WORLD METEOROLOGICAL ORGANIZATION INSTRUMENTS AND OBSERVING METHODS R E P O R T No. 71 Instrument Development Inquiry (Sixth Edition) by J.P. van der Meulen Netherlands WMO/TD No. 878 1998 NOTE The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of the World Meteorological Organization concerning the legal status of any country, territory, city or area, or its authorities, or concerning the limitation of the frontiers or boundaries. This report has been produced without editorial revision by the Secretariat. It is not an official WMO publication and its distribution in this form does not imply endorsement by the Organization of the ideas expressed FOREWORD The provision of compatible measurements of high quality is fundamental for the operational and research programmes of Members of the World Meteorological Organization. Therefore, the development and use of new technology for effective and economical acquisition of data and, in particular, for the automation of observations is considered to be of great importance. The Twelfth Congress of WMO urged that Members continue and, to the extent possible, increase their programmes for the development of new data acquisition systems, sensors and instruments, including those for monitoring the composition of the atmosphere. This is often now done in close collaboration with instrument manufacturers and designers in the private sector. WMO, and particularly the Commission for Instruments and Methods of Observation (CIMO), has for a long time been publishing information 0fl new developments in instrumentation and data acquisition systems. Since 1968 five editions of publication with the title of "Instruments Development lnquiry" have been published. This, the sixth edition of the Instrument Development Inquiry, contains the information from a comprehensive survey of the state-of-the-art in development of meteorological instruments and of the new Instruments introduced into service during the last four years. The information was provided by 27 Members in 208 completed questionnaires. This demonstrates a significantly growing interest and participation compared with the fifth edition. The information in this publication will assist Members in selecting equipment for use in new applications or as replacement for obsolete instrumentation. Availability of this publication to instrument manufacturers may also be useful in decisions regarding development programmes. I wish to thank Dr. J.P. van d& Meulen, the CIMO Rapporteur on Instrument Development, who has again prepared this excellent report and the Royal Netherlands Meteorological Institute for its support of this undertaking. My thanks go also to all those who contributed the information by means of the completed questionnaires. (Dr. J. Kruus) President of the Commission for Instruments and Methods of Observation iv Contents 0. Summary .......................................................................... 1 1. Introduction ........................................................................ 3 1. Background ..................................................................... 3 2. Organization ..................................................................... 3 3. Response ........................................................................ 4 4. Items for classification ............................................................. 5 5. Motivation ...................................................................... 6 2. Analysis ........................................................................... 7 1. Introduction ..................................................................... 7 2. Results ......................................................................... 7 3. General conclusions ............................................................... 12 3. Information per entry in detail .......................................................... 13 1. Instruments under development ...................................................... 14 1.1. Measurement of Meteorological Variables .................................... 14 1.1.1. General .............................................................. 14 1.1.2. Measurement of temperature ............................................. 14 1.1.3. Measurement of atmospheric pressure ...................................... 24 1.1.4. Measurement of humidity ................................................ 27 1.1.5. Measurement of surface wind ............................................. 32 1.1.6. Measurement of precipitation ............................................. 44 1.1.7. Measurement of radiation ................................................ 48 1.1.8. Measurement of sunshine duration ......................................... 57 1.1.9. Measurement of visibility ................................................ 58 1.1.10. Measurement of evaporation ............................................. 59 1.1.11. Measurement of soil moisture ............................................ 60 1.1.12. Measurement of upper air pressure, temperature, humidity ..................... 61 1.1.13. Measurement of upper wind ............................................. 65 1.1.14. present and past weather, state of the ground: ............................... 66 1.1.15. Observation of clouds .................................................. 68 1.2. Observing Systems ....................................................... 70 1.2.1. Measurement at automatic meteorological stations ............................ 70 1.2.2. Instruments and observations at aeronautical stations .......................... 74 1.2.3. Aircraft observations .................................................... 75 1.2.4. Marine observations .................................................... 77 1.2.5. Special profiling techniques for the boundary layer and the troposphere ............ 79 1.2.6. Rocket measurements in the stratosphere and mesosphere ....................... 80 1.2.7. Locating the sources of atmospherics ....................................... 80 1.3. Other ................................................................. 81 2. Instruments put into operational use ................................................... 87 2.1. Measurement of Meteorological Variables .................................... 87 2.1.1. General .............................................................. 87 2.1.2. Measurement of temperature ............................................. 90 2.1.3. Measurement of atmospheric pressure ..................................... 123 2.1.4. Measurement of humidity ............................................... 128 2.1.5. Measurement of surface wind ............................................ 129 2.1.6. Measurement of precipitation ............................................ 146 v 2.1.7. Measurement of radiation ............................................... 157 2.1.8. Measurement of sunshine duration ........................................ 168 2.1.9. Measurement of visibility ............................................... 169 2.1.10. Measurement evaporation .............................................. 180 2.1.11. Measurement of soil moisture ........................................... 181 2.1.12. Measurement of upper air pressure, temperature, humidity .................... 181 2.1.13. upper wind ......................................................... 188 2.1.14. present and past weather, state of the ground ............................... 193 2.1.15. Observation of clouds ................................................. 195 2.2. Observing Systems ...................................................... 202 2.2.1. Measurement at automatic meteorological stationss ........................... 202 2.2.2. Instruments and observations at aeronautical stations ......................... 224 2.2.3. Aircraft observations ................................................... 227 2.2.4. Marine observations ................................................... 229 2.2.5. Special profiling techniques for the boundary layer and the troposphere ........... 232 2.2.6. Rocket measurements in the stratosphere and mesosphere ...................... 236 2.2.7. Locating the sources of atmospherics ...................................... 236 2.3. Other ................................................................ 237 Appendix A: Questionnaire .............................................................. 247 vi 0. Summary This publication reports on the results of the sixth edition of the Instrument Development Inquiry. The CIMO Working Group on Surface Measurements had decided to circulate to all W.M.O. Members a new questionnaire on instrument development. This inquiry is in line with resolution 4 (Cg-XII) and CIMO-XI recommendations. A total number 208 completed questionnaires from 27 countries were returned. Responses from 15 countries informing that no developments were carried out were recieved as well. In this questionnaire a choice could be made between: (1) Instrument under development, and (2) Instrument put into operational use in recent 4 years The questionnaire also asked to indicate the category-of-measurement number to which the (to be) developed instrument belongs. Twenty-three possibilities were put on the List of Categories (like Measurement of atmospheric pressure, or temperature, etc.). This list is based on the newest, sixth version of the Guide to Meteorological Instruments