The WIGOS Monitoring Centres that are currently providing quality near-real-time NWP monitoring reports are: DWD, ECMWF, JMA and NCEP for surface land stations and upper-air land stations. As it is based on the feedback from the assimilation systems, the monitoring information provided by the NWP Centres reflects the main characteristics - strengths and weaknesses - of each system. By combining the information across Centres the WDQMS monitoring tool exploits the strengths of each NWP assimilation system and provides a more robust statement regarding availability and quality than what would be possible from a single NWP centre.
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JMA provides O-B values for all observations available to their assimilation system even for the observations that are not used in the assimilation. It is worth mentioning that they tend to assimilate pressure observations every 3 hours rather than hourly.
5.2. Combined (All)Anchor Section5.2 Section5.2
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A summary combining all the performance reports from the different WIGOS monitoring centres Monitoring Centres is generated when option “All” is selected. This means that for each and every period, variable and monitoring category (availability and quality), there is a combined performance report available. The overarching rule for aggregating the information across NWP Centres is that the best data availability and quality result is used to generate a combined performance report. The combined availability performance report will be generated by taking the maximum availability result amongst all Centres (i.e. the information will come from the Centre with the highest total in the period). Regarding the quality, the result that will be retained is the one from the NWP model whose background field is closest to the observed value (i.e., the information will come from the Centre with the smallest O-B departures averaged over the period of interest).