Experience of the Japan Meteorological Agency with the Operation of Wind Profilers Instrument and Observing Methods Report No. 110 This publication is available in pdf format, at the following link: http://www.wmo.int/pages/prog/www/IMOP/publications-IOM-series.html © World Meteorological Organization, 2012 The right of publication in print, electronic and any other form and in any language is reserved by WMO. Short extracts from WMO publications may be reproduced without authorization, provided that the complete source is clearly indicated. Editorial correspondence and requests to publish, reproduce or translate this publication in part or in whole should be addressed to: Chairperson, Publications Board World Meteorological Organization (WMO) 7 bis, avenue de la Paix Tel.: +41 (0) 22 730 8403 P.O. 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TABLE OF CONTENTS TABLE OF CONTENTS ........................................................................................... iii FOREWORD ......................................................................................................... v SUMMARY ..........................................................................................................vii 1 INTRODUCTION.............................................................................................. 1 2 DEVELOPMENT OF WIND PROFILER SYSTEM IN JAPAN ......................................... 1 2.1 Background and Purpose ..................................................................... 1 2.2 Requirements for Installation of Wind Profilers ................................... 1 2.2.1 Site Location .................................................................................. 1 2.2.2 Radio Frequency ............................................................................ 3 2.2.3 Height and Time Resolution............................................................ 3 2.2.4 Others............................................................................................ 3 3 OBSERVATION CHARACTERISTICS AND PERFORMANCE...................................... 4 3.1 Principle of Observation....................................................................... 4 3.2 Observation Parameters ...................................................................... 5 3.3 Observation Performance .................................................................... 9 3.3.1 Height Coverage............................................................................. 9 3.3.2 Data Acquisition Rate..................................................................... 9 3.4 Valuation of Observation Precision .................................................... 10 3.4.1 Comparison with Radiosondes...................................................... 10 3.4.2 Comparison with Numerical Weather Prediction ........................... 11 4 INFRASTRUCTURE AND HARDWARE ........................................................................ 12 4.1 Overview and Features of the System .............................................. 12 4.1.1 Constituents Parts of an Observatory ........................................... 14 4.1.2 Constituents Parts of the Control Center ...................................... 15 4.2 Inspection and Maintenance of Equipment......................................... 16 4.3 Operation Rate and Failure-related Shutdown Ratio........................... 16 5. QUALITY MANAGEMENT .............................................................................. 20 5.1 Overview of Quality Management ...................................................... 20 5.2 Quality Management at Observation Stations..................................... 21 5.2.1 Removal of ground clutter............................................................ 21 5.2.1.1 Hardware Measures................................................................. 21 5.2.1.2 Software Measures.................................................................. 21 5.2.2 Spectrum width check .................................................................. 23 5.2.3 Homogeneity check in the wind field ............................................ 23 5.2.4 Consensus average ...................................................................... 25 - iii - 5.2.5 Removal of echo from migratory birds.......................................... 26 5.2.5.1 Introduction of a function to separate bird echo from received signals leaving only atmospheric echo .................................................... 26 5.2.5.2 Introduction of all-weather automatic operation system ......... 28 5.3 Quality Management at Control Center............................................... 31 5.3.1 Quadric surface approximation check........................................... 31 5.3.2 Vertical shear check ..................................................................... 33 5.3.3 Manual quality management ........................................................ 34 5.3.4 Quality management status at Control Center .............................. 35 6. USE OF OBSERVATION DATA ....................................................................... 36 6.1 Distribution of Observation Data........................................................ 36 6.2 Use of Data in NWP system................................................................ 36 6.3 Examples of Analysis ......................................................................... 36 6.3.1 Troughs and Ridges...................................................................... 36 6.3.2 Deformation of Cold Fronts .......................................................... 37 6.3.3 Detection of Precipitation............................................................. 38 6.3.4 Distinguishing between Rain and Snow ........................................ 39 6.3.5 Estimation of Cloud Layers ........................................................... 39 6.3.6 Turbulence................................................................................... 40 REFERENCES ..................................................................................................... 41 - iv - FOREWORD This publication discusses the Japanese Meteorological Agency’s (JMA) operational experience with Doppler mode radar wind profilers in Japan, to provide guidance to other WMO Members planning to implement wind profiler networks. The report discusses the considerations to be taken into account when initially installing a wind profiler at a new site, and the different factors to be taken into account in selecting the appropriate wind profiler for the desired purpose. The report goes into the principles of wind profiler operation, describes the performance to be expected under varying atmospheric and environmental conditions, and compares wind profiler data with that from radiosondes and numerical weather assimilation analyses. Importantly, the report discusses the quality management procedures to be carried out to ensure data of optimum quality, and ends by illustrating the use of the data in support of service provision. As the first of this kind of report which is dedicated to the operational use of radar wind profilers, I am sure it will be a valuable source of information for those venturing into the operational use of wind profilers, and I wish to express my sincere gratitude and that of the Commission for Instruments and Methods of Observation (CIMO) to its authors from the Japanese Meteorological Agency, for this valuable contribution to the CIMO literature. I also wish to thank the CIMO experts who gave their time to review an earlier draft of the report. (Prof. B. Calpini) President Commission for Instruments and Methods of Observation - v - - vi - SUMMARY A wind profiler is a device that continually measures wind speed and direction in the upper air using radio waves. It plays an important role in monitoring atmospheric phenomena and providing initial values for numerical prediction models. Operational wind profiler networks are used around the world, including in the United States, Europe, and Japan. They have worked to improve the corresponding data quality management and advance the technologies that use this data. First, this guidance focuses on the matters which should be considered (such as site location, radio frequency, and height and time resolution) on a new installation of wind profilers, based on the operational experience of the wind profiler network in Japan (hereinafter referred to as “WINDAS”). Japan Meteorological Agency introduced wind profilers in the 1.3 GHz band, after considering required height coverage, radio frequency allocation, and costs. Since the administration policy of radio frequency allocations could differ by countries, especially