Doc 3.1.3 - Review of algorithms used in AWOS/AWS and proposal for their standardization by B. Hartley
HMEI was asked what were the results of its investigation into publication of algorithms for AWS. The previous meeting of this group had requested the HMEI Secretariat to look into this issue with its membership.

The HMEI Secretariat was able to reply that:

• Generally its members had informed HMEI that algorithms, that were public knowledge (i.e. formulae in the CIMO Guide), were referred to or published in the product specification or manual.
• More confidential information, researched and produced by the manufacturer, was sometimes kept confidential, depending on the individual company policy. 
• However  it was noted that the buyer of a product was often in the position to ask for information about algorithms directly from their manufacturer. 
• The HMEI Member manufactures present expressed their companies willingness in most instances to cooperate with their customers.
• The meeting Vice -Chairman, Stefen Waas, agreed that in his dealings with manufacturers as the buyer/user, manufacturers usually willing to be very cooperative in this matter.

To Summarize
Many manufactures are completely open with algorithms and publish them freely. Others may need to be approached, at the time of buying an instrument or system, to assess how much information they are prepared to divulge and under what conditions.

Recommendations

• Publish all the standard formulae as an annex to the CIMO Guide, supported by input from HMEI.
• The section on radiation was deemed to need updating, and it was recommended that this updated request be passed to the ET on Radiation for their action.
• Quality control checks are also recommended to be expanded in the WMO Guide to Meteorological Instruments and Methods of Observation (CIMO Guide). These do exist in volume iii of the guide, and need to be more generally made known.
• Two sensitive areas need further research and development, namely measurement of solid precipitation, especially near 0 degrees, and present weather.
• The meeting decided to request a questionnaire to WMO Members asking them what algorithms them use in their service. The aim is to define a standard set of algorithms that will be recommended by WMO.
  

• The principles expressed in the paper are good, but the implementation is considered to be very difficult, and getting manufacturers to work together on this issue will be a challenge. The use of wireless sensors was suggested, but interference issues would need to be considered.
• The CMA development of an interoperable AWS was presented.
• The development of interoperable protocols is considered a worthwhile activity, but it would take several years of works. The advantages are considerable. It would require contacting groups who are involved in this type of work. The industry would benefit by being able to work together with a common protocol. The interoperability of sensors from various manufacturers would be much simpler if such a standard protocol at the applications level could be developed.
• It may be possible for the industry to work together on development of a common protocol. One suggestion was that a team from the industry may be able to be formed to work on this issue.

Doc 3.2(1) Development of guidelines and procedures for the transition from manual to Automatic Weather Stations by Mike Molyneux
This document presented an outline on guidelines and procedures for the transition from manual to automatic weather stations. The meeting discussion provided additional information on such issues as site security, overlap period, long-term costs, etc.

Results

• The document will be expanded with assistance from the Expert Team to form a comprehensive document providing detailed information on how to translate from a manned site to an automated site.
• It was also decided that the ET should  work closely with ET-AWS

Doc 3.2(2)  Instrument Development Inquiry by Jitze van der Muelen
The Instrument Development Inquiry is is created from a questionnaire sent out every 4 years to find out about new instrument developments. It lists instruments that have recently become operational, and also instruments that are under development. It was suggested to make a WMO webpage for this inquiry, to be updated every 12 months.

Item 3.3 Surface measurements in extreme weather conditions

Doc 3.3(1)Requirements for instruments on meteorological icing by A. Heimo
This report presented the results from the COST 727 Action on atmospheric icing. Prior to this COST action, there were no good ice detectors, CIMO guidelines were limited and modelling of ice was almost non-existent. COST 27 has 13 countries worldwide participating in this work in two Working Groups (WG), WG1 to develop scientific understanding of icing processes, and WG2 is to compile icing data and to harmonize ongoing measurements and to assist in the development of robust ice measurement techniques and instruments.

Two instruments are currently recommended for ice measuring; Goodrich (Rosemount) instrument and the Swedish Combitech Icemonitor for measuring the weight of ice. Campbell Scientific Canada is now the Goodrich distributor.

An instrument to measure 0.1 to 1.0 micron ice particles does not exist, but is needed. Calibration of instruments is being done in Japan using icing wind tunnel. There are now 6 test stations in Europe equipped with the Combitech instrument.

COST has also developed the European Icing Dataset. The measurement of the liquid water content and the droplet number concentration are required for the models, but there are currently no instruments that measure these parameters.

COST is still working on developing specifications for ice detectors and for testing. COST want to extent this action for another four year period, and are seeking support from CIMO for this continuation.

Doc 3.3(2) Surface measurements in extreme weather conditions by M Novitsky
Michael Novitsky from the Russian Federation talked about instrumentation that can cope with extreme climates. He gave specific examples of instruments from Vaisala, Gill and R.M. Young. He advised that there are still some problems with the communication electronics failing at extremely cold conditions. However the HMEI members present stated that this is generally not a problem, that electronics can be built to cover any temperature range, either extremely hot or extremely cold.

Comments

• Survivability of instruments after a severe weather event is an issue. However the cost of developing such instruments is very great and the market is small. Also the continuing measurement of standard parameters after a severe event is a requirement. The best way may be bring in portable equipment rather than make it a requirement that the equipment survives a major event. Also redundancy of equipment throughout an area would also assist when equipment fails during extreme events.
• The value of Intercomparisons to assist manufacturers to improve their manufacturing equipment was stressed.

• It was recommended that the CIMO Guide be updated with information on instrumentation for extreme weather events.

Item 4 Proposal for Update of the Guide to Meteorological Instruments and Methods of Observation (WMO-No. 8)

Doc 4.1 Proposal for update of the guide to meteorological instruments and methods of observation (WMO-No. 8) by Mr KarlHeinz Klapheck See this document here
A paper was presented on operational uncertainty requirements and instrument performance. This relates to the table in Annex B.1 of the WMO CIMO Guide, 7th Edition, which lists variables and their range, resolution, required uncertainty, time constant, output averaging time and achievable measurement uncertainty. It was noted that the listed values need to be changed with extreme care, as these values are used by meteorological services when defining their requirements for instruments. Some changes were made to the table with consensus of the meeting.
 

Item 5 Activities Related to CBS/OPAG-IOS ET-AWS

Doc 5.1 Requirements for a robust, low power, continuous communications platform for AWS by Dr Igor Zahumensky
Discussion presented on the requirements for a robust, low power, continuous communications platform for all AWS, suitable particularly for remote locations. The team reviewed this document that was prepared by ET-AWS, to check that any aspects were overlooked, or changes required to the requirements. Such a platform is becoming more important as a replacement at manual sites, at remote locations, etc. New communications techniques tend to limit standardization. HMEI welcomes this document, it will assist manufacturers know what WMO’s requirements are regarding AWS, and also lets Met Services know what sort of systems are available for their upgrades to their networks. The industry was invited to provide comments on this document that can then be reviewed by ET-AWS for the next iteration of these requirements. The current team made some small suggestions to add to the document.
Comments:
a) An Annex will be prepared for the report of this meeting, to allow the information discussed during the meeting to be shared and coordinated amongst all relevant groups. Comments from HMEI will include a statement on the importance of these requirements for the industry, and how regular updating would also assist the industry keep abreast of new and changing requirements within WMO.

Doc 5.2 Requirements for new sensors or the integration of sensors to overcome the deficiencies of AWS following the migration from manual observations by Dr Igor Zahumensky
This document discusses the requirements for new sensors for the integration of sensors, to overcome the deficiencies of automatic weather stations (AWS), following the migration from manual observations. The requirements for sensors can be stated in three interrelated categories:

1. Requirements relating to performance of measurement
2. Requirements relating to traceability of measurements
3. Requirements relating to operational reliability

Doc 5.4 Siting Classification of AWS by Michel Leroy
The classification is based on the current procedures implemented by Météo-France. The report presented the work done so far by Météo-France. It is proposed that this classification, should be presented for adoption by CIMO and CBS, and that it would eventually be recognized as a joint WMO-ISO standard.

There was discussion on various points and issues raised by the document and proposal. After the discussions, the ET members were invited to submit, to Michel Leroy, any additions that might be necessary as soon as possible in order that the document can be prepared for presentation to the next CIMO session.

Item 7 Any Other Business

Docs 7.1 and 7.2 WMO Integrated Global Observing Systems (WIGOS) - Implementation and Pilot Projects by WMO secretariat
The meeting was informed about WIGOS, the WMO Integrated Global Observing Systems, a system of systems to link all WMO observing systems and interface with external observing systems (like GCOS) into a composite system. There are four main objectives: improve management and governance; increase interoperability; address the needs of the atmosphere and collaborate with other international agencies. There are three integration levels: Instruments and methods of observations level; the WIS data level and the quality management; quality control and quality assurance level. The meeting was advised of the five WIGOS Pilot Projects to be developed by the WMO Technical Commissions.

Doc 7.3 Report on Calibration Requirements for Satellite Sensing and Surface Variables by Jitze van der Muelen
This report presented the requirements for AWS hosted sensors to contribute directly to the calibration and ground-truth of spaced-based observations. It was stated that it is a challenge to integrate remotely sensed observations with surface-based AWS measurements, but that doing so would benefit ground-truthing of remotely sensed (satellite and/or radar) data. However the satellite community state that there is no requirement for such calibration and validation, and therefore the meeting noted the document and decided to stop any further work on this topic.

COST 727: Atmospheric Icing on Structures Measurements and data collection on icing: State of the Art See document here
A new COST Action has been accepted – ES0702, "European Ground-based Observations of Essential Variables for Climate and Operational METeorology (EG-CLIMET)". HMEI has contacted COST, and HMEI will be involved in this action, particularly in Working Group 1, which is involved with instrumentation.

RESULTS AND WORK PLAN
The meeting resulted in a well considered and itemized Work Plan. This Work Plan has 10 items to cover 4 major tasks: 1. Standardization in instrumentation and observations; 2. Automatization of surface observations; 3. Surface measurements in extreme weather conditions; 4. Miscellaneous tasks. Details of the Work Plan will be available in the  WMO report of this meeting.

HMEI is involved with 4 of the 10 items in the Work Plan:

• Under Task 1, Item 1b, there will be a survey of manufacturers in regard to automatic measurement of clouds, present weather etc. Mrs Bloemink will format a survey that will then be distributed to HMEI Member manufactures.
• Under Task 1, Item 1d, the HMEI Secretariat will collaborate as a manufacturers' contact in regard to the development of standards for the interoperability of instruments' hardware and software.
• Under Task 2, Item 2b, HMEI will cooperate with the ET in seeking and looking at new surface technologies and techniques.
• Under Task 3, Item 3c, HMEI will cooperate with the ET in investigations into appropriate sensors for measurement of extreme values of wind and precipitation.

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