Upper Air Measurements of Wind and Turbulence with Doppler LIDAR Systems on Airports: Challenges and Opportunities

In air traffic operations, weather is one of the major causes of flight delays and accidents. Among all the weather conditions for aircrafts, wind conditions require to be monitored with high spatial and temporal resolution sensors and at the relevant altitude and locations in order to reduce their impact on air traffic for improving safety and / or for optimizing ATM. LIDAR sensors remain confidential and few are used for operational purposes. This paper presents the intrinsic performances of LIDAR profilers in terms of data availability and accuracy as well as the products that can be provided. Several applications of such LIDAR technology are then presented like wind measurements thanks to several experiments performed on airports. The study shows the difference of surface wind speed and wind direction measured with conventional ground-based anemometers and upper air wind conditions at different altitudes provided by LIDAR profilers. As shown by Figure 1, the mean difference on 10 minutes averaged wind speed between 200m and 10m reaches 5m/s during a two months trial performed at Toulouse-Blagnac airport in France. For the wind direction, the mean difference is slightly higher but the standard deviation is much higher. Indeed, in some conditions, the surface wind direction can differ from 180° compared to the wind direction at 200m. A comparison of wind provided by LIDAR and retrieved with Mode-S EHS data will be able performed. The study will then present the capability to retrieve turbulence quantity from the LIDAR profiler as well as its potential use for improving wind forecasts at airport. As perspectives the paper proposes the potential benefits of using such atmospheric LIDAR sensors for optimizing air traffic like airport capacities and for improving air traffic safety. Figure 1: Time series of measurements of wind speed (top) and wind direction (bottom) of the LIDAR at 40m (red) and 200m (blue) and AWOS wind speed (black) during April and May 2014 at Toulouse airport [1] ICAO Navigation, M. S. (July 2007). Annex 3 to Convention of International Civil Aviation - Part I Core SARPs - Part II Appendices and Attachments. Sixteenth Edition [2] Technical Regulations, Basic Documents No. 2, Volume II – Meteorological Service for International Air Navigation, 2010 edition, WMO-No. 49 [3] Wieringa, J., Representativeness of Wind Observations at Airports, Royal Netherlands Meteorological Institute, Bulletin of the American Meteorological Society, Vol 61, No 9, September 1980 [4] Beeken, A., Neumann, T., FINO1-platform: Operation and Data Analysis of an Off-shore based LIDAR Device (16. July – 30. November 2009), Wilhelmshaven, [5] Boquet, R. Parmentier, J.P. Cariou, Analysis and Optimization of Pulsed Doppler Lidar in Complex Terrain, EWEC, 2009 [6] Jaynes, D., LIDAR Validation and Recommendations for Wind Resource Assessments, AWEA, 2009 [7] Ludovic P. Thobois , Wind Measurements with ground-based fiber-based wind Doppler LIDAR systems for aviation weather applications, 15th AIAA Aviation Technology, Integration, and Operations Conference, June 2015