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- Creator:
- Valeriy Tenishev
- Description:
- This data represents examples of some applications of AMPS and illustrates the potential of the code for modeling various physical phenomena.
- Keyword:
- Monte Carlo, DSMC
- Citation to related publication:
- Tenishev, V., Shou, Y., Borovikov, D., Lee, Y., Fougere, N., Michael, A., & Combi, M. R. (2021). Application of the Monte Carlo Method in Modeling Dusty Gas, Dust in Plasma, and Energetic Ions in Planetary, Magnetospheric, and Heliospheric Environments. Journal of Geophysical Research: Space Physics, 126(2), e2020JA028242. https://doi.org/10.1029/2020JA028242
- Discipline:
- Science
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Division of Fishes
User Collection- Creator:
- University of Michigan Museum of Zoology
- Description:
- Division of Fishes
- Discipline:
- Science
48Works -
- 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
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- Creator:
- McCuen, Brett A.
- Description:
- These data are TLA events identified in MACCS magnetometer data throughout 2015. These events are short-timescale (< 60 s), large -amplitude (> 6 nT/s) magnetic disturbances measured at Earth's surface that are analyzed for space weather research purposes. and The events were identified in a year's worth of magnetic field data using an algorithm developed in the MATLAB platform. The algorithm dBdt_main.m can be run using the associated scripts (clean_maccs.m, simple_dbdt.m, extremes1.m, newdbdt.m) to return the events in the 2015_AllEvents.csv file. The substorm onset delays of each event are determined with the onset_delays.m script and the substorm event list 20191127-15-56-substorms.csv (both included).
- Keyword:
- space weather impacts, geomagnetically induced currents, GIC, transient induced currents, transient large amplitude, dB/dt search algorithm, and TLA
- Citation to related publication:
- Engebretson, M. J., Pilipenko, V. A., Ahmed, L. Y., Posch, J. L., Steinmetz, E. S., Moldwin, M. B., … Vorobev, A. V. (2019). Nighttime Magnetic Perturbation Events Observed in Arctic Canada: 1. Survey and Statistical Analysis. Journal of Geophysical Research: Space Physics, 124(9), 7442–7458. https://doi.org/10.1029/2019JA026794
- Discipline:
- Science
-
Profiles of near-surface rock mass strength across gradients in erosion, burial, and time [Data set]
- Creator:
- Townsend, Kirk F, Clark, Marin K, and Zekkos, Dimitrios
- Description:
- These datasets support the findings of Townsend et al. (2020). In this article, we project profiles of rock mass shear strength into the shallow subsurface (~30 m depth) using the Hoek and Brown criterion with Geological Strength Index (GSI) observations of outcrop structure and surface conditions, and Schmidt hammer rebound values of intact (unfractured) rock hardness. We compare these projected rock mass shear strength profiles to shear-wave velocity profiles collected using shallow geophysical arrays. We evaluate our methods in the Western Transverse Ranges of southern California, which exhibit strong gradients in the depth of latest-Mesozoic through Cenozoic sedimentary rocks exposed at the surface today, and in erosion rates quantified from catchment-average cosmogenic radionuclide concentrations and low-temperature apatite and zircon (U-Th)/He thermochronometry. We find that stratigraphic age and burial depth exerts the strongest apparent control on rock strength and S-wave velocities, likely due to diagenetic changes associated with burial. For rocks of the same age and inferred burial history, we observe that shear strength and S-wave velocities are positively correlated with erosion rate. We suggest that increasing erosion rates cause decreased residence time of rock masses within the critical zone, resulting in less weathered rocks.
- Keyword:
- rock strength, seismic, and erosion rate
- Citation to related publication:
- Townsend, K. F., Clark, M. K., & Zekkos, D. (2021). Profiles of Near-Surface Rock Mass Strength Across Gradients in Burial, Erosion, and Time. Journal of Geophysical Research: Earth Surface, 126(4), e2020JF005694. https://doi.org/10.1029/2020JF005694
- Discipline:
- Science
-
- Creator:
- Zhang, Yan, Gao, Chuanyu, Zhang, Shaoqing, Yang, Ping, Meyers, Philip A, and Wang, Guoping
- Description:
- The study focuses on reconstructing the histories of peat deposition using n-alkane biomarkers in peat cores and associated modern plant communities from four sites around a shallow maar lake in the Changbai Mountains of northeastern China. Peat development patterns in the four sites are not concordant although the sites experienced the same paleoclimate histories. Evidently, lava flows and tephra deposits produced an uneven topography of the volcanogenic lake basin that controls the water depths at the four lake edge locations, thereby leading to differences in peat-forming plant communities and peat deposition among the four sites.
- Keyword:
- peat deposition, n-alkanes, volcanic eruptions, and Changbai Lake
- Citation to related publication:
- Zhang, Y., Gao, C., Zhang, S., Yang, P., Meyers, P. A., & Wang, G. (2020). N-Alkane-based reconstructions of peat accumulations and depositional conditions at four locations around a shallow maar lake in the Changbai Mountains, northeastern China (world) [Preprint]. Earth and Space Science Open Archive; Earth and Space Science Open Archive. https://doi.org/10.1002/essoar.10505381.1
- Discipline:
- Science
-
- Creator:
- Moldwin, Mark B. and O'Brien, Paul
- Description:
- A new empirical model of the plasmapause location has been developed using density data from the plasma wave receiver onboard the CRRES spacecraft for nearly 1000 orbits. The “plasmapause” is identified here as the innermost sharp gradient in density (change of a factor of 5 in <0.5 L). Such a sharp gradient was observed on 73% of the CRRES inbound and outbound orbits that returned data. The plasmapause location is expressed as a linear function of Kp (previous 12 hour maximum) and local time. The model gives the linear best fit location of the plasmapause as well as the standard deviations of the model parameters.
- Keyword:
- Plasmapause and Plasmasphere
- Citation to related publication:
- Moldwin, M. B., Downward, L., Rassoul, H. K., Amin, R., and Anderson, R. R. (2002), A new model of the location of the plasmapause: CRRES results, J. Geophys. Res., 107( A11), 1339, doi:10.1029/2001JA009211 and O'Brien, T. P., and Moldwin, M. B. (2003), Empirical plasmapause models from magnetic indices, Geophys. Res. Lett., 30, 4, 1152. doi:10.1029/2002GL016007
- Discipline:
- Science
-
- Creator:
- Anahita, Amiri Farahani
- Description:
- this dataset is the output of WRF-Chem model for several simulations.
- Keyword:
- Lake spray aerosol
- Citation to related publication:
- Amiri-Farahani, A., Olson, N. E., Neubauer, D., Roozitalab, B., Ault, A. P., & Steiner, A. L. (2021). Lake Spray Aerosol Emissions Alter Nitrogen Partitioning in the Great Lakes Region. Geophysical Research Letters, 48(12), e2021GL093727. https://doi.org/10.1029/2021GL093727
- Discipline:
- Science
-
- Creator:
- Shane, Alexander
- Description:
- This data set was created with the purpose to study the electron pitch angle distributions on dayside closed crustal fields at Mars and to compare with theoretical predictions made by numerical modeling. Analyzing the plasma environment of the crustal fields was another point of study to determine if whistler waves can interact with high energy superthermal electrons.
- Keyword:
- Mars, superthermal electron, pitch angle distribution, and crustal magnetic field
- Discipline:
- Science
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Computed tomography voxel dataset for ummz:mammals:154693-Blarina brevicauda brevicauda-Skull-DiceCT
- Creator:
- University of Michigan Museum of Zoology
- Description:
- Scan of specimen ummz:mammals:154693 (Blarina brevicauda brevicauda) - Skull. Reconstructed Dataset includes 1219 TIF images (each 1013 x 1693 x 1 voxel at 0.033795 mm resolution, derived from 3141 scan projections), xtek and vgi files for volume reconstruction. and Scan of specimen ummz:mammals:154693 (Blarina brevicauda brevicauda) - Skull. Raw Dataset includes 3141 TIF images (each 1013 x 1693 x 1 voxel at 0.03379497 mm resolution, derived from 3141 scan projections), xtek and vgi files for volume reconstruction.
- Keyword:
- Animalia, Chordata, Mammalia, Soricomorpha, Soricidae, Blarina brevicauda brevicauda, 1987337719, computed tomography, X-ray, 3D, and DiceCT
- Citation to related publication:
- For more information on the original UMMZ specimen, see: https://www.gbif.org/occurrence/1987337719
- Discipline:
- Science