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Since 2008, Iridium Short Burst Data (SBD) has been more and more used for the transmission of drifting buoy data ashore. Several centres are processing the raw data in order to send them onto the GTS in FM18 BUOY. Out of them, some are transmitted in FM94 BUFR (never-validated WMO template), in parallel.
By mid-2015, processing centres started the sending of drifting buoy data onto the GTS in BUFR, according to template TM315009. A survey, carried out in August 2016, showed that the data of 99.5% of the drifting buoys were sent onto the GTS in BUFR with the right template. The migration should be considered as completed. The transmission of TAC data for drifting buoys should end on the 1st November 2016. end 2016 the migration from TAC to BUFR is considered about complete for drifting buoys.
GTS headers for drifting buoy in BUFR format data start with character string 'IOB'.
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