Below are plots of SYNOP/BUOY/radiosonde BUFR coverage for September December 2018 - reports as decoded at ECMWF, some reports not in standard BUFR are not decoded. Daily coverage (updated automatically) is available from the Monitoring Maps
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Surface (SYNOP) coverage
About 86% 87% of stations now report in BUFR, in early 2018 Ukraine and Kazakhstan started sending BUFR reports. Coverage for Europe is essentially complete apart from three NMSs (Bulgaria, Moldova and the Former Yugoslav Republic of Macedonia). For some countries stations/reports designated as "additional data" only are received in TAC but not in BUFR. Light blue markers indicate that fewer BUFR reports are received than SYNOP reports - in most cases the BUFR is six-hourly but the SYNOPs are three-hourly. (Unlike TEMP data, below, alphanumeric SYNOP reports reformatted into BUFR are generally acceptable.)
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(Grey: TAC reports but no BUFR, Purple: BUFR reports but no TAC, Red *: position error. Light/dark blue indicates that there are less/more than 60% of the reports available in BUFR.)
BUOY coverage
On 6 June 2016 ECMWF started passively monitoring BUFR BUOY data in its operational system, assimilation of pressure data started in July 2016, many alphanumeric (FM18) reports ceased on 2 November 2016. For drifting buoys the BUFR feed is almost complete now helped by the fact that fewer data producers are involved (there are about 20 Indian and a few Japanese buoys not using the approved template as yet). In mid-2016 there were 51 pressure-reporting buoys reporting in BUFR but not in FM18, some of these were moored buoys including 7 PIRATA or RAMA buoys which also report subsurface temperature and salinity. Template 315008 is used for moored buoys and 315009 for drifting buoys. More details of the marine data can be found in the Marine and ocean observations pages (one issue is the move from 5-digit to 7-digit identifiers, this means that some newer buoys cannot really be coded using FM18). The plot below does not include the moored buoys that currently report in TM13 (SHIP) code - at some point these will start using the 315008 templateIn December 2018 NOAA moored buoys started reporting in the correct 315008 template (they are mainly close to the US coast, but a few are further offshore). Moored buoys from Canada and the UK still report in SHIP format and are not shown in the plot below. Note that about half the buoys, shown in light blue, do not report pressure (especially those in the tropical Pacific and the Mediterranean, they are deployed to measure SST and currents).
(Grey: TAC reports but no BUFR, Dark blue - BUFR reports including pressure, Light blue - BUFR reports without pressure. Circles/triangles - drifting/moored buoys.)
Ship data
In 2017/18 a number of European ships started using new EUCAWS hardware and software. They report (with identifier EUC*) in BUFR only.
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Most Argo reports are available in BUFR, with higher vertical resolution. Argo buoys stoped reporting in the alphanumeric TESAC code on 1 July 2018.
Radiosonde coverage
About 73% 70% of stations report in BUFR, about 42% 43% report native BUFR with roughly 31% 27% reporting reformatted TEMP (see below). The proportion of native high-resolution reports has grown over the last year (now up to 35%), principally due to the roll out of new software is growing in fits and starts, recently in the USA (2017) and in , Japan (July 2018), parts of South America (2018) and some Russian stations (~Nov 2018). A few 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). In late 2017 Finland stopped reporting alphanumeric TEMPs followed by Norway in January 2018. Stations in France and three in Turkey As of late 2018 stations in Finland, Norway and France no longer provide alphanumeric reports, plus scattered stations elsewhere.
(Grey: TAC reports but no BUFR, Purple: BUFR reports but no TAC, Red *: position error. Blue: both BUFR and TAC, light blue indicates fewer ascents in BUFR. Triangle - ship report, X - wind-only report.)
The plot below distinguishes native BUFR (stations reporting valid radiosonde drift positions): high/low resolution (dark/light blue, using 300 level threshold) from reformatted TEMP (orange). There are now high resolution reports from all continents.
Almost all reformatted TEMP reports are sent as separate parts (A/B/C/D), this is contrary to the BUFR coding rules (there should be a single report containing data for the whole ascent) and reformatted TEMP reports are regarded as unusable by ECMWF and most other NWP centres. BUFR reports generated directly from the radiosonde raw data are much better.