| Physics Department Seminar | University of Alaska Fairbanks | 
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| J O U R N A L C L U B | 
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                Uncertainty
                quantification of the ionosphere-thermosphere conditions
                associated with the solar wind  | 
        
| by | 
| Weijia Zhan | 
| University of Colorado Boulder | 
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             ABSTRACT Information
                of the  uncertainty in the ionosphere-thermosphere (IT)
              system is important to make probabilistic predictions of space
              weather events (i.e., equatorial ionospheric irregularities),
              satellite or debris obits (i.e, neutral density and atmospheric
              drag), and impacts on HF communications (i.e., HmF2). In this
              study, we apply uncertainty quantification (UQ) methods to
              quantify the variability of the IT conditions associated with the
              uncertainty of the solar wind by using the whole atmosphere model
              with ionosphere-plasmasphere dynamics (WAM-IPE) model. To apply
              the UQ method and conduct sensitivity analysis, historical
              measurements of solar wind velocity, density, and interplanetary
              magnetic field (IMF) Bz are fed into a neutral network
              (variational autoencoder, VAE) to reduce the dimensions of input
              parameters and generate new solar wind samples to drive WAM-IPE.
              Polynomial chaos expansion (PCE) is then applied to quantify the
              uncertainty of the quantities of interest (QoIs) from the outputs
              of WAM-IPE. Electron densities, plasma drifts, and neutral winds
              from 6 magnetic equatorial and low latitude locations are selected
              as QoIs. The uncertainties of these QoIs will be compared with
              previous observations and numerical simulations. Sensitivity
              analysis will be conducted to identify the drivers that contribute
              the most to the uncertainty of the QoIs.  | 
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            Friday, 18 November 2022  | 
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| Only on Zoom : https://alaska.zoom.us/j/88028763203?pwd=cmxjNVA0aGFmdTBONUJyUERDOXF2Zz09 | |||
| 3:45PM |