from ground-based lidar scans. Specifically, attracting Lagrangian coherent structures (LCSs) mark the intersection of localized material upwelling within the cone of the lidar scan. This study tests the detection power of LCSs on historical landing data and corresponding pilot reports of disturbances from Hong Kong International Airport. The results show that a specific LCS indicator, the gradient of the finite-time Lyapunov exponent (FTLE) field along the landing path, is a highly efficient marker of turbulent upwellings. In particular, in the spring season, projected FTLE gradients closely approach the efficiency of the wind shear alert system currently in operation at the airport, even though the latter system relies on multiple sources of data beyond those used in this study. This shows significant potential for the operational use of FTLE gradients in the real-time detection of aerial disturbances over airports.

Corresponding author address: George Haller, Institute of Mechanical Systems, ETH Zurich, Tannenstrasse 3, CLA J.27, 8044 Zurich, Switzerland. E-mail: georgehaller@ethz.ch

Abstract

Recent studies have shown that aerial disturbances affecting landing aircraft have a coherent signature in the Lagrangian aerial particle dynamics inferred from ground-based lidar scans. Specifically, attracting Lagrangian coherent structures (LCSs) mark the intersection of localized material upwelling within the cone of the lidar scan. This study tests the detection power of LCSs on historical landing data and corresponding pilot reports of disturbances from Hong Kong International Airport. The results show that a specific LCS indicator, the gradient of the finite-time Lyapunov exponent (FTLE) field along the landing path, is a highly efficient marker of turbulent upwellings. In particular, in the spring season, projected FTLE gradients closely approach the efficiency of the wind shear alert system currently in operation at the airport, even though the latter system relies on multiple sources of data beyond those used in this study. This shows significant potential for the operational use of FTLE gradients in the real-time detection of aerial disturbances over airports.

Corresponding author address: George Haller, Institute of Mechanical Systems, ETH Zurich, Tannenstrasse 3, CLA J.27, 8044 Zurich, Switzerland. E-mail: georgehaller@ethz.ch
Save