Mark Smees, Catherine Gaffard, John Nash, (Met Office). GCOS/CIMO/WMO Training Workshop on GUAN Upper-Air-Observations for RA1 (Africa) Mark Smees, Catherine Gaffard, John Nash, (Met Office). Upper-Air team, Observations Research and Development, Met Office, UK After the launches of the radiosondes a review of the results was held. The results were processed using the RSKOMP radiosonde comparison software. The 2 graphs show the comparison between the Vaisala RS92, MODEM M2K2 and the InterMet BAT-16G radiosondes, for a multi-rig flight on 10/10/07 at 12:54 UTC (14:54 Local). The temperature and humidity graph to the left shows the Vaisala RS92 in yellow, InterMet BAT-16G in blue and the MODEM M2K2 in Red. In the N-S and E-W wind graph below the Vaisala RS92 is in yellow, InterMet BAT-16G in blue and the MODEM in red. Also during the second week there were lectures on: “Results from WMO Radiosonde Comparison, Mauritius” Changes made to sensors after the WMO trial in Mauritius New ground-based observing systems Conclusions Poor burst heights suggest that more attention is needed to be paid to balloon handling procedures and storage The InterMet (SA) radiosonde provided measurements close to the other manufactures, so it appeared that performance in South Africa was anomalous, and the problem is now rectified. The workshop produced positive results in performance and proves that there is benefit to this type of workshop. The workshop was a great success and all the participants, manufacturers and lectures learnt something new, as well as having an enjoyable week, with innovative ideas to take back to their countries. Indeed the GCOS network monitoring report by NCEP indicates that there have been improvements since the workshop. I would like to thank KNMI who provided the funding, The Met Office for providing the UK lecturing staff, and the Namibian Meteorological Service who organised the workshop, especially Mr. Benjamin Rebang, Mr. Martin Philander, Mr. Willem Gaoëb, and Ms. Sieglinde Somses, who facilitated our requirements. Met Office FitzRoy Road, Exeter, Devon, EX1 3PB United Kingdom Tel: 01392 885680 Fax: 01392 885681 Email: alec.bennett@metoffice.gov.uk © Crown copyright 2008 Met Office and the Met Office logo are registered trademarks