Exact nonlinear filtering of geophysical systems

Hristo Chipilski

National Center for Atmospheric Research, Advanced Study Program

Tuesday, March 28, 2023, 2:00 pm


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Or by Phone: (US)+1 571-317-3129 | Access Code: 343-392-437
NOTE: If COVID-19 Community Level is LOW, DSRC Staff may attend in person (Room 2A305). Masks encouraged.


This seminar will discuss the application and development of data assimilation (DA) methods for the estimation of nonlinear geophysical systems. I will first present systematic experiments which demonstrate the positive impact of assimilating ground-based remote sensors for improving the forecasts of organized night-time convection. However, comparison between single profiler experiments will reveal how standard (Gaussian-based) DA methods lead to inconsistent analysis results. This finding will then serve as a motivation for the second part of my talk where I will combine traditional DA methods and powerful AI/ML techniques to derive an exact nonlinear filtering theory. Specifically, I will describe and exemplify an ensemble-based DA algorithm which leverages the special mathematical properties of invertible neural networks to generalize the celebrated ensemble Kalman filter.

Seminar Contact: psl.seminars@noaa.gov