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About 88% of stations report some BUFR, about 78% report native BUFR with roughly 10% reporting reformatted TEMP (see below). (In 2023 a problem was noted with BUFR reports from about 12 Indian stations and 8 Malaysian stations: the winds are in the wrong units! In BUFR winds should always be in m/s.) The proportion of native high-resolution reports is growing in fits and starts, recently in the USA (2017), Japan (July 2018), Chile+Argentia (2018), Brazil (2019 - incomplete) and some Russian stations (late 2018/2019) - this pushed the % with native reports over 50% in the second quarter of 2019. In October 2019 most Chinese stations started providing low-resolution native BUFR reports and most Chinese TAC radiosonde reports stopped in mid-January 2020. In 2021 the resolution at Chinese stations improved to about 200 levels at a few stations, then all Chinese stations at the start of June. A few Indian stations started providing high-resolution reports in 2020, but this has been erratic. In 2022 there have been a few more high-resolution reports from the USA and Caribbean and in Q2 2023 most Canadian stations started reporting high-resolution data, but Mexico regressed to TAC because of a Cyber attack. A small proportion of BUFR reports are incomplete (eg data above 100 hPa missing). Reports from the ASAP ships are now only available in BUFR format (most ASAPs changed identifier in late 2017). As of late 2019 stations in Finland, Norway, Sweden and France no longer provide alphanumeric reports, plus scattered stations elsewhere. About 10 European countries are now sending radiosonde descent data in BUFR (not shown). There was a dearth of radiosonde reports from West Africa in late-April/May 2019 but this recovered somewhat by June 2019. In early 2025 there was a reduction in reports (especially BUFR) from msothern Africa due to a cyber attack.
In 2018 there were some high-resolution dropsonde reports on the GTS and there were more in 2019 and ECMWF started assimilating them on 4 September 2019 (NB dropsonde reports are intermittent). ECMWF is monitoring descent data from various radiosonde stations, mainly in Europe and started assimilating German descent profiles in July 2020 and RS41 descent data from ships in 2021.
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