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Almost 70% of stations report in BUFR, only about 10% report proper BUFR with almost 60% reporting reformatted TEMP (see "structure" page and plots below). Reports may be incomplete (eg data above 100 hPa missing). The numbers have recovered from a dip (affecting several countries) seen at ECMWF in mid-November (due partly to slightly non-standard BUFR reports).
On 11 November 2014 ECMWF started assimilating a subset of the high resolution reports (about 16 stations from Europe plus some ASAP ships). After 21 November some of the ASAPs (those starting ASDE and ASEU) stopped reporting in TEMP SHIP format, they are now only available in BUFR format. We understand that some NWP centres are not yet in a position to assimilate BUFR radiosonde data, although they are working on this.
(Grey: TAC reports but no BUFR, Purple: BUFR reports but no TAC, Red *: position error. Light/dark blue indicates low/high vertical resolution BUFR data. Black ring - ship report, or identifier error!)
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