AMOSSG/3-SN No. 4

4/1/02

AERODROME METEOROLOGICAL OBSERVING SYSTEMS STUDY GROUP (AMOSSG)

THIRD MEETING

Miami, 22 to 25 January 2002

Agenda Item	7:	Development of guidance material on automatic weather observing systems

(Presented by the Secretary)

SUMMARY
The group should reconfirm the principles for the development of guidance material on automatic weather observing systems agreed at the AMOSSG/2 Meeting.

1.	INTRODUCTION

1.1	The group will recall that the need for guidance material was addressed by the AMOSSG/1 and AMOSSG/2 Meetings and that an initial proposal developed by the Secretary was considered at the second meeting.

2.	BACKGROUND

2.1	It may be recalled that the group was of the opinion that there was a need for guidance related to the use of automated observing systems. However, the group realized that it would not be appropriate to include lengthy and detailed descriptions of automated weather observing systems in ICAO regulatory documents like Annex 3 — Meteorological Service for International Air Navigation. Therefore, the development of guidance material would seem to be the best solution.

2.2	Furthermore, the group agreed at its second meeting that, in view of the fairly wide scope of the subject, the optimum solution would be the development of a new, stand-alone Manual on Automated Weather Observing Systems at Aerodromes rather than the inclusion of guidance in existing ICAO documents.

2.3	With regard to the time schedule to be followed, the group concluded that it would not be realistic to develop a draft Manual before the proposed MET Divisional Meeting (2002) is convened due to two main reasons:

a)	procedural reasons. The corresponding Standards and Recommended Practices (SARPs) would only be developed as part of Amendment 73 to Annex 3 for consideration by the MET Divisional Meeting (2002); and

b)	practical reasons. The development of such a manual would be a major undertaking and active and prolonged participation by the members and advisors of the AMOSSG would be required.

In view of this, the group agreed that the development of a manual on automated weather observing systems should be proposed to the MET Divisional Meeting (2002).

2.4	The group will recall that a draft outline of the content of the proposed Manual on Automated Weather Observing Systems at Aerodromes was reviewed by the group. It was agreed that, for initial planning purposes, the new manual would follow the structure of the structure of the second edition of the Manual of Runway Visual Range Observing and Reporting Practices (Doc 9328) and would consist of the following chapters:

Introduction

Definitions and explanation of terms

Automatic observations of

surface wind

visibility

RVR

present weather

cloud

temperature and dew-point temperature

atmospheric pressure

supplementary information

Integrated automated observing systems

Reporting practices

2.5	The group noted that the outline was of a preliminary nature and that it did not include any details. It was suggested that issues such as maintenance and back-up procedures should be well covered in the new manual under "Integrated automated observing systems". Also the importance of using common data processing for all the displays of meteorological information no matter whether they were located at the meteorological station or at an ATS unit should be highlighted. The importance of close coordination with WMO in developing the manual was emphasized.

3.	ACTION BY THE GROUP

3.1	The group is invited to:

a)	note the information provided in this study note;

b)	reconfirm the course of action proposed at the AMOSSG/2 Meeting; and

c)	agree that a proposal for the development of a new Manual on Automated Weather Observing Systems at Aerodromes be tabled for consideration by the upcoming MET Divisional Meeting (2002).

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