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Hui Liu

Project Scientist II
Data Assimilation Research Section (DAReS)
Institute for Mathematics Applied to Geosciences (IMAGe)
National Center for Atmospheric Research (NCAR)
Boulder, COLORADO, 80307
hliu@ucar.edu, 303.497.1304 (work), 303.497.1298 (fax)

Research Interests:

1. Use of advanced satellite observations to improve track and intensity forecast of tropical cyclones.

2. Application of ensemble-based data assimilation systems for meso-scale high impact weather forecast, such as tropical cyclones.

3. Application of satellite observations in analysis and forecast of Monsoon system through advanced data assimilation methods.

4. Retrival of tropical water vapor from radio occultation and other IR/WM measurements.


Recent Journal Publications

Li Jun and Hui Liu, 2009:
Improved Hurricane Track and Intensity Forecast Using Single Field-of-View Advanced IR Sounding Measurements, Geophysical Research Letters, 2009, Vol.36, No. 6, L11813, doi:10.1029/2009GL038285. [pdf]

Kuo Ying-Hwa, Hui Liu, Yong-Run Guo, Chuen-Teyr Terng, and Yun-Tien 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, Editors: K.N. Liou, M.D. Chou, and H.H. Hsu, World Scientific Press, pp.458-483, 2009.

Liu H., J. L. Anderson, Y.-H. Kuo, and Y. Chen, 2009:
Benefits of radio occultation observations to analyses and forecast of tropical cyclone genesis (revising for Mon. Wea. Rev.).

R. A. Anthes, P. A. Bernhardt, Y. Chen, L. Cucurull, K. F. Dymond, D. Ector, S. Healy, S.-P. Ho, D. C. Hunt, Y.-H. Kuo, H. Liu, K. Manning, C. McCormick, T. K. Meehan, W. J. Randel, C. Rocken, W. Schreiner, S. V. Sokolovskiy, S. Syndergaard, D. C. Thompson, K. E. Trenberth, T.-K. Wee, N. L. Yen, and Z. Zeng, 2008:
The COSMIC/FORMOSAT-3 Mission: Early Results, Bull. Amer. Meteor. Soci., v89, No.3, 313-333.

2009GL038285-Hurricane_JunLi.pdf
Liu H., J. L. Anderson, Y.-H. Kuo, C. Snyder, and A Caya, 2008:
Evaluation of a non-local observation operator in assimilation of CHAMP radio occultation refractivity with WRF, Mon. Wea. Rev., Vol. 136, No.1, 242-256. [pdf]

Liu H., J. L. Anderson, Y.-H. Kuo, and K. Raeder, 2007:
Importance of forecast error multivariate correlations in idealized assimilation of GPS radio occultation data with the Ensemble Adjustment filter, Mon. Wea. Rev., Vol. 135, No.1, 173-185. [pdf]

Zou X., Liu H., R.A. Anthes, H. Shao, J.C. Chang, and Y.J. Zhu, 2004:
Impact of CHAMP radio occultation observation on global analyses and forecasts in the absence of AMSU radiance data, Special issue of J. of Meteor. Soc. of Japan, 82, No.1B, 533-549.

Liu H. and X. Zou, 2003:
Improvements to a GPS radio occultation ray-tracing model and their impacts on assimilation of bending angle, J. Geophys. Res., 108, D17, 4548, doi:10.1029/2002JD003160. [pdf]

Zou, X., H. Liu, and R. Anthes, 2002:
A statistical estimate of errors in the calculation of radio occultation bending angles caused by a 2D approximation of ray-tracing and the assumption of spherical symmetry of the atmosphere, J. of Atmos. and Oceanic tech., 19: (1) 51-64.

Liu Hui, Zou X., Shao H., R. Anthes, J. Chang, J. Tseng and B. Wang, 2001:
Impact of 837 GPS/MET bending angle profiles on assimilation and forecasts for the period June 20-30, 1995, J. Geophys. Res., 106: (D23) 31771-31786.

Liu H. and X. Zou, 2001:
The impact of NORPEX targeted dropsondes on the Analyses and 2-3 day forecasts of a landing Pacific winter storm using NCEP 3D-Var and 4D-var systems, Mon. Wea. Rev., 129: 1987-2004.

Zou X., H. Liu, J. Derber, J. Sela, R. Treadon, I. Navon, and B. Wang, 2001:
Four-dimensional variational data assimilation with a diabatic version of the NCEP spectral model: System development and preliminary results, Quart. J. of Royal Meteorological Society, 127: 1095-1122.

Zou X., B. Wang, H. Liu, R. Anthes, T. Matsumura, and Y. Zhu, 2000:
Use of GPS/MET refraction angles in 3D variational analysis, Quart. J. Royal Meteorological Society, 126: 1-28.


Recent Presentations

Initialization of the Environment of Tropical Cyclogenesis by Assimilating RO Data using an Ensemble Filter, COSMIC User Workshop, October 27-29, 2009, Boulder, CO.

Improve hurricane forecast using hyper-spectral IR soundings, CIMSS, Madison, Wisconsin, June 18-19, 2009.

Improve track and intensity forecast of hurricane using satellite measurements, COMET/UCAR Workshop of 6th annual Satellite Curriculum Development, Boulder, May 11-13, 2009.

Application of Radio Occultation Data in Forecast of Tropical Cyclones Using WRF Ensemble Assimilation System, National Taiwan University, Taipei, April 16, 2009.

Application of Radio Occultation Data in Forecast of Tropical Cyclones Using WRF Ensemble Assimilation System, Taiwan Central Weather Beaureu, Taipei, April 13, 2009.

Overview of NCAR Universal Ensemble Data Assimilation System (DART), Taiwan Central Weather Beaureu, Taipei, April 15, 2009.

Impact of radio occultation observations on ensemble analyses and forecasts of tropical cyclones, 2009 AMS Annual meeting, Phoenix, AZ, January 11-15, 2009.

Application of Radio Occultation Data in Analyses and Forecasts of Tropical Cyclones Using an Ensemble Assimilation System, 2008 Joint Statistical Meeting, Denver, August 6, 2008.

Improving Forecasts of Asian Monsoon Rainfall Using COSMIC Radio Occultation Refractivity Observations, 28th Conference on Hurricanes and Tropical Meteorology 28 April - 2 May 2008, Orlando, FL.

The Impacts of Radio Occultation Data on analyses and prediction of the Monsoon and hurricanes using WRF ensemble forecast system, SPIE, San Diego, California, August, 26-28, 2007.

The Impacts of COSMIC Radio Occultation Data on prediction of Monsoon rainfall, IUGG 2007, Perugia, Italy, July 2-13, 2007.

Application of GPS radio occultation data in improving regional analyses of water vapor and temperature over tropical oceans, China National Climate Center, Beijing, 28 December, 2006.

Influence of COSMIC Satellite data in improving analyses over tropical oceans, 2006 AGU Fall meeting, San Francisco, CA, 11-15 December, 2006.

Application of GPS radio occultation refractivity in improving tropical analyses of tempeature and water vapor, First FORMSAT-3/COSMIC User Data Workshop, Boulder, CO, 16-18 October, 2006.

Assimilations of Global Positioning System radio occultation observations with an Ensemble filter in Atmospheric Prediction Models, 2006 IEEE International Geoscience and Remote Sensing Symposium, Denver, CO, 31 July - 4 August, 2006.

Exploring application of GPS RO data in improving analyses of T and Q in radiosonde sparse regions using WRF ensemble data assimilation system, 7th WRF User Workshop, Boulder, CO, 19-22 June, 2006.

Exploring application of Radio Occultation measurements in Improving Analyses in traditional data sparse regions with WRF/DART ensemble data assimilation system, 2nd Ensemble Data Assimilation Workshop, 10-12, April, 2006, Austin, Texas.

Preliminary results from assimilation of GPS RO data in WRF using an ensemble filter, NCAR MMM seminar, Dec 19, 2005, Boulder, Colorado

Exploring impacts of multivariate forecast error covariances in RO data assimilation in the lower troposphere, Second GPS RO Data Users Workshop, 22-24 August, 2005, Lansdowne, Virginia.

Use of RO refractivity in NCAR ensemble filter assimilation system, NCAR 2004 Summer Colloquium: Atmospheric Remote Sensing using the GPS, July 1-2, 2004, Boulder, Colorado.

Preliminary results on variational assimilation of GPS bending angles using a ray-tracing operator, NASA/GSFC, Greenbelt, Maryland, Dec. 2-4, 2002.

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Last modified: Friday, 20-Nov-2009 14:12:31 MST