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World Meteorological Organization. Intergovernmental Oceanographic Commission of UNESCO. Ship Observations Team ~ integrating and coordinating international ship-based observing programmes for JCOMM ~. VOS Communications Problems and Errors. SOT-IV 16-21 April 2007, Geneva, Switzerland
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World Meteorological Organization Intergovernmental Oceanographic Commission of UNESCO Ship Observations Team~ integrating and coordinating international ship-based observing programmes for JCOMM ~ VOS Communications Problems and Errors SOT-IV 16-21 April 2007, Geneva, Switzerland Sarah North
SOT IV- VOS Communications Problems and Errors • This report addresses coding and transmission errors that have been noted for observations sent via Goonhilly Inmarsat LES • Approx 300 observations each month are being rejected by the Met Office’s observation handling software • Manual intervention is possible to correct some of these coding errors. However, because resources are limited, many of these errors are not followed up. • It is understood that similar coding and transmission problems are being encountered by other NMS that host Inmarsat LES
SOT IV- VOS Communications Problems and Errors Typical rejections … • BBXX or call sign not included in message. • Empty transmissions with no data. • Using 4 figure dew point groups. • Sending phenomena reports or other general messages via Special Access Code 41 • Variable group lengths – e.g a 6 figure longitude group, and other 1,2,3,4 and 10 figure groups • Using /’s between groups • Late date/time groups. • Use of O instead of 0 • Using 6 figure date/time group – reporting month, day and hour, and omitting the wind indicator. • Using 7 figure date/time group, possibly month being added to beginning of group. • Message sent in Hex with no BBXX. • Adding an extra space in one of the 5 figure groups • Using 6 and 4 figure groups and missing temperature and dew point group • Putting in 6 figure groups (mainly extra / in the 8 group) • Missing out a space between 7 and 8 groups and adding a space in the 8 group (e.g. 7002289 ///). • Messages being received as 10 figure groups. • Invalid KKKK group added at end of message.
SOT IV- VOS Communications Problems and Errors Number & Percentage of Rejections November 2006 and January 2007
SOT IV-VOS Communications Problems and Errors What can be done to resolve this ongoing problem? … • Quality controls in electronic logbooks (TurboWin, SEAS etc) will increasingly help to reduce the problem • Whilst we have an abundance of monitoring feedback systems for observation quality problems, there is no formal mechanism for feeding back coding or transmission errors to PMOs or observers • Subject to resources, NMS could perhaps issue details of errors via the PMO and VOS mailing lists run by JCOMMOPS • Some NMS may be able to establish data processing software systems to automatically relay rejected messages back to the VOS focal points SOT to provide guidance, as appropriate…