Editorial Type:
Article
Article Type:
Research Article

Assimilation of GPS Radio Occultation Data for an Intense Atmospheric River with the NCEP Regional GSI System

Zaizhong Ma State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China, and University Corporation for Atmospheric Research, Boulder, Colorado

Search for other papers by Zaizhong Ma in
Current site
Google Scholar
PubMed Close
,
Ying-Hwa Kuo University Corporation for Atmospheric Research, Boulder, Colorado

Search for other papers by Ying-Hwa Kuo in
Current site
Google Scholar
PubMed Close
,
F. Martin Ralph NOAA/Earth System Research Laboratory/Physical Sciences Division, Boulder, Colorado

Search for other papers by F. Martin Ralph in
Current site
Google Scholar
PubMed Close
,
Paul J. Neiman NOAA/Earth System Research Laboratory/Physical Sciences Division, Boulder, Colorado

Search for other papers by Paul J. Neiman in
Current site
Google Scholar
PubMed Close
,
Gary A. Wick NOAA/Earth System Research Laboratory/Physical Sciences Division, Boulder, Colorado

Search for other papers by Gary A. Wick in
Current site
Google Scholar
PubMed Close
,
Ellen Sukovich NOAA/Earth System Research Laboratory/Physical Sciences Division, Boulder, Colorado

Search for other papers by Ellen Sukovich in
Current site
Google Scholar
PubMed Close
, and
Bin Wang State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China

Search for other papers by Bin Wang in
Current site
Google Scholar
PubMed Close
Print Publication:
01 Jul 2011
DOI:
https://doi.org/10.1175/2011MWR3342.1
Page(s):
2170–2183
Restricted access

Abstract

This paper uses a case study to explore the potential of Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) and Challenging Minisatellite Payload (CHAMP) global positioning system (GPS) radio occultation (RO) satellite data over the eastern Pacific Ocean to improve analyses and mesoscale forecasts of landfalling atmospheric rivers (ARs) along the U.S. West Coast. The case study is from early November 2006 and was a very high-impact event in the Pacific Northwest where it created torrential rainfall and severe flooding. Recent studies have shown that the COSMIC data offshore have the ability to better define the vertical and horizontal structure of the strong AR. This paper extends the earlier work by assessing the impact of assimilating the COSMIC data into the Advanced Research Weather Research and Forecasting (ARW-WRF) mesoscale numerical model (using a nested mode with 36-, 12-, and 4-km grid sizes) on a key 24-h forecast.

The data are assimilated using NCEP’s Gridpoint Statistical Interpolation (GSI), and impacts are evaluated using Special Sensor Microwave Imager (SSM/I) satellite observations over the ocean and precipitation observations over land. The assimilation of GPS RO soundings made use of a local refractivity observation operator as well as an advanced nonlocal excess phase observation operator that considers the effects of atmospheric horizontal gradients. The results show that the assimilation of GPS RO soundings improved the moisture analysis for this AR event. This result supports conclusions from earlier observing systems simulation experiment (OSSE) studies, but in a real event. The use of a nonlocal excess phase observation operator can produce larger and more robust analysis increments. Although this is a single case study, the results are likely representative of the potential impacts of assimilating COSMIC data in other extreme AR and precipitation events and in other regions affected by landfalling ARs, for example, western Europe, western South America, and New Zealand.

Corresponding author address: Dr. Ying-Hwa Kuo, National Center for Atmospheric Research, Mesoscale and Microscale Meteorology Division, P.O. Box 3000, Boulder, CO 80307-3000. E-mail: kuo@ucar.edu

Abstract

This paper uses a case study to explore the potential of Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) and Challenging Minisatellite Payload (CHAMP) global positioning system (GPS) radio occultation (RO) satellite data over the eastern Pacific Ocean to improve analyses and mesoscale forecasts of landfalling atmospheric rivers (ARs) along the U.S. West Coast. The case study is from early November 2006 and was a very high-impact event in the Pacific Northwest where it created torrential rainfall and severe flooding. Recent studies have shown that the COSMIC data offshore have the ability to better define the vertical and horizontal structure of the strong AR. This paper extends the earlier work by assessing the impact of assimilating the COSMIC data into the Advanced Research Weather Research and Forecasting (ARW-WRF) mesoscale numerical model (using a nested mode with 36-, 12-, and 4-km grid sizes) on a key 24-h forecast.

The data are assimilated using NCEP’s Gridpoint Statistical Interpolation (GSI), and impacts are evaluated using Special Sensor Microwave Imager (SSM/I) satellite observations over the ocean and precipitation observations over land. The assimilation of GPS RO soundings made use of a local refractivity observation operator as well as an advanced nonlocal excess phase observation operator that considers the effects of atmospheric horizontal gradients. The results show that the assimilation of GPS RO soundings improved the moisture analysis for this AR event. This result supports conclusions from earlier observing systems simulation experiment (OSSE) studies, but in a real event. The use of a nonlocal excess phase observation operator can produce larger and more robust analysis increments. Although this is a single case study, the results are likely representative of the potential impacts of assimilating COSMIC data in other extreme AR and precipitation events and in other regions affected by landfalling ARs, for example, western Europe, western South America, and New Zealand.

Corresponding author address: Dr. Ying-Hwa Kuo, National Center for Atmospheric Research, Mesoscale and Microscale Meteorology Division, P.O. Box 3000, Boulder, CO 80307-3000. E-mail: kuo@ucar.edu
Save
Cover Monthly Weather Review
Monthly Weather Review

  • Ahmad, B., and G. L. Tyler, 1998: The two-dimensional resolution kernel associated with retrieval of ionospheric and atmospheric refractivity profiles by Abelian inversion of radio occultation phase data. Radio Sci., 33, 129–142.

    • Search Google Scholar
    • Export Citation

  • Anthes, R. A., and Coauthors, 2008: The COSMIC/FORMOSAT-3 mission: Early results. Bull. Amer. Meteor. Soc., 89, 313–333.

  • Bao, J.-W., S. A. Michelson, P. J. Neiman, F. M. Ralph, and J. M. Wilczak, 2006: Interpretation of enhanced integrated water-vapor bands associated with extratropical cyclones: Their formation and connection to tropical moisture. Mon. Wea. Rev., 134, 1063–1080.

    • Search Google Scholar
    • Export Citation

  • Bernardet, L., and Coauthors, 2008: The Developmental Testbed Center and its winter forecasting experiment. Bull. Amer. Meteor. Soc., 89, 611–627.

    • Search Google Scholar
    • Export Citation

  • Cucurull, L., L. C. Derber, R. Treadon, and R. J. Purser, 2007: Assimilation of global positioning system radio occultation observations into NCEP’s Global Data Assimilation System. Mon. Wea. Rev., 135, 3174–3193.

    • Search Google Scholar
    • Export Citation

  • Daly, C., R. P. Neilson, and D. L. Phillips, 1994: A statistical-topographic model for mapping climatological precipitation over mountainous terrain. J. Appl. Meteor., 33, 140–158.

    • Search Google Scholar
    • Export Citation

  • Hajj, G. A., and Coauthors, 2004: CHAMP and SAC-C atmospheric occultation results and intercomparisons. J. Geophys. Res., 109, D06109, doi:10.1029/2003JD003909.

    • Search Google Scholar
    • Export Citation

  • Hollinger, J. P., J. L. Perirce, and G. A. Poe, 1990: SSM/I instrument evaluation. IEEE Trans. Geosci. Remote Sens., 28, 781–790.

  • Kuo, Y.-H., S. V. Sokolovskiy, R. A. Anthes, and F. Vandenberghe, 2000: Assimilation of GPS radio occultation data for numerical weather prediction. Terr. Atmos. Ocean. Sci., 11, 157–186.

    • Search Google Scholar
    • Export Citation

  • Kuo, Y.-H., T.-K. Wee, S. Sokolovskiy, C. Rocken, W. Schreiner, D. Hunt, and R. A. Anthes, 2004: Inversion and error estimation of GPS radio occultation data. J. Meteor. Soc. Japan, 82, 507–531.

    • Search Google Scholar
    • Export Citation

  • Kuo, Y.-H., H. Liu, Y.-R. Guo, C.-T. Terng, and Y.-T. Lin, 2009: Impact of FORMOSAT-3/COSMIC data on typhoon and mei-yu prediction. Recent Progress in Atmospheric Sciences: Applications to the Asia-Pacific Region, K.-N. Liou and M.-D. Chou, Eds., World Scientific, 458–483.

    • Search Google Scholar
    • Export Citation

  • Liu, H., J. L. Anderson, Y. H. Kuo, C. Snyder, and A. Caya, 2008: Evaluation of a nonlocal quasi-phase observation operator in assimilation of CHAMP radio occultation refractivity with WRF. Mon. Wea. Rev., 136, 242–256.

    • Search Google Scholar
    • Export Citation

  • Ma, Z., Y.-H. Kuo, B. Wang, W.-S. Wu, and S. Sokolovskiy, 2009: Comparison of local and nonlocal observation operators for the assimilation of GPS RO data with the NCEP GSI system: An OSSE study. Mon. Wea. Rev., 137, 3575–3587.

    • Search Google Scholar
    • Export Citation

  • Neiman, P. J., F. M. Ralph, G. A. Wick, Y.-H. Kuo, T.-K. Wee, Z. Ma, G. H. Taylor, and M. D. Dettinger, 2008a: Diagnosis of an intense atmospheric river impacting the Pacific Northwest: Storm summary and offshore vertical structure observed with COSMIC satellite retrievals. Mon. Wea. Rev., 136, 4398–4420.

    • Search Google Scholar
    • Export Citation

  • Neiman, P. J., F. M. Ralph, G. A. Wick, J. Lundquist, and M. D. Dettinger, 2008b: Meteorological characteristics and overland precipitation impacts of atmospheric rivers affecting the West Coast of North America based on eight years of SSM/I satellite observations. J. Hydrometeor., 9, 22–47.

    • Search Google Scholar
    • Export Citation

  • Parrish, D. F., and J. C. Derber, 1992: The National Meteorological Center’s spectral statistical-interpolation analysis system. Mon. Wea. Rev., 120, 1747–1763.

    • Search Google Scholar
    • Export Citation

  • Phinney, R. A., and D. L. Anderson, 1968: On the radio occultation method for studying planetary atmospheres. J. Geophys. Res., 73 (5), 1819–1827.

    • Search Google Scholar
    • Export Citation

  • Ralph, F. M., P. J. Neiman, and G. A. Wick, 2004: Satellite and CALJET aircraft observations of atmospheric rivers over the eastern North Pacific Ocean during the winter of 1997/98. Mon. Wea. Rev., 132, 1721–1745.

    • Search Google Scholar
    • Export Citation

  • Ralph, F. M., and Coauthors, 2005: Improving short-term (0–48 hour) cool-season quantitative precipitation forecasting: Recommendations from a USWRP workshop. Bull. Amer. Meteor. Soc., 86, 1619–1632.

    • Search Google Scholar
    • Export Citation

  • Ralph, F. M., P. J. Neiman, G. A. Wick, S. I. Gutman, M. D. Dettinger, D. R. Cayan, and A. B. White, 2006: Flooding on California’s Russian River: Role of atmospheric rivers. Geophys. Res. Lett., 33, L13801, doi:10.1029/2006GL026689.

    • Search Google Scholar
    • Export Citation

  • Ralph, F. M., E. Sukovich, D. Reynolds, M. Dettinger, S. Weagle, W. Clark, and P. J. Neiman, 2010: Assessment of extreme quantitative precipitation forecasts and development of regional extreme event thresholds using data from HMT-2006 and COOP observers. J. Hydrometeor., 11, 1286–1304.

    • Search Google Scholar
    • Export Citation

  • Rocken, C., Y. H. Kuo, W. S. Schreiner, D. Hunt, S. Sokolovskiy, and C. McCormick, 2000: COSMIC system description. Terr. Atmos. Ocean. Sci., 11, 21–52.

    • Search Google Scholar
    • Export Citation

  • Skamarock, W. C., J. B. Klemp, J. Dudhia, D. O. Gill, D. M. Barker, W. Wang, and J. G. Powers, 2005: A description of the advanced research WRF version 2. NCAR Tech. Note NCAR/TN-468+STR, 100 pp.

    • Search Google Scholar
    • Export Citation

  • Smith, E. K., and S. Weintraub, 1953: The constants in the equation for atmospheric refractivity index at radio frequencies. Proc. IRE, 41, 1035–1037.

    • Search Google Scholar
    • Export Citation

  • Sokolovskiy, S., Y. H. Kuo, and W. Wang, 2005a: Assessing the accuracy of a linearized observation operator for assimilation of the Abel-retrieved refractivity: Case simulation with high-resolution weather model. Mon. Wea. Rev., 133, 2200–2212.

    • Search Google Scholar
    • Export Citation

  • Sokolovskiy, S., Y. H. Kuo, and W. Wang, 2005b: Evaluation of a linear phase observation operator with CHAMP radio occultation data and high-resolution regional analysis. Mon. Wea. Rev., 133, 3053–3059.

    • Search Google Scholar
    • Export Citation

  • Sokolovskiy, S., Y.-H. Kuo, C. Rocken, W. S. Schreiner, D. Hunt, and R. A. Anthes, 2006: Monitoring the atmospheric boundary layer by GPS radio occultation signals recorded in the open-loop mode. Geophys. Res. Lett., 33, L12813, doi:10.1029/2006GL025955.

    • Search Google Scholar
    • Export Citation

  • Stohl, A., C. Forster, and H. Sodemann, 2008: Remote sources of water vapor forming precipitation on the Norwegian west coast at 60°N—A tale of hurricanes and an atmospheric river. J. Geophys. Res., 113, D05102, doi:10.1029/2007JD009006.

    • Search Google Scholar
    • Export Citation

  • Ware, M., and Coauthors, 1996: GPS sounding of the atmosphere from low earth orbit: Preliminary results. Bull. Amer. Meteor. Soc., 77, 19–40.

    • Search Google Scholar
    • Export Citation

  • Wentz, F. J., 1995: The intercomparison of 53 SSM/I water vapor algorithms. Remote Sensing Systems Tech. Rep., 19 pp.

  • Wickert, J., and Coauthors, 2001: Atmosphere sounding by GPS radio occultation: First results from CHAMP. Geophys. Res. Lett., 28 (17), 3263–3266.

    • Search Google Scholar
    • Export Citation

  • Wick, G. A., Y.-H. Kuo, F. M. Ralph, T.-K. Wee, and P. J. Neiman, 2008: Intercomparison of integrated water vapor retrievals from SSM/I and COSMIC. Geophys. Res. Lett., 35, L21805, doi:10.1029/2008GL035126.

    • Search Google Scholar
    • Export Citation

  • Wu, W.-S., R. J. Purser, and D. F. Parrish, 2002: Three-dimensional variational analysis with spatially inhomogeneous covariances. Mon. Wea. Rev., 130, 2905–2916.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 651 286 12
PDF Downloads 417 151 15