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Warning to data users: Two timestamps are included in each drifing buoy observation message. Each timestamp is preceded by its related time significance (BUFR element 0 08 021). It must be noted that, in template TM315009, the first timestamp is this of the last known position (value is 26). This of the observation (time significance = 25), also called "nominal reporting time" is in second position. Do not confuse both.
This map shows the data buoys (moored and drifting) that reported in FM18 and BUFR (75%), in FM18 only (2%) and in BUFR only (23%) on the 16th of May 2016 (according to data received at ECMWF). That means that 98% of buoy data are henceforth sent in BUFR. The buoys reporting in FM18 only were mainly Indian moored buoys (DEMS) and Japanese drifting buoys (RJTD). During the coming months, more and more data will be sent in BUFR only. It must be noted that most of the FM18 data should disappear from the GTS on the 1st of September 2016.
Drifting buoy BUFR data - Survey on October 12th, 2014
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