The quality of satellite precipitable water content data and their impact on analyzed moisture fields

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ILLARI, LODOVICA (2011)

The quality of satellite Precipitable Water Content (PWC) moisture data is assessed by comparing them with radiosondes and the first-guess humidity field from the ECMWF operational model. Collocation studies show that PWC data from satellites are of comparable quality to radiosonde data and that the error in the inferred relative humidity varies from 15% in the Tropics to 35% in the extra-tropics, similar to the typical error levels of radiosonde humidity data. The model first-guess provides moisture information of comparable accuracy. Using a large sample of radiosonde and first-guess moisture information over North America, the typical forecast error correlation scale for the humidity analysis variable has been found to be 250 km at the surface rising to 300 km at upper levels. Finally, impact studies have shown that the inclusion of satellite PWC data in the ECMWF humidity analysis has a small but beneficial impact on the forecast, especially of the forecast rain in the Tropics.DOI: 10.1111/j.1600-0870.1989.tb00386.x
  • References (26)
    26 references, page 1 of 3

    Atkins, M. J . 1974. The objective analysis of relative humidity. Tellus 26, 663471.

    Cadet, D. 1983. Mean fields of precipitable water over the Indian Ocean during the 1979 Summer Monsoon from TIROS-N sounding and the FGGE data. Tellus 35A, 329-345.

    Chu, R. and Parish, D. 1977. Humidity analyses for operational prediction models at the National Meteorologial Center. N O A A N M C Ofice Note 146.

    Cressman, G . P. 1959. On operational objective analysis system. Mon. Weu. Rev. 87, 367-374.

    Datta, R. K., Heckley, W. A,, Illari, L. and Miller, M. J. 1985. Prediction of monsoon flow over the Indian Subcontinent by the ECMWF model. ECMWF Tech. Memo. No. 133. (Available from ECMWF, Shinfield Park, Reading, UK.)

    Gruber, A. and Watkins, C. D. 1981. Preliminary evaluation of initial atmospheric moisture from the TIROS-N sounding system. In : Sutellire Hydrology (eds. M. Deutsch, D. R. Wiesnet and A. Rango). Minneapolis, Minn.: Amer. Water Res. Assn., 115- 123.

    Hayden, C. M., Smith, W. L. and Woolf, H. M. 1981. Determination of moisture from NOAA polar orbiting satellite sounding radiances. J. Appl. Meteor. 20,45&460.

    Hollingsworth, A,, Shaw, D. B., Liinnberg, P., Illari, L., Arpe, K. and Simmons, A. J. 1986. Monitoring of observations and analysis quality by a data assimilation system. Mon. Weu. Rev. 114, 861-879.

    Hollingsworth, A. and Liinnberg, P. 1986. The statistical structure of short-range forecast errors as determined from radiosonde data. Part I : The wind field. Tellus 38A, 111-1 36.

    Johnson, D. S. 1984. Meteorological parameters derived from space based observing systems. F G G E and after. ECMWF Seminar, September 1984. Vol. 1, 47-108. (Available from ECMWF, Shinfield Park, Reading, UK.)

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