Prior to joining the faculty at UMD, I spent more than a decade at NOAA/National Centers for Environmental Prediction/Environmental Modeling Center working as a member of the data assimilation team in the global weather and climate modeling branch.
My primary interest is in the use of data assimilation to improve numerical weather prediction, most recently through the use of the hybrid EnVar algorithm for the NCEP Global Forecast System model. My research group is also exploring ways to improve the initialization of tropical cyclones. I am also interested in atmospheric predictability, ensemble forecasting methods, and numerical modeling.
More generally, I am interested in a wide variety of atmospheric phenomenon including mid-latitude cyclones, tropical cyclones, and severe weather.
My primary teaching responsibility is Synoptic Meteorology (AOSC 470/600).
Data assimilation is used for state estimation by combining observations with numerical models of a physical system. My main area of interest is in algorithm development aimed at improving initial conditions for numerical weather prediction. As part of my PhD thesis as well as my efforts at NCEP/EMC, I worked on developing and testing a hybrid ensemble-variational (EnVar) algorithm for use with the operational global data assimilation system and global forecast system model. Recently, work has been focused on extending this to four dimensions, i.e. 4DEnVar: a unique 4D variational-based method that does not require a tangent linear or adjoint model.
Image from Lahoz, W. A., and P. Schneider, Data Assimilation: Making Sense of Earth Observation, Frontiers in Environmental Science
B.S. Atmospheric and Oceanic Sciences, University of Wisconsin-Madison
M.S. Atmospheric and Oceanic Sciences, University of Wisconsin-Madison
Ph.D. Atmospheric and Oceanic Science, University of Maryland-College Park
Donald Lippi - Radar assimilation for high resolution NWP
Greg Porter - Case study of Ellicott City flooding event
Chu-Chun Chang - Tropical cyclone initialization for operational NWP
Patricia Fricke - Advanced data assimilation for PWS operational global NWP system
Kanishk Gohil - Tropical cyclone initialization for operational NWP
Dylan Jeffrey - TBD
Troy Arcomano - Quantitative and qualitative evaluation of TerpWRF
External Graduate Student
Deng-Shun Chen (National Central University, Taiwan) - Scale-dependent weighting and localization for EnVar data assimilation
Image courtesy of http://www.physicalgeography.net/
Numerical Model Graphics