"Everything should be made as simple as possible, but not simpler." - Albert Einstein

Seminar Announcement

Emulating and Calibrating the Lyon-Fedder-Mobarry Magnetosphere-Ionosphere Coupled Computer Model using Predictive Processes

Matt Heaton, The National Center for Atmospheric Research post-doc

Monday, March 26, 2012

4:00 p.m., room 237, Weber Bldg


The Lyon-Fedder-Mobarry global magnetosphere-ionosphere coupled (LFM- MIX) model is a multiple fidelity computer model used to study sun-earth interactions bysimulating geomagnetic storms. Higher fidelities of the LFM-MIX model require more computation but, ultimately, more accurately capture the governing physical processes under study. Given a set of input values and solar wind data, the LFM-MIX model numerically solves the magnetohydrodynamic equations and outputs a spatio-temporal field of onospheric energy. This work focuses on relating the output from the LFM-MIX model run at different fidelities to field observations of ionospheric energy. Of particular interest here are the input settings (and their uncertainties) for the LFM-MIX model such that output most closely matches the field observations. To estimate these input settings, a low rank spatio-temporal statistical LFM- MIX model emulator is constructed using predictive processes. The statistical emulator links the multiple fidelities of the LFM-MIX model to achieve calibration of the input variables to field observations. In this way, the less computationally demanding yet lower fidelity LFM-MIX model is leveraged to provide estimates of the higher fidelity LFM-MIX model output. The higher fidelity LFM-MIX output is then, in turn, used for calibration of the input parameters.