AMDAR data is currently transmitted on the WMO Global Transmission System (GTS) in both text (FM42, see Manual on Codes, Volume I.1 Alphanumeric Codes) and binary (FM94, see Manual on Codes, Volume I.2 Binary Codes) formats.
A new AMDAR BUFR template has recently been developed and approved as notified in the Amendments to the Manual on Codes by the fast-track, Implemented on 2 May 2012. and WMO recommends that AMDAR programmes follow procedures for the implementation or migration to this format.
Specific information and procedures for pre-processing of AMDAR data for transmission of on the GTS is available in the AMDAR Reference Manual in Appendix IV.
Vertical profiles of AMDAR data are derived as the aircraft is on ascent or descent and en-routed data is derived as the aircraft flies at cruise altitudes of around 35,000 feet (10,500 metres).
From the AMDAR Observing System, the following meteorological parameters are measured or derived:
Additional non-meteorological parameters that can be reported, measured or derived include:
AMDAR data is processed, compiled and transmitted by the Onboard AMDAR System according to the sampling algorithms and frequencies defined in the AMDAR Onboard Software standards.
A water vapour (humidity) measurement from the aircraft platform can also be derived through the deployment and avionics integration of a water vapour sensor. Currently there is a single laser-diode sensor that delivers the required data quality and performance for operational deployment, namely the Water Vapour Sensing System 2nd Generation, WVSS-II, which has been deployed operationally in the USA (around 100 aircraft by mid-2013 on UPS and Southwest Airlines). Plans are also in place to commence deployment of the sensor in Europe and Australia.
More detailed information is available from:
AMDAR Data Quality
For information on AMDAR data quality, see the section on Data Quality in the page on the AMDAR Observing System.
WMO maintains the Aircraft Observations Data Monitoring email list, which provides WMO Members with information on aircraft-based and AMDAR data quality monitoring. The forum is used for posting of monthly data quality monitoring reports and ad hoc discussion on data quality issues.
The forum is available to AMDAR Focal Points and GTS users and managers of aircraft-based observational data.
Members are added to the Google Group email list by the Secretariat upon application. AMDAR Focal Points are made members of this group.
The online Google Groups forum is available here, for those members that register their membership email address via a Google Account.
|© World Meteorological Organization, 7bis, avenue de la Paix, Case postale No. 2300, CH-1211 Geneva 2, Switzerland - Tel.: +41(0)22 730 81 11 - Fax: +41(0)22 730 81 81 Contact us|