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Article Type:
Research Article

An Impact Assessment of GPS Radio Occultation Data on Prediction of a Rapidly Developing Cyclone over the Southern Ocean

Shu-Ya Chen University Corporation for Atmospheric Research, Boulder, Colorado

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Tae-Kwon Wee University Corporation for Atmospheric Research, Boulder, Colorado

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Ying-Hwa Kuo University Corporation for Atmospheric Research, and National Center for Atmospheric Research, Boulder, Colorado

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David H. Bromwich Byrd Polar Research Center, The Ohio State University, Columbus, Ohio

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Print Publication:
01 Nov 2014
DOI:
https://doi.org/10.1175/MWR-D-14-00024.1
Page(s):
4187–4206
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Abstract

The impact of global positioning system (GPS) radio occultation (RO) data on an intense synoptic-scale storm that occurred over the Southern Ocean in December 2007 is evaluated, and a synoptic explanation of the assessed impact is offered. The impact is assessed by using the three-dimensional variational data assimilation scheme (3DVAR) of the Weather Research and Forecasting (WRF) Model Data Assimilation system (WRFDA), and by comparing two experiments: one with and the other without assimilating the refractivity data from four different RO missions. Verifications indicate significant positive impacts of the RO data in various measures and parameters as well as in the track and intensity of the Antarctic cyclone. The analysis of the atmospheric processes underlying the impact shows that the assimilation of the RO data yields substantial improvements in the large-scale circulations that in turn control the development of the Antarctic storm. For instance, the RO data enhanced the strength of a 500-hPa trough over the Southern Ocean and prevented the katabatic flow near the coast of East Antarctica from an overintensification. This greatly influenced two low pressure systems of a comparable intensity, which later merged together and evolved into the major storm. The dominance of one low over the other in the merger dramatically changed the track, intensity, and structure of the merged storm. The assimilation of GPS RO data swapped the dominant low, leading to a remarkable improvement in the subsequent storm’s prediction.

Byrd Polar Research Center Contribution Number 1449.

Corresponding author address: Shu-Ya Chen, UCAR COSMIC Program, P.O. Box 3000, Boulder, CO 80307-3000. E-mail: sychen@ucar.edu

Abstract

The impact of global positioning system (GPS) radio occultation (RO) data on an intense synoptic-scale storm that occurred over the Southern Ocean in December 2007 is evaluated, and a synoptic explanation of the assessed impact is offered. The impact is assessed by using the three-dimensional variational data assimilation scheme (3DVAR) of the Weather Research and Forecasting (WRF) Model Data Assimilation system (WRFDA), and by comparing two experiments: one with and the other without assimilating the refractivity data from four different RO missions. Verifications indicate significant positive impacts of the RO data in various measures and parameters as well as in the track and intensity of the Antarctic cyclone. The analysis of the atmospheric processes underlying the impact shows that the assimilation of the RO data yields substantial improvements in the large-scale circulations that in turn control the development of the Antarctic storm. For instance, the RO data enhanced the strength of a 500-hPa trough over the Southern Ocean and prevented the katabatic flow near the coast of East Antarctica from an overintensification. This greatly influenced two low pressure systems of a comparable intensity, which later merged together and evolved into the major storm. The dominance of one low over the other in the merger dramatically changed the track, intensity, and structure of the merged storm. The assimilation of GPS RO data swapped the dominant low, leading to a remarkable improvement in the subsequent storm’s prediction.

Byrd Polar Research Center Contribution Number 1449.

Corresponding author address: Shu-Ya Chen, UCAR COSMIC Program, P.O. Box 3000, Boulder, CO 80307-3000. E-mail: sychen@ucar.edu
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  • Adams, N., 1997: Model prediction performance over the Southern Ocean and coastal region around East Antarctica. Aust. Meteor. Mag., 46, 287–296.

    • Search Google Scholar
    • Export Citation

  • Anderson, J. L., 2010: A non-Gaussian ensemble filter update for data assimilation. Mon. Wea. Rev., 138, 4186–4198, doi:10.1175/2010MWR3253.1.

    • Search Google Scholar
    • Export Citation

  • Anthes, R. A., C. Rocken, and Y.-H. Kuo, 2000: Applications of COSMIC to meteorology and climate. Terr. Atmos. Oceanic Sci., 11, 115–156.

    • 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, doi:10.1175/BAMS-89-3-313.

    • Search Google Scholar
    • Export Citation

  • Aparicio, J. M., and G. Deblonde, 2008: Impact of the assimilation of CHAMP refractivity profiles on Environment Canada global forecasts. Mon. Wea. Rev., 136, 257–275, doi:10.1175/2007MWR1951.1.

    • Search Google Scholar
    • Export Citation

  • Barker, D. M., W. Huang, Y.-R. Guo, A. J. Bourgeois, and Q. N. Xiao, 2004: A three-dimensional variational data assimilation system for MM5: Implementation and initial results. Mon. Wea. Rev., 132, 897–914, doi:10.1175/1520-0493(2004)132<0897:ATVDAS>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Barker, D. M., and Coauthors, 2012: The Weather Research and Forecasting Model’s Community Variational/Ensemble Data Assimilation System: WRFDA. Bull. Amer. Meteor. Soc., 93, 831–843, doi:10.1175/BAMS-D-11-00167.1.

    • Search Google Scholar
    • Export Citation

  • Bouchard, A., F. Rabier, V. Guidard, and F. Karbou, 2010: Enhancements of satellite data assimilation over Antarctica. Mon. Wea. Rev., 138, 2149–2173, doi:10.1175/2009MWR3071.1.

    • Search Google Scholar
    • Export Citation

  • Bromwich, D. H., and T. R. Parish, Eds., 2002: Scientific motivation for the Ross Island Meteorology Experiment (RIME). BPRC Miscellaneous Series M-425, Byrd Polar Research Center, The Ohio State University, Columbus, OH, 14 pp.

  • Bromwich, D. H., D. F. Steinhoff, I. Simmond, K. Keay, and R. L. Fogt, 2011: Climatological aspects of cyclogenesis near Adélie Land Antarctica. Tellus, 63A, 921–938, doi:10.1111/j.1600-0870.2011.00537.x.

    • Search Google Scholar
    • Export Citation

  • Bromwich, D. H., J. P. Nicolas, A. J. Monaghan, M. A. Lazzara, L. M. Keller, G. A. Weidner, and A. B. Wilson, 2013: Central West Antarctica among the most rapidly warming regions on Earth. Nat. Geosci., 6, 139–145, doi:10.1038/ngeo1671.

    • Search Google Scholar
    • Export Citation

  • Bromwich, D. H., J. P. Nicolas, A. J. Monaghan, M. A. Lazzara, L. M. Keller, G. A. Weidner, and A. B. Wilson, 2014: Corrigendum: Central West Antarctica among the most rapidly warming regions on Earth. Nat. Geosci., 7, 76, doi:10.1038/ngeo2016.

    • Search Google Scholar
    • Export Citation

  • Carleton, A. M., and M. Fitch, 1993: Synoptic aspects of Antarctic mesocyclones. J. Geophys. Res., 98, 12 997–13 018, doi:10.1029/92JD02132.

    • Search Google Scholar
    • Export Citation

  • Chen, F., and J. Dudhia, 2001: Coupling an advanced land-surface/hydrology model with the Penn State/NCAR MM5 modeling system. Part I: Model implementation and sensitivity. Mon. Wea. Rev., 129, 569–585, doi:10.1175/1520-0493(2001)129<0569:CAALSH>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Chen, S.-Y., C.-Y. Huang, Y.-H. Kuo, Y.-R. Guo, and S. Sokolovskiy, 2009: Assimilation of GPS refractivity from FORMOSAT-3/COSMIC using a nonlocal operator with WRF 3DVAR and its impact on the prediction of a typhoon event. Terr. Atmos. Oceanic Sci., 20, 133–154, doi:10.3319/TAO.2007.11.29.01(F3C).

    • Search Google Scholar
    • Export Citation

  • Chen, S.-Y., C.-Y. Huang, Y.-H. Kuo, and S. Sokolovskiy, 2011: Observational error estimation of FORMOSAT-3/COSMIC GPS radio occultation data. Mon. Wea. Rev., 139, 853–865, doi:10.1175/2010MWR3260.1.

    • Search Google Scholar
    • Export Citation

  • Chou, M.-D., and M. J. Suarez, 1994: An efficient thermal infrared radiation parameterization for user in general circulation models. NASA Tech. Memo. 104606, Vol. 3, 85 pp.

  • Cucurull, L., 2010: Improvement in the use of an operational constellation of GPS radio occultation receivers in weather forecasting. Wea. Forecasting, 25, 749–767, doi:10.1175/2009WAF2222302.1.

    • Search Google Scholar
    • Export Citation

  • Cucurull, L., Y.-H. Kuo, D. Barker, and S. R. H. Rizvi, 2006: Assessing the impact of simulated COSMIC GPS radio occultation data on weather analysis over the Antarctic: A case study. Mon. Wea. Rev., 134, 3283–3296, doi:10.1175/MWR3241.1.

    • Search Google Scholar
    • Export Citation

  • Cucurull, L., J. 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, doi:10.1175/MWR3461.1.

    • Search Google Scholar
    • Export Citation

  • Cucurull, L., J. C. Derber, and R. J. Purser, 2013: A bending angle forward operator for global positioning system radio occultation measurements. J. Geophys. Res. Atmos., 118, 14–28, doi:10.1029/2012JD017782.

    • Search Google Scholar
    • Export Citation

  • Cucurull, L., R. A. Anthes, and L.-L. Tsao, 2014: Radio occultation observations as anchor observations in numerical weather prediction models and associated reduction of bias corrections in microwave and infrared satellite observations. J. Atmos. Oceanic Technol., 31, 20–32, doi:10.1175/JTECH-D-13-00059.1.

    • Search Google Scholar
    • Export Citation

  • Dee, D. P., and S. Uppala, 2009: Variational bias correction of satellite radiance data in the ERA-Interim reanalysis. Quart. J. Roy. Meteor. Soc., 135, 1830–1841, doi:10.1002/qj.493.

    • Search Google Scholar
    • Export Citation

  • Derber, J. C., and W.-S. Wu, 1998: The use of TOVS cloud-cleared radiances in the NCEP SSI analysis system. Mon. Wea. Rev., 126, 2287–2299, doi:10.1175/1520-0493(1998)126<2287:TUOTCC>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • English, S. J., 2008: The importance of accurate skin temperature in assimilating radiances from satellite sounding instruments. IEEE Trans. Geosci. Remote Sens., 46, 403–408, doi:10.1109/TGRS.2007.902413.

    • 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

  • Healy, S. B., 2008: Forecast impact experiment with a constellation of GPS radio occultation receivers. Atmos. Sci. Lett., 9, 111–118, doi:10.1002/asl.169.

    • Search Google Scholar
    • Export Citation

  • Healy, S. B., and J.-N. Thépaut, 2006: Assimilation experiments with CHAMP GPS radio occultation measurements. Quart. J. Roy. Meteor. Soc., 132, 605–623, doi:10.1256/qj.04.182.

    • Search Google Scholar
    • Export Citation

  • Healy, S. B., J. R. Eyre, M. Hamrud, and J.-N. Thépaut, 2007: Assimilating GPS radio occultation measurements with two-dimensional bending angle observation operators. Quart. J. Roy. Meteor. Soc., 133, 1213–1227, doi:10.1002/qj.63.

    • Search Google Scholar
    • Export Citation

  • Hong, S.-Y., and J.-O. J. Lim, 2006: The WRF single-moment 6-class microphysics scheme (WSM6). J. Korean Meteor. Soc., 42, 129–151.

  • Hong, S.-Y., J. Dudhia, and S.-H. Chen, 2004: A revised approach to ice microphysical processes for the bulk parameterization of clouds and precipitation. Mon. Wea. Rev., 132, 103–120, doi:10.1175/1520-0493(2004)132<0103:ARATIM>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Hoskins, B. J., and K. I. Hodges, 2005: A new perspective on Southern Hemisphere storm tracks. J. Climate, 18, 4108–4129, doi:10.1175/JCLI3570.1.

    • Search Google Scholar
    • Export Citation

  • Huang, C.-Y., Y.-H. Kuo, S.-H. Chen, and F. Vandenberghe, 2005: Improvements in typhoon forecasts with assimilated GPS occultation refractivity. Wea. Forecasting, 20, 931–953, doi:10.1175/WAF874.1.

    • Search Google Scholar
    • Export Citation

  • Huang, C.-Y., and Coauthors, 2010: Impact of GPS radio occultation data assimilation on regional weather predictions. GPS Solut., 14, 35–49, doi:10.1007/s10291-009-0144-1.

    • Search Google Scholar
    • Export Citation

  • Huang, X.-Y., and Coauthors, 2009: Four-dimensional variational data assimilation for WRF: formulation and preliminary results. Mon. Wea. Rev., 137, 299–314, doi:10.1175/2008MWR2577.1.

    • Search Google Scholar
    • Export Citation

  • Janjic, Z. I., 2002: Nonsingular implementation of the Mellor-Yamada level 2.5 scheme in the NCEP Meso Model. NCEP Office Note 437, 61 pp.

  • Kain, J. S., and J. M. Fritsch, 1990: A one-dimensional entraining/detraining plume model and its application in convective parameterization. J. Atmos. Sci., 47, 2784–2802, doi:10.1175/1520-0469(1990)047<2784:AODEPM>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Kain, J. S., and J. M. Fritsch, 1993: Convective parameterization for mesoscale models: The Kain–Fritsch scheme. The Representation of Cumulus Convection in Numerical Models, Meteor. Monogr., No. 24, Amer. Meteor. Soc., 165–170.

  • King, J. C., and J. Turner, 1997: Antarctic Meteorology and Climatology. Cambridge University Press, 409 pp.

  • 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. Oceanic 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, doi:10.2151/jmsj.2004.507.

    • Search Google Scholar
    • Export Citation

  • Kuo, Y.-H., W. S. Schreiner, J. Wang, D. L. Rossiter, and Y. Zhang, 2005: Comparison of GPS radio occultation soundings with radiosondes. Geophys. Res. Lett., 32, L05817, doi:10.1029/2004GL021443.

    • Search Google Scholar
    • Export Citation

  • Lazzara, M. A., G. A. Weidner, L. M. Keller, J. E. Thom, and J. J. Cassano, 2012: Antarctic Automatic Weather Station Program: 30 years of polar observation. Bull. Amer. Meteor. Soc., 93, 1519–1537, doi:10.1175/BAMS-D-11-00015.1.

    • Search Google Scholar
    • Export Citation

  • Lim, E.-P., and I. Simmonds, 2007: Southern Hemisphere winter extratropical cyclone characteristics and vertical organization observed with the ERA-40 data in 1979–2001. J. Climate, 20, 2675–2690, doi:10.1175/JCLI4135.1.

    • Search Google Scholar
    • Export Citation

  • Ma, Z.-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, doi:10.1175/2009MWR2809.1.

    • Search Google Scholar
    • Export Citation

  • Marshall, G. J., V. Lagun, and T. A. Lachlan-Cope, 2002: Changes in Antarctic Peninsula tropospheric temperatures from 1956 to 1999: A synthesis of observations and reanalysis data. Int. J. Climatol., 22, 291–310, doi:10.1002/joc.758.

    • Search Google Scholar
    • Export Citation

  • McMillan, M., A. Shepherd, A. Sunda, K. Briggs, A. Muir, A. Ridout, A. Hogg, and D. Wingham, 2014: Increased ice losses from Antarctica detected by CryoSat-2. Geophys. Res. Lett., 41, 3899–3905, doi:10.1002/2014GL060111.

    • Search Google Scholar
    • Export Citation

  • McNally, A. P., and P. D. Watts, 2003: A cloud detection algorithm for high spectral resolution infrared sounders. Quart. J. Roy. Meteor. Soc., 129, 3411–3423, doi:10.1256/qj.02.208.

    • Search Google Scholar
    • Export Citation

  • Mellor, G. L., and T. Yamada, 1982: Development of a turbulence closure model for geophysical fluid problems. Rev. Geophys., 20, 851–875, doi:10.1029/RG020i004p00851.

    • Search Google Scholar
    • Export Citation

  • Mlawer, E. J., S. J. Taubman, P. D. Brown, M. J. Iacono, and S. A. Clough, 1997: Radiative transfer for inhomogeneous atmospheres: RRTM, a validated correlated-k model for the longwave. J. Geophys. Res., 102, 16 663–16 682, doi:10.1029/97JD00237.

    • Search Google Scholar
    • Export Citation

  • Nicolas, J. P., and D. H. Bromwich, 2011a: Climate of West Antarctica and influence of marine air intrusions. J. Climate, 24, 49–67, doi:10.1175/2010JCLI3522.1.

    • Search Google Scholar
    • Export Citation

  • Nicolas, J. P., and D. H. Bromwich, 2011b: Precipitation changes in high southern latitudes from global reanalyses: A cautionary tale. Surv. Geophys., 32, 475–494, doi:10.1007/s10712-011-9114-6.

    • Search Google Scholar
    • Export Citation

  • Oppenheimer, M., 1998: Global warming and the stability of the west Antarctic ice sheet. Nature, 393, 325–332, doi:10.1038/30661.

  • Parish, T. R., and D. H. Bromwich, 2007: Re-examination of the near-surface air flow over the Antarctic continent and implications on atmospheric circulations at high southern latitudes. Mon. Wea. Rev., 135, 1961–1973, doi:10.1175/MWR3374.1.

    • Search Google Scholar
    • Export Citation

  • Pavolonis, M. J., and J. R. Key, 2003: Antarctic cloud radiative forcing at the surface estimated from the AVHRR Polar Pathfinder and ISCCP D1 datasets, 1985–1993. J. Appl. Meteor., 42, 827–840, doi:10.1175/1520-0450(2003)042<0827:ACRFAT>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Pendlebury, S. F., N. D. Adams, T. L. Hart, and J. Turner, 2003: Numerical weather prediction model performance over the high southern latitudes. Mon. Wea. Rev., 131, 335–353, doi:10.1175/1520-0493(2003)131<0335:NWPMPO>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Poli, P., S. B. Healy, F. Rabier, and J. Pailleux, 2008: Preliminary assessment of the scalability of GPS radio occultations impact in numerical weather prediction. Geophys. Res. Lett., 35, L23811, doi:10.1029/2008GL035873.

    • Search Google Scholar
    • Export Citation

  • Powers, J. G., K. W. Manning, D. H. Bromwich, J. J. Cassano, and A. M. Cayette, 2012: A decade of Antarctic science support through AMPS. Bull. Amer. Meteor. Soc., 93, 1699–1712, doi:10.1175/BAMS-D-11-00186.1.

    • Search Google Scholar
    • Export Citation

  • Pritchard, H. D., S. R. M. Ligtenberg, H. A. Fricker, D. G. Vaughan, M. R. van den Broeke, and L. Padman, 2012: Antarctic ice-sheet loss driven by basal melting of ice shelves. Nature, 484, 502–505, doi:10.1038/nature10968.

    • Search Google Scholar
    • Export Citation

  • Rennie, M. P., 2010: The impact of GPS radio occultation assimilation at the Met Office. Quart. J. Roy. Meteor. Soc., 136, 116–131, doi:10.1002/qj.521.

    • Search Google Scholar
    • Export Citation

  • Rocken, C., and Coauthors, 1997: Analysis and validation of GPS/ MET data in the neutral atmosphere. J. Geophys. Res., 102, 29 849–29 866, doi:10.1029/97JD02400.

    • Search Google Scholar
    • Export Citation

  • Shepherd, A., and Coauthors, 2012: A reconciled estimate of ice-sheet mass balance. Science, 338, 1183–1189, doi:10.1126/science.1228102.

    • Search Google Scholar
    • Export Citation

  • Simmonds, I., K. Keay, and E.-P. Lim, 2003: Synoptic activity in the seas around Antarctica. Mon. Wea. Rev., 131, 272–288, doi:10.1175/1520-0493(2003)131<0272:SAITSA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Simmons, A. J., and A. Hollingsworth, 2002: Some aspects of the improvement in skill of numerical weather prediction. Quart. J. Roy. Meteor. Soc., 128, 647–677, doi:10.1256/003590002321042135.

    • Search Google Scholar
    • Export Citation

  • Skamarock, W. C., and Coauthors, 2008: A description of the Advanced Research WRF version 3. NCAR Tech. Note NCAR/TN-475+STR, 113 pp. [Available online at http://www.mmm.ucar.edu/wrf/users/docs/arw_v3_bw.pdf.]

  • Smith, E. K., and S. Weintraub, 1953: The constants in the equation for the atmospheric refractive index at radio frequencies. Proc. IRE, 41, 1035–1037, doi:10.1109/JRPROC.1953.274297.

    • 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 radio occultation data: Case simulations with a high-resolution weather model. Mon. Wea. Rev., 133, 2200–2212, doi:10.1175/MWR2948.1.

    • 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, doi:10.1175/MWR3006.1.

    • Search Google Scholar
    • Export Citation

  • Syndergaard, S., E. R. Kursinski, B. M. Herman, E. M. Lane, and D. E. Flittner, 2005: A refractive index mapping operator for assimilation of occultation data. Mon. Wea. Rev., 133, 2650–2668, doi:10.1175/MWR3001.1.

    • Search Google Scholar
    • Export Citation

  • Turner, J., and Coauthors, 2005: Antarctic climate change during the last 50 years. Int. J. Climatol., 25, 279–294, doi:10.1002/joc.1130.

    • Search Google Scholar
    • Export Citation

  • Uotila, P., T. Vihma, A. Pezza, I. Simmonds, K. Keay, and A. Lynch, 2011: Relationships between Antarctic cyclones and surface conditions as derived from high-resolution numerical weather prediction data. J. Geophys. Res., 116, D07109, doi:10.1029/2010JD015358.

    • Search Google Scholar
    • Export Citation

  • Vinnikov, K. Y., and N. C. Grody, 2003: Global warming trend of mean tropospheric temperature observed by satellites. Science, 302, 269–272, doi:10.1126/science.1087910.

    • Search Google Scholar
    • Export Citation

  • Wang, X., D. M. Barker, C. Snyder, and T. M. Hamill, 2008a: A hybrid ETKF–3DVAR data assimilation scheme for the WRF Model. Part I: Observing system simulation experiment. Mon. Wea. Rev., 136, 5116–5131, doi:10.1175/2008MWR2444.1.

    • Search Google Scholar
    • Export Citation

  • Wang, X., D. M. Barker, C. Snyder, and T. M. Hamill, 2008b: A hybrid ETKF–3DVAR data assimilation scheme for the WRF Model. Part II: Real observation experiments. Mon. Wea. Rev., 136, 5132–5147, doi:10.1175/2008MWR2445.1.

    • Search Google Scholar
    • Export Citation

  • Wee, T.-K., and Y.-H. Kuo, 2004: Impact of a digital filter as a weak constraint in MM5 4DVAR: An observing system simulation experiment. Mon. Wea. Rev., 132, 543–559, doi:10.1175/1520-0493(2004)132<0543:IOADFA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Wee, T.-K., Y.-H. Kuo, D. H. Bromwich, and A. J. Monaghan, 2008: Assimilation of GPS radio occultation refractivity data from CHAMP and SAC-C missions over high southern latitudes with MM5 4DVAR. Mon. Wea. Rev., 136, 2923–2944, doi:10.1175/2007MWR1925.1.

    • Search Google Scholar
    • Export Citation

  • Wee, T.-K., Y.-H. Kuo, and D.-K. Lee, 2010: Development of a curved ray tracing method for modeling of phase paths from GPS radio occultation: A two-dimensional study. J. Geophys. Res., 115, D24119, doi:10.1029/2010JD014419.

    • Search Google Scholar
    • Export Citation

  • Wee, T.-K., Y.-H. Kuo, D.-K. Lee, Z. Liu, W. Wang, and S.-Y. Chen, 2012: Two overlooked biases of the advanced research WRF (ARW) Model in geopotential height and temperature. Mon. Wea. Rev., 140, 3907–3918, doi:10.1175/MWR-D-12-00045.1.

    • Search Google Scholar
    • Export Citation

  • Wickert, J., T. Schmidt, G. Beyerle, R. König, C. Reigber, and N. Jakowski, 2004: The radio occultation experiment aboard CHAMP: Operational data analysis and validation of vertical atmospheric profiles. J. Meteor. Soc. Japan, 82, 381–395, doi:10.2151/jmsj.2004.381.

    • Search Google Scholar
    • Export Citation

  • Yang, S.-C., S.-H. Chen, S.-Y. Chen, C.-Y. Huang, and C.-S. Chen, 2014: Evaluating the impact of the COSMIC RO bending angle data on predicting the heavy precipitation episode on 16 June 2008 during SoWMEX- IOP8. Mon. Wea. Rev., in press.

    • Search Google Scholar
    • Export Citation
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