Dr. Istvan Szunyogh

Research Interests

• Numerical weather prediction
• Ensemble forecasting
• Data assimilation
• Dynamical systems
• Predictability of geophysical fluid dynamical systems

Current Projects

• Assessing atmospheric predictability with a global analysis-forecast system
• Development of an ensemble Kalman filter data assimilation system for Martian weather analysis and forecasting (This research in the News)
• Tropical cyclone ensemble data assimilation
• Statistical covariance estimation in data assimilation and its applications to Earth Science problems 

Experience

•  Associate Professor, February 2009-Present; Department of Atmospheric Sciences, Texas A&M University
• Associate Research Scientist, July 2005–January 2009; Institute for Physical Science and Technology and Department of Atmospheric and Oceanic Science (formerly Department of Meteorology), Member of the Applied Mathematics and Scientific Computation Graduate Program and the Burgers Program for Fluid Dynamics, University of Maryland
• Assistant Research Scientist, February 2001–June 2005; Institute for Physical Science and Technology and Department of Meteorology, University of Maryland
• Visiting Scientist, September 1997–February 2001; University Corporation for Atmospheric Research (UCAR), based at the Environmental Modeling Center, National Centers for Environmental Prediction (formerly NMC), National Weather Service 
• Postdoctoral Associate, March 1997–September 1997; Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts, based at NCEP
• Postdoctoral Visiting Scientist, September 1996–February 1997; Mesoscale and Microscale Meteorology Division, National Center for Atmospheric Research, Boulder, Colorado, based at NCEP
• Visiting Scientist at the Program “Mathematics of the Atmosphere and Ocean Dynamics” (July 1996-September 1996), Isaac Newton Institute for Mathematical Sciences, Cambridge, United Kingdom
• Magyary Zoltan Postdoctoral Fellow, September 1995–August 1996; Department of Meteorology, E¨otv¨os Lorand University, Budapest, Hungary
• Research Scientist, September 1998–September 1999 (on leave); Department of Meteorology, Eotvos Lorand University, Budapest, Hungary
• Research Associate, September 1991–September 1998 (on leave after September 1995), Department of Meteorology, Eotvos Lorand University, Budapest, Hungary

Publications

 * indicates a student and ** indicates a postdoctoral associate, whose research was advised or co-advised by I. S.

Most Recent Publications

• Yoon, Y.-N., E. Ott, I. Szunyogh, 2010: On the propagation of information and the use of localization in ensemble Kalman filtering. Submitted to J. Atmos. Sci.
• Hoffman*, M. J., S. J. Greybush*, R. J. Wilson, G. Gyarmati, R. N. Hoffman, K. Ide, E. Kostelich, T. Miyoshi, I. Szunyogh, E. Kalnay, 2010: An ensemble Kalman filter data assimilation system for the Martian atmosphere: Implementation and simulation experiments. Submitted to Icarus.
• Aravequia**, J. A., I. Szunyogh, E. J. Fertig, E. Kalnay, D. Kuhl, and E. J. Kostelich, 2009: Evaluation of a strategy for the assimilation of satellite radiance observations with the Local Ensemble Kalman Filter. Submitted to Mon. Wea. Rev.
• Satterfield*, E.  and I. Szunyogh, 2009: Predictability of the performance of an ensemble forecast system: Predictability of the space of uncertainties. Mon. Wea. Rev. (in press).
• J. Liu*, H. Li, E. Kalnay, I. Szunyogh, and E. J. Kostelich, 2009: Univariate and multivariate assimilation of AIRS humidity retrievals with the Local Ensemble Transform Kalman Filter. Mon. Wea. Rev., 137, 3918-3932.
• S.-J. Baek**, I. Szunyogh, B. R. Hunt, and E. Ott, 2009: Correcting for surface pressure background bias in ensemble-based analyses. Mon. Wea. Rev., 137, 2349-2364.
• Fertig*, E. J., S.-J. Baek*, B. R. Hunt, E. Ott, I. Szunyogh, J. A. Aravequia, E. Kalnay, H. Li*, and J. Liu*, 2009: Observation bias correction with an Ensemble Kalman Filter. Tellus,  61A, 210-226.
• Sellwood*, K. J., S. J. Majumdar, B. E. Mapes, and I. Szunyogh, 2008: Predicting the influence of observations on medium-range winter weather forecasts. Q. J. Roy. Met. Soc., 134, 2011-2027.
• Hoffman, R. N., R. M. Ponte, E. Kostelich, A. Blumberg, I. Szunyogh, S. Vinogradov, and J. M. Henderson, 2008: Data Assimilation in New York Harbor: A simulation study applying a Local Ensemble Kalman Filter to the Estuarine and Coastal Ocean Model. J. Atmos. and Ocean. Tech., 25, 1638-1656.
• Szunyogh, I., E. J. Kostelich, G. Gyarmati, E. Kalnay, B. R. Hunt, E. Ott, E. Satterfield*, and J. A. Yorke, 2008: A Local Ensemble Transform Kalman Filter data assimilation system for the NCEP global model. Tellus, 60A, 113-130.
   

Other Selected Publications

• Hunt, B. R., E. J. Kostelich, and I. Szunyogh, 2007: Efficient data assimilation for spatiotemporal chaos: a Local Ensemble Transform Kalman Filter. Physica D, 230, 112-126.
• Kuhl*, D., I. Szunyogh, E. Kostelich, G. Gyarmati, E. Kalnay, B. R. Hunt, E. Ott, J. A. Yorke, 2007: Assessing predictability with a Local Ensemble Kalman Filter. J. Atmos. Sci.,64, 1116-1140.
• Baek*, S.-J., B. R. Hunt, I. Szunyogh, and E. Ott, 2006: Local ensemble Kalman filtering in the presence of model bias. Tellus, 58A, 293-306.
• Szunyogh I., E. J. Kostelich, G. Gyarmati, D. J. Patil, B. R. Hunt, E. Kalnay, E. Ott, and J. A. Yorke, 2005: Assessing a local ensemble Kalman filter: Perfect model experiments with the NCEP global model. Tellus, 57A, 528-545.
• Oczkowski*, M., I. Szunyogh, and D. J. Patil, 2005: Mechanisms for the development of locally low dimensional atmospheric dynamics. J. Atmos. Sci.,65, 1135-1156.
• Ott, E., B. R. Hunt, I. Szunyogh, A. V. Zimin*, E. J. Kostelich, M. Corazza*, E. Kalnay, D. J. Patil, and J. A. Yorke, 2004: A local ensemble Kalman filter for atmospheric data assimilation. Tellus,56A, 415-428.
• Zimin*, A. V., I. Szunyogh, D. J. Patil, B. R. Hunt, and E. Ott, 2003: Extracting envelopes of Rossby wave packets. Mon. Wea. Rev., 131, 1011-1017.
• Szunyogh, I., Z. Toth, A. V. Zimin*, S. Ma jumdar, and. A Persson, 2002: Propagation of the effect of targeted weather observations: The 2000 Winter Storm Reconnaissance program. Mon. Wea. Rev.,130, 1144-1165.
• Szunyogh, I, and Z. Toth, 2002: The effect of increased horizontal resolution on the NCEP global ensemble mean forecasts. Mon. Wea. Rev.,130, 1125-1143.
• Szunyogh, I., Z. Toth, R. E. Morss, S. J. Ma jumdar, B. J. Etherton, and C. H. Bishop, 2000: The effect of targeted dropsonde observations during the 1999 Winter Storm Reconnaissance program. Mon. Wea. Rev.,128, 3520-3537.
• Szunyogh, I., Z. Toth, K. A. Emanuel, C. H. Bishop, C. Snyder, J. Woolen, T. Marchok, and R. Morss, 1999: Ensemble-based targeting experiments during FASTEX: The impact of dropsonde data from the Lear jet. Quart. J. Roy. Met. Soc., 125, 3520-3537.
• McLachlan, R. I., I. Szunyogh, and V. Zeitlin, 1997: Hamiltonian finite-dimensional models of baroclinic instability. Phys. Let. A,229, 299-305.
• Szunyogh I., E. Kalnay, and Z. Toth, 1997: A comparison of Lyapunov and optimal vectors in a low-resolution GCM. Tellus, 49A, 200-227.
• Szunyogh I., 1993: Finite-dimensional quasi-Hamiltonian structure in simple model equations. Meteorology and Atmospheric Physics,52, 49-57.