• Bauer, P., A. Khain, A. Pokrovsky, R. Meneghini, C. Kummerow, F. Marzano, and J. P. V. P. Baptista. 2000. Combined cloud–microwave radiative transfer modeling of stratiform rainfall. J. Atmos. Sci. 57:10821104.

    • Search Google Scholar
    • Export Citation
  • Czekala, H., S. Crewell, C. Simmer, A. Thiele, A. Hornbostel, and A. Schroth. 2001. Interpretation of polarization features in ground-based microwave observations as caused by horizontally aligned oblate raindrops. J. Appl. Meteor. 40:19181932.

    • Search Google Scholar
    • Export Citation
  • English, S. J., R. J. Renshaw, P. C. Dibben, A. J. Smith, P. J. Rayer, C. Poulsen, F. W. Saunders, and J. R. Eyre. 2000. A comparison of the impact of TOVS and ATOVS satellite sounding data on the accuracy of numerical weather forecasts. Quart. J. Roy. Meteor. Soc. 126:29112931.

    • Search Google Scholar
    • Export Citation
  • Evans, K. F., J. Turk, T. Wong, and G. L. Stephens. 1995. A Bayesian approach to microwave precipitation profile retrieval. J. Appl. Meteor. 34:260279.

    • Search Google Scholar
    • Export Citation
  • Eyre, J. R., G. A. Kelly, A. P. McNally, E. Andersson, and A. Persson. 1993. Assimilation of TOVS radiance information through one-dimensional variational analysis. Quart. J. Roy. Meteor. Soc. 119:14271463.

    • Search Google Scholar
    • Export Citation
  • Greenwald, T. J., R. Hertenstein, and T. Vukicevic. 2002. An all-weather observational operator for radiance data assimilation with mesoscale forecast models. Mon. Wea. Rev. 130:18821897.

    • Search Google Scholar
    • Export Citation
  • Hou, A. Y., S. Q. Zhang, A. M. da Silva, W. S. Olson, C. D. Kummerow, and J. Simpson. 2001. Improving global analysis and short-range forecast using rainfall and moisture observations derived from TRMM and SSM/I passive microwave sensors. Bull. Amer. Meteor. Soc. 82:659679.

    • Search Google Scholar
    • Export Citation
  • Joseph, J. H., W. J. Wiscombe, and J. A. Weinman. 1976. The delta-Eddington approximation for radiative flux transfer. J. Atmos. Sci. 33:24522459.

    • Search Google Scholar
    • Export Citation
  • Kummerow, C. D. 1993. On the accuracy of the Eddington approximation for radiative transfer in the microwave frequencies. J. Geophys. Res. 98:27572765.

    • Search Google Scholar
    • Export Citation
  • Liebe, H. J., P. Rosenkranz, and G. A. Hufford. 1992. Atmospheric 60 GHz oxygen spectrum: New laboratory measurements and line parameters. J. Quant. Spectrosc. Radiat. Transfer 48:629643.

    • Search Google Scholar
    • Export Citation
  • Liu, G. 1998. A fast and accurate model for microwave radiance calculations. J. Meteor. Soc. Japan 76:335343.

  • Liu, Q. and C. Simmer. 1996. Polarization and intensity in microwave radiative transfer. Contrib. Atmos. Phys. 69:535545.

  • Liu, Q. and F. Weng. 2002. A microwave polarimetric two-stream radiative transfer model. J. Atmos. Sci. 59:23962402.

  • McMillin, L. M., L. J. Crone, M. D. Goldberg, and T. J. Kleespies. 1995. Atmospheric transmittance of an absorbing gas, 4. OPTRAN: A computationally fast and accurate transmittance model for absorbing gases with fixed and variable mixing ratios at variable viewing angles. Appl. Opt. 34:62696274.

    • Search Google Scholar
    • Export Citation
  • Petty, G. W. 1994. Physical retrievals of over-ocean rain rate from multichannel microwave imagery. 1. Theoretical characteristics of normalized polarization and scattering indexes. Meteor. Atmos. Phys 54:7999.

    • Search Google Scholar
    • Export Citation
  • Smith, E. A., P. Bauer, F. S. Marzano, C. D. Kummerow, D. McKague, A. Mugnai, and G. Panegrossi. 2002. Intercomparison of microwave radiative transfer models for precipitating clouds. IEEE Trans. Geosci. Remote Sens. 40:541549.

    • Search Google Scholar
    • Export Citation
  • Spencer, R. W., B. B. Hinton, and W. S. Olson. 1983. Nimbus-7 37 GHz radiances correlated with radar rain rates over the Gulf of Mexico. J. Climate Appl. Meteor. 22:20952099.

    • Search Google Scholar
    • Export Citation
  • Weinman, J. A. and P. J. Guetter. 1977. Determination of rainfall distributions from microwave radiation measured by the Nimbus 6 ESMR. J. Appl. Meteor. 16:437442.

    • Search Google Scholar
    • Export Citation
  • Wendisch, M. and W. von Hoyningen-Huene. 1991. High speed version of the method of successive order of scattering and its application to remote sensing. Contrib. Atmos. Phys. 64:8391.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 64 30 0
PDF Downloads 28 14 0

Fast Computation of Microwave Radiances for Data Assimilation Using the “Successive Order of Scattering” Method

View More View Less
  • a Cooperative Institute for Meteorological Satellite Studies, University of Wisconsin—Madison, Madison, Wisconsin
  • | b Department of Oceanic and Atmospheric Sciences, University of Wisconsin—Madison, Madison, Wisconsin
  • | c National Environmental Satellite, Data, and Information Service, National Oceanic and Atmospheric Administration, Madison, Wisconsin
Restricted access

Abstract

Fast and accurate radiative transfer (RT) models are crucial in making use of microwave satellite data feasible under all weather conditions in numerical weather prediction (NWP) data assimilation. A multistream “successive order of scattering” (SOS) RT model has been developed to determine its suitability in NWP for computing microwave radiances in precipitating clouds. Results show that the two-stream SOS model is up to 10 times as fast as and is as accurate as the commonly used delta-Eddington model for weaker scattering [column scattering optical depth (CSOD) < 0.01], but it is less accurate and is slower for higher frequencies (>30 GHz) in cases of moderately strong to strong scattering (CSOD > 5). If two- and four-stream SOS models are used in combination, however, it was found that 85.5-GHz brightness temperatures computed for 1° × 1° global forecast fields were more accurate (<0.5 K vs 1.5 K for CSOD > 0.1) and were executed 4 times as fast as the delta-Eddington model. The SOS method has been demonstrated as an alternative to other fast RT models for providing accurate and very rapid multiple-scattering calculations at thermal wavelengths for remote sensing studies and demanding applications such as operational NWP data assimilation.

Corresponding author address: Dr. Thomas Greenwald, CIMSS/ SSEC, University of Wisconsin—Madison, 1225 W. Dayton St., Madison, WI 53706. tomg@ssec.wisc.edu

Abstract

Fast and accurate radiative transfer (RT) models are crucial in making use of microwave satellite data feasible under all weather conditions in numerical weather prediction (NWP) data assimilation. A multistream “successive order of scattering” (SOS) RT model has been developed to determine its suitability in NWP for computing microwave radiances in precipitating clouds. Results show that the two-stream SOS model is up to 10 times as fast as and is as accurate as the commonly used delta-Eddington model for weaker scattering [column scattering optical depth (CSOD) < 0.01], but it is less accurate and is slower for higher frequencies (>30 GHz) in cases of moderately strong to strong scattering (CSOD > 5). If two- and four-stream SOS models are used in combination, however, it was found that 85.5-GHz brightness temperatures computed for 1° × 1° global forecast fields were more accurate (<0.5 K vs 1.5 K for CSOD > 0.1) and were executed 4 times as fast as the delta-Eddington model. The SOS method has been demonstrated as an alternative to other fast RT models for providing accurate and very rapid multiple-scattering calculations at thermal wavelengths for remote sensing studies and demanding applications such as operational NWP data assimilation.

Corresponding author address: Dr. Thomas Greenwald, CIMSS/ SSEC, University of Wisconsin—Madison, 1225 W. Dayton St., Madison, WI 53706. tomg@ssec.wisc.edu

Save