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Article dans une revue
A high quality reprocessed ground-based GPS dataset for atmospheric process studies, radiosonde and model evaluation, and reanalysis of HyMeX Special Observing Period
Abstract : In the framework of the HyMeX project, measurements from more than one thousand ground-based GPS receivers located in the north-western Mediterranean area are reprocessed using a single GPS software for the period from 1st September 2012 to 31 March 2013. A special screening procedure is developed for the removal of outliers in the GPS ZTD data. ZTD data are converted to IWV using surface pressure information from AROME-WMED operational analysis. The reprocessed ZTD and IWV data are used to assess the accuracy of the near real time E-GVAP ZTD data assimilated in operational NWP systems and to validate the IWV data from AROME-WMED operational analysis and AROME-WMED reanalysis 1, and from radiosonde observations. The mean differences between E-GVAP and reprocessed ZTD data are not negligible and lie in the range from −3 to +3 mm. The standard deviations of differences are between 4 and 8 mm. The comparisons of IWV from AROME-WMED analyses and the reprocessed GPS data show high quality of the analyses where operational GPS data are assimilated and lower quality where no GPS data are assimilated. Small but significant biases are found in the radiosonde data at daytime (−0.5 to +1.4 kg m−2), but their origin is not determined so far. Thanks to the high spatial density of the reprocessed GPS stations, both the large scale and small scale variations in IWV can be documented. The case of HyMeX Intensive Observing Period 8 is presented as an example of heavy precipitation event. This work suggests that improved quality of the humidity fields can be expected of the future AROME-WMED reanalysis 2 as a result of the assimilation of the reprocessed GPS data.
https://hal.archives-ouvertes.fr/hal-01236899
Contributeur : Annick Billon-Coat <>
Soumis le : mercredi 2 décembre 2015 - 12:13:43
Dernière modification le : vendredi 13 décembre 2019 - 10:42:13
Contributeur : Annick Billon-Coat <>
Soumis le : mercredi 2 décembre 2015 - 12:13:43
Dernière modification le : vendredi 13 décembre 2019 - 10:42:13