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  • Data for Global Ionosphere Thermosphere Model Simulations with MSIS and WACCM-X boundary conditions

    work
    Creator:
    Malhotra, Garima and Ridley, Aaron
    Description:
    This research aims to understand the importance of lower thermospheric atomic oxygen on the upper thermosphere. O number densities between 95-100 km from WACCM-X are much closer to the observations from SABER instrument on TIMED satellite as compared to those from MSIS. We show in this study that the correction of the lower boundary atomic oxygen yields better agreement between GITM and GUVI O/N2 in the upper thermosphere .
    Keyword:
    Lower Thermosphere Atomic Oxygen, Thermospheric Dynamics, Thermospheric composition and mixing, Lower-Upper Thermosphere Vertical Coupling, GITM - WACCMX coupling, and Global Ionosphere Thermosphere Model
    Citation to related publication:
    Malhotra, G., Ridley, A. J., Marsh, D. R., Wu, C., Paxton, L. J., & Mlynczak, M. G. (2020). Impacts of Lower Thermospheric Atomic Oxygen on Thermospheric Dynamics and Composition Using the Global Ionosphere Thermosphere Model. Journal of Geophysical Research: Space Physics, e2020JA027877.  https://doi.org/10.1029/2020JA027877
    Discipline:
    Science

  • A Microscopic Theory of Entropic Bonding – Energy/Simulation Scripts with Representative Data

    work
    Creator:
    Vo, Thi and Glotzer, Sharon C.
    Description:
    The goal of this project is to develop a first principle driven approach for predicting the self-assembly behavior of entropically driven crystallization. We first developed a set of mean-field theoretical framework that captures the relevant energetic contributions to the assembly process and then evaluate relevant terms within our framework to determine the excess free energy of formation for each lattice (matlab/octave codes). We then validate theoretical predictions of relevant features like shape and bonding orbitals using standard MD simulations using HOOMD-Blue (simulation scripts). and This research was supported by the Office of the Undersecretary of Defense for Research and Engineering (OUSD(R&E)), Newton Award for Transformative Ideas during the COVID-19 Pandemic, Award number HQ00342010030.
    Keyword:
    Self-Assembly, Entropy, Thermodynamics, Simulations, and Theory
    Citation to related publication:
    Vo, T., & Glotzer, S. C. (2021). Microscopic Theory of Entropic Bonding for Colloidal Crystal Prediction. ArXiv:2107.02081 [Cond-Mat].  http://arxiv.org/abs/2107.02081
    Discipline:
    Science

  • Space Weather Modeling Framework simulations of ground magnetometer data

    work
    Creator:
    Al Shidi, Q. and Pulkkinen, T.
    Description:
    Provided are the resultant and processed data.
    Keyword:
    space physics, ground magnetometers, magnetosphere, numerical space physics, solar wind, numerical space physics, and ionosphere
    Discipline:
    Science

  • Results for "New Findings from Explainable SYM-H Forecasting using Gradient Boosting Machines"

    work
    Creator:
    Iong, Daniel, Chen, Yang, Toth, Gabor, Zou, Shasha, Pulkkinen, Tuija I., Ren, Jiaen, Camporeale, Enrico, and Gombosi, Tamas I. I.
    Description:
    In this work, we trained gradient boosted trees using XGBoost to predict the SYM-H forecasting using different combinations of solar wind and interplanetary magnetic field (IMF) parameters. Data are in csv and Python pickle formats.
    Keyword:
    SYM-H forecasting
    Citation to related publication:
    Iong, D., Y. Chen, G. Toth, S. Zou, T. I. Pulkkinen, J. Ren, E. Camporeale, and T. I. Gombosi, New Findings from Explainable SYM-H Forecasting using Gradient Boosting Machines, Space Weather,11, accepted, 2022.  https://doi.org/10.1002/essoar.10508063.3
    Discipline:
    Science

  • Dataset Containing Global Modeling Results Comparing Magnetopause Distances and CPCP

    work
    Creator:
    Agnit Mukhopadhyay
    Description:
    Conducting quantitative metrics-based performance analysis of first-principles-based global magnetosphere models is an essential step in understanding their capabilities and limitations, and providing scope for improvements in order to enhance their space weather prediction capabilities for a range of solar conditions. In this study, a detailed comparison of the performance of three global magnetohydrodynamic (MHD) models in predicting the Earth’s magnetopause location and ionospheric cross polar cap potential (CPCP) has been presented. Using the Community Coordinated Modeling Center’s Run-on-Request system and extensive database on results from various magnetospheric scenarios simulated for a variety of solar wind conditions, the aforementioned model predictions have been compared for magnetopause standoff distance estimations obtained from six empirical models, and with cross polar cap potential estimations obtained from the Assimmilative Mapping of Ionospheric Electrodynamics (AMIE) Model and the Super Dual Auroral Radar Network (SuperDARN) observations. We have considered a range of events spanning different space weather activity to analyze the performance of these models. Using a fit performance metric analysis for each event, we have quantified the models’ reproducibility of magnetopause standoff distances and CPCP against empirically-predicted observations, and identified salient features that govern the performance characteristics of the modeled magnetospheric and ionospheric quantities.
    Citation to related publication:
    Mukhopadhyay, A., Jia, X., Welling, D. T., & Liemohn, M. W. (2021). Global Magnetohydrodynamic Simulations: Performance Quantification of Magnetopause Distances and Convection Potential Predictions. Frontiers in Astronomy and Space Sciences, 8.  https://doi.org/10.3389/fspas.2021.637197
    Discipline:
    Engineering and Science

  • MHD-AEPIC simulation data of the geomagnetic storm event

    work
    Creator:
    Xiantong Wang
    Description:
    We perform a geomagnetic event simulation using a newly developed magnetohydrodynamic with adaptively embedded particle-in-cell (MHD-AEPIC) model. We have developed effective criteria to identify reconnection sites in the magnetotail and cover them with the PIC model. The MHD-AEPIC simulation results are compared with Hall MHD and ideal MHD simulations to study the impacts of kinetic reconnection at multiple physical scales. At the global scale, the three models produce very similar SYM-H and SuperMag Electrojet (SME) indexes, which indicates that the global magnetic field configurations from the three models are very close to each other. At the mesoscale we compare the simulations with in situ Geotail observations in the tail. All three models produce reasonable agreement with the Geotail observations. The MHD-AEPIC and Hall MHD models produce tailward and earthward propagating fluxropes, while the ideal MHD simulation does not generate flux ropes in the near-earth current sheet. At the kinetic scales, the MHD-AEPIC simulation can produce a crescent shape distribution of the electron velocity space at the electron diffusion region which agrees very well with MMS observations near a tail reconnection site. These electron scale kinetic features are not available in either the Hall MHD or ideal MHD models. Overall, the MHD-AEPIC model compares well with observations at all scales, it works robustly, and the computational cost is acceptable due to the adaptive adjustment of the PIC domain.
    Keyword:
    MHD, PIC, and Magnetosphere
    Discipline:
    Science

  • Anthropogenic Aerosol indirect effects in cirrus clouds

    work
    Creator:
    Penner, Joyce E., Zhou, Cheng, Garnier, Anne, and Mitchell, David
    Description:
    This data set contains the scripts and data sets needed to create the 9 figures in the referenced publication.
    Keyword:
    Anthropogenic Aerosol indirect effects, cirrus clouds, and ice nucleation
    Citation to related publication:
    Penner, J. E., Zhou, C., Garnier, A., & Mitchell, D. L. (2018). Anthropogenic aerosol indirect effects in cirrus clouds. Journal of Geophysical Research: Atmospheres,123, 11,652–11,677.  https://doi.org/10.1029/2018JD029204
    Discipline:
    Science

  • Space Weather Modeling Framework (SWMF) Simulation of Sep 7 2017 Geomagnetic Storm

    work
    Creator:
    Wang, Zihan
    Description:
    SWMF is used to study the segmentation of SED plume into polar cap patches during the geomagnetic storm on Sep 7, 2017. The database includes the 3D output in the upper atmosphere from GITM, the 2D output from Ionospheric Electrodynamics (IE) and 3D output from BATSRUS. The output from GITM can be read with thermo_batch_new.pro. The output from IE can be opened with Spacepy at  https://pythonhosted.org/SpacePy/. The output from BATSRUS can be opened with tecplot. More details can be found in Readme.txt.
    Keyword:
    MHD and Ionosphere
    Citation to related publication:
    Wang, Z., Zou, S., Coppeans, T., Ren, J., Ridley, A., & Gombosi, T. (2019). Segmentation of SED by Boundary Flows Associated With Westward Drifting Partial Ring current. Geophysical Research Letters, 46(14), 7920–7928.  https://doi.org/10.1029/2019GL084041
    Discipline:
    Science