Weather Radar Networking, Softcover reprint of the original 1st ed. 1992
COST 73 Project / Final Report

Over the past twenty years, there has been a rapid expansion in the number of opera­ tional, digital weather radars in Europe. Work within COST 73 stimulated the use of data from these radars and also demonstrated the potential of the international exchange of weather radar data in near real-time. The Management Committee of the COST 73 Project have laid the foun­ dations upon which future international operational radar networking may be built in Europe, and has indicated the directions that future weather radar technological developments might take. Throughout this five year Project, it has been possible to achieve success o~ through the goodwill of the participants. The considerable international co-operation is, in no smaIl measure, the underpinning reason why the Management Committee of COST 73 have been able to address such a wide range of topics within the general category of international weather radar networking. It has been an honour to have had the opportunity to act as Chairman of a group of meteorolo­ gists, engineers and managers possessing such a wide variety of talents and experience. I would like to take this opportunity to thank them all for their many and varied contributions.

1.0 Introduction.- 2.0 Summary and Recommendations.- A. Summary.- B. Recommendations.- Operational networking continuity.- Guidelines for the exchange of radar products.- Data transmission.- Network structure.- North Sea radar coverage.- Electronically scanning radar project.- Follow-on COST project.- Multi-national hydrological applications.- Training.- Wet deposition of pollution.- Radar systems database.- 3.0 Organisation of Work in the Project.- The form and role of the Management Committee.- Financing of the Project.- Support of the CEC.- Project Co-ordinator.- Report structure and working groups.- Total estimated cost of the COST 73 Project.- Seminars.- 4.0 Study Results from the Project.- Radar networking in Europe.- Current distribution and types of radar.- Operational radar characteristics.- Conventional radars.- Doppler radars.- Techniques.- Waveforms.- MTI performance.- Transmitter/receiver principles.- A typical modern Doppler radar.- Benefits of Doppler radar.- Identifying ground echoes.- Wind measurements.- Manual interpretation techniques.- Automatic interpretation techniques.- System outputs and usefulness.- Meteorological aspects.- Practical aspects.- Radar data generation and analyses used in different countries - obtained from the results of a questionnaire.- A proposal for a radar meteorology training curriculum.- Types of users requiring training.- Meteorologists/scientists.- Technicians/engineers.- Scientific assistants.- Computer specialists.- Specialist users.- Training curriculum.- Radar site processing.- Current radar site processing characteristics.- Occultation.- Useful range of weather radars.- Theoretical range of radars.- Effective earth radius for radar and optical propagation.- Practical determination of the lowest usable beam axis.- Theodolite measurements.- Use of a geographical map or geographical data base.- Format for COST purposes.- Coverage map and database.- Weather radar measurements, derived quantities and units employed.- Results of weather radar measurements.- Echo intensity.- Echo position and height.- Assignment of intensity class intervals in digital reflectivity processing.- Conventional radar products.- Doppler radar products.- Summary.- Clutter cancellation.- Basic considerations.- Relevance of clutter elimination.- Choice of wavelength.- Choosing a radar site.- Clutter characteristics.- Cross section of clutter and weather targets.- Variability of clutter and anaprop.- Clutter removal in real-time.- Clutter avoidance.- Pre-processing of the radar signal.- Distribution of clutter in space.- Continuity of weather echoes in time.- Use of other meteorological data.- Clutter map.- Additional image processing.- Sampling requirements and radar scan constraints.- Clutter elimination.- Quantitative applications.- A possible solution.- Summary.- Calibration of radar equipment and adjustment of radar data.- Hardware calibration of radar systems.- Meteorological adjustment of radar data.- Software structure.- Control of the radar.- Correction of data.- Products to be produced by the site system.- Products, transmission and receipt.- Typical system sizes.- Low-cost display systems.- Potential users of low-cost display systems.- The uses of low-cost display systems.- Low-cost display requirements.- The use of PCs.- Storage requirements.- Operational considerations.- Screen layout.- Data reception.- Menu-driven interface.- Main menu.- Controlling the replay sequence.- On-line help system.- Colours.- Replay options.- Record interval.- Coastline/boundary on/off.- Save preferences.- Select image.- Technical characteristics of some of the commercially available video boards.- End user requirements and applications of weather radar data.- End user requirements.- Weather radars and computer systems.- Transmission systems.- End users’ workstation.- Applications of weather radar data.- Weather radar for winter operations.- Weather radar in road maintenance.- Weather radar for agricultural applications.- Other uses of the COST image and other weather radar data.- Weather radar measurements for research purposes.- Data transmission.- Codes.- The Global Telecommunication System.- Structure of the World Meteorological Organization Global Telecommunication System (GTS).- Transmission of COST 73 images on the WMO GTS in ITA-5 code.- Headeres and trailers.- The Co-operative Olympus data experiment.- Results of trials and other experiences in radar data transmission.- Compression of radar images.- Run length encoding(RLE).- Huffman compression.- Lempel-Ziv-Welch (LZW) algorithm.- Software for coding and decoding radar images in FM 94 BUFR.- Radar network centres.- Software structures.- Functions of the data network.- Functions of the central network system.- Communications.- Product processing.- Database and archiving.- Possible hardware and software.- Merging data from multiple radars.- Products.- Severe weather algorithms for use with radar reflectivity data.- Multi-national weather radar data compositing.- User requirements for multi-national composites.- Forecasting the weather.- Pollutant monitoring and wet deposition.- Scientific understanding and research.- International river watch.- Commercial services.- Bilateral and multi-national agreements.- Elements of multi-national products.- Past experience.- New COST 73 products.- Implementation.- Real-time trials.- Assessment of the use of the COST 73 image for maritime forecasting in the southern North Sea.- A proposal for weather radars to be located in the North Sea.- Preliminary information about both project proposals.- Proposed plan of action.- Proposed project schedule.- The way ahead.- Development of national radar networks.- Advanced radars.- Electronically scanning radar antenna.- Basic principles.- Applications.- Frequency control.- Phase control.- Potential applications - COST 73 considerations.- Summary.- International exchange of radar data.- International co-ordination and funding.- Development of applications for the benefit of the economy of Europe.- 5.0 Recommendations.- Operational networking continuity.- Guidelines for the exchange of radar products.- Data transmission.- Network structure.- North Sea radar coverage.- Electronically scanning radar project.- Follow-on COST project.- Multi-national hydrological applications.- Training.- Wet deposition of pollution.- Radar systems database.- Acknowledgements.- 6.0 References.- 7.0 Annexes.- 1: Memorandum of Understanding.- 2: Meetings and Membership of the Management Committee.- 3: List of COST papers and Working Documents.- 4: Glossary of terms related to radar and satellite data.- 5: Specification of FM-94 BUFR.- 6: Proposals for additional multi-national radar based products.- 7: Proposed new COST Project on advanced radar systems.- 8: Severe weather definitions and useful algorithms.- 9: Advanced radars: current measurement capability.