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- Creator:
- Roeten, K. J. and Bougher, S. W.
- Description:
- In order to better understand the large-scale impacts of smaller-scale gravity waves in the upper atmosphere of Mars, a modern whole atmosphere, nonlinear, non-orographic, spectral gravity wave parameterization scheme (Yigit et al., 2008) has been added to the ground-to-exosphere 3-D general circulation model, M-GITM (Bougher et al., 2015), which previously did not account for the effects of this physical process. New atmospheric simulations have been run for cases which did and did not utilize this gravity wave parameterization as well as for cases designed to test the sensitivity of certain adjustable parameters within the scheme. After including the gravity wave parameterization scheme into M-GITM, large impacts are found on the simulated mean thermospheric horizontal velocities and temperature structure, especially within the altitude range of 90-170 km (Roeten et al., 2022). The most notable of these impacts include a reduction in speed of the thermospheric easterlies in the summer hemisphere as well as overall cooling, on average, at altitudes above 120 km., Simulations were run for two different seasons at Mars, a solstice (Ls=270) and an equinox (Ls=180). The output from these simulations have been averaged over all local times over a 15-day time period, starting on the day of the solstice or equinox. The output has also been zonally averaged over all longitudes. Files containing these zonally and temporally averaged files are named starting with “MGITM_ZonalAvg”. Both solstice and equinox cases have been simulated once without including the gravity wave parameterization (“nogw”) and once with the gravity wave parameterization included (“withgw”). Additional simulations of the Ls=270 solstice have been done individually adjusting the horizontal wavelength and maximum source flux parameters within the gravity wave scheme. , and Other M-GITM simulations have also been provided in a different format. These M-GITM simulations are ‘flythroughs’ of model output, extracted along the same trajectory path of the MAVEN spacecraft, which allows for better data-model comparisons with in-situ MAVEN/NGIMS (Neutral Gas and Ion Mass Spectrometer) observations. These simulations have been done for three different NGIMS observational campaigns, both for cases that include and do not include the effects of gravity waves. Output from these simulations has NOT been averaged; instead, output from each simulated MAVEN orbit is included within the file. These files are named starting with “MGITM_TempExtraction” or “MGITM_WindExtraction” based on whether the MGITM flythrough was designed to be compared to MAVEN/NGIMS temperature or wind profiles, respectively.
- Keyword:
- Mars, M-GITM, MAVEN, and Mars upper atmosphere
- Citation to related publication:
- Roeten, K. J., Bougher, S. W., Yigit, E., Medvedev, A. S., Benna, M., Elrod, M. K. (2022). Impacts of gravity waves in the Martian thermosphere: The Mars Global Ionosphere- Thermosphere Model coupled with a whole atmosphere gravity wave scheme. Journal of Geophysical Research: Planets. In preparation.
- Discipline:
- Science
-
- Creator:
- Bougher, Stephen W. and Roeten, Kali J.
- Description:
- The NASA MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft, which is currently in orbit around Mars, has been taking systematic measurements of the densities and deriving temperatures in the upper atmosphere of Mars between about 140 to 240 km above the surface since late 2014. Wind measurement campaigns are also conducted once per month for 5-10 orbits. These densities, temperatures and winds change with time (e.g. solar cycle, season, local time) and location, and sometimes fluctuate quickly. Global dust storm events are also known to significantly impact these density, temperature and wind fields in the Mars thermosphere. For the current project, the derived temperatures and O plus CO2 densities are used to characterize the upper atmosphere dayside thermal and density structure. Presently, more than 6 years of Neutral Gas and Ion Mass Spectrometer (NGIMS) measurements of neutral densities have been obtained by the MAVEN team (e.g. Mahaffy et al. 2015; Bougher et al 2015; Elrod et al., 2017; 2021; Stone et al. 2018; Gupta et al., 2021). Measured neutral density distributions are compared to simulations from a computer model of the Mars atmosphere called M-GITM (Mars Global Ionosphere-Thermosphere Model), developed at U. of Michigan. Since the global circulation plays a role in the structure, variability, and evolution of the atmosphere, understanding the processes that drive the winds in the upper atmosphere of Mars also provides the needed context for understanding density and temperature distributions and how the atmosphere behaves as a whole system. Three dimensional M-GITM simulations for extreme Mars seasonal and solar cycle conditions were conducted for detailed comparisons with NGIMS derived temperatures and O/CO2 ratio distributions (Bougher et al. 2022). Extracted model densities and temperatures along the MAVEN inbound trajectory of each orbit path (between ~300 km and periapsis) are provided in this Deep Blue Data archive. Corresponding M-GITM heat balance terms are also provided in vertical 1-D tabulated formats. README files are included for each suite of 1-D "flythru" tables, detailing the contents of each file. In addition, a general README file is provided that summarizes the inputs and outputs of the M-GITM code simulations for this study. Finally, a basic version of the M-GITM code can be found on Github at https:/github.com/dpawlows/MGITM.
- Keyword:
- Mars, NASA MAVEN Mission, NGIMS instrument , and M-GITM numerical simulations
- Citation to related publication:
- Bougher, S. W., Benna, M., Elrod, M., Roeten, K., & Thiemann, E. (2023). MAVEN/NGIMS dayside exospheric temperatures over solar cycle and seasons: Role of dayside thermal balances in regulating temperatures. Journal of Geophysical Research: Planets, 128, e2022JE007475. https://doi.org/10.1029/2022JE007475
- Discipline:
- Science
-
Bounce-Averaged Quasi-Linear Diffusion Model Simulation Input/Output on Mars’ Crustal Magnetic Field
- Creator:
- Alexander Shane
- Description:
- To study the effect of whistler mode waves on the superthermal electron velocity space at Mars, a numerical model was built to solve the bounce-averaged quasi-linear diffusion equation on a crustal field. This dataset includes the input and output variables to this model for the simulations performed in Shane and Liemohn, 2022. The studies using this dataset were conducted by Alex Shane in the Climate and Space Sciences and Engineering Department at the University of Michigan. This research was supported by the National Aeronautics and Space Administration (NASA) Grant NNX16AQ04G to the University of Michigan and the Rackham Predoctoral Fellowship.
- Keyword:
- Mars, Electron, and Crustal Fields
- Citation to related publication:
- Shane, A. D., & Liemohn, M. W. (2022). Modeling wave-particle interactions with photoelectrons on the dayside crustal fields of Mars. Geophysical Research Letters, 49, e2021GL096941. https://doi.org/10.1029/2021GL096941
- Discipline:
- Science
-
- Creator:
- Bougher, S. W. (CLaSP Department, University of Michigan)
- Description:
- The NASA MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft, which is currently in orbit around Mars, has been taking systematic measurements of the densities and deriving temperatures in the upper atmosphere of Mars between about 140 to 240 km above the surface since late 2014. Wind measurement campaigns are also conducted once per month for 5-10 orbits. These densities, temperatures and winds change with time (e.g. solar cycle, season, local time) and location, and sometimes fluctuate quickly. Global dust storm events are also known to significantly impact these density, temperature and wind fields in the Mars thermosphere. For the current project, the inert light species helium is used to trace the circulation patterns and constrain wind magnitudes throughout the Mars thermosphere. Presently, more than 6 years of Neutral Gas and Ion Mass Spectrometer (NGIMS) measurements of helium densities have been obtained by the MAVEN team (e.g. Elrod et al., 2017; 2021; Gupta et al., 2021). Measured helium distributions are compared to simulations from a computer model of the Mars atmosphere called M-GITM (Mars Global Ionosphere-Thermosphere Model), developed at U. of Michigan. Since the global circulation plays a role in the structure, variability, and evolution of the atmosphere, understanding the processes that drive the winds in the upper atmosphere of Mars also provides the needed context for understanding helium distributions and how the atmosphere behaves as a whole system. Three dimensional M-GITM simulations for the Mars four cardinal seasons (Ls = 0, 90, 180, 270, for Mars Year 33) were conducted for detailed comparisons with NGIMS helium and CO2 distributions (Gupta et al. 2021). The M-GITM datacubes used to extract these densities (plus winds) along the trajectory of each orbit path between 140 and 240 km, are provided in this Deep Blue Data archive. README files are also provided for each datacube, detailing the contents of each file. In addition, a general README file is provided that summarizes the inputs and outputs of the M-GITM code simulations for this study. Finally, a basic version of the M-GITM code can be found on Github at https:/github.com/dpawlows/MGITM.
- Keyword:
- Mars, MAVEN Spacecraft Mission, Mars Thermosphere, Helium Density Distributions, and Neutral Gas and Ion Mass Spectrometer (NGIMS)
- Citation to related publication:
- Gupta, N., N. V. Rao, S. W. Bougher, and M. K. Elrod, Latitudinal and Seasonal Asymmetries of the Helium Bulge in the Martian Upper Atmosphere J. Geophys. Res., 126, XXXX-XXXX. doi:10.1002/2021JEXXXXXX
- Discipline:
- Engineering and 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
-
- Creator:
- Bougher, S. W. (CLaSP Department, U. of Michigan), Roeten, K. J. (CLaSP Department, U. of Michigan), and Sharrar, R. (Astronomy Department, U. of Michigan)
- Description:
- The NASA MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft, which is currently in orbit around Mars, has been taking daily (systematic) measurements of the densities and temperatures in the upper atmosphere of Mars between about 140 to 240 km above the surface. Wind measurement campaigns are also conducted once per month for 5-10 orbits. These densities, temperatures and winds change with time (e.g. season, local time) and location, and sometimes fluctuate quickly. Global dust storm events are also known to significantly impact these density, temperature and wind fields in the Mars thermosphere. Such global dust storm period measurements can be compared to simulations from a computer model of the Mars atmosphere called M-GITM (Mars Global Ionosphere-Thermosphere Model), developed at U. of Michigan. This is the first detailed comparison between direct global dust storm period measurements in the upper atmosphere of Mars and simulated MGITM fields and is important because it can help to inform us what physical processes are acting on the upper atmosphere during such large dust events. Since the global circulation plays a role in the structure, variability, and evolution of the atmosphere, understanding the processes that drive the winds in the upper atmosphere of Mars also provides key context for understanding how the atmosphere behaves as a whole system. A basic version of the M-GITM code can be found on Github as follows: https:/github.com/dpawlows/MGITM and About 4 months of Neutral Gas and Ion Mass Spectrometer (NGIMS) measurements of densities and winds have been made by the MAVEN team during the summer of 2018 (Elrod et al., 2019). Nine reference measurement intervals during this global dust storm (1-June through 30-August 2018) are selected for detailed study (Elrod et al. 2019). The Mars conditions for these nine intervals have been used to launch corresponding M-GITM code simulations, yielding 3-D neutral density, temperature and wind fields for comparison to these NGIMS measurements. The M-GITM datacubes used to extract the density, temperature and neutral winds, along the trajectory of each orbit path between 140 and 240 km, are provided in this Deep Blue Data archive. README files are provided for each datacube, detailing the contents of each file. A general README file is also provided that summarizes the inputs and outputs of the M-GITM code simulations for this study.
- Keyword:
- Mars, MAVEN Spacecraft, Mars Thermosphere, and Mars Global Dust Storm of 2018
- Citation to related publication:
- Elrod, M. K., S. W. Bougher, K. Roeten, R. Sharrar, J. Murphy, Structural and Compositional Changes in the Upper Atmosphere related to the PEDE-2018 Dust Event on Mars as Observed by MAVEN NGIMS, Geophys. Res. Lett., (2019). doi: 10.1029/2019GL084378. and Jain, S. K., Bougher, S. W., Deighan, J., Schneider, N. M., Gonzalez‐Galindo, F., Stewart, A. I. F., et al. ( 2020). Martian thermospheric warming associated with the Planet Encircling Dust Event of 2018. Geophysical Research Letters, 47, e2019GL085302. https://doi.org/10.1029/2019GL085302
- Discipline:
- Engineering and Science
-
- Creator:
- Bougher, Stephen W. (CLaSP Department, U. of Michigan) and Roeten, Kali J. (CLaSP Department, U. of Michigan)
- Description:
- The NASA MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft, which is currently in orbit around Mars, has been taking monthly measurements of the speed and direction of the winds in the upper atmosphere of Mars between about 140 to 240 km above the surface. The observed wind speeds and directions change with time and location, and sometimes fluctuate quickly. These measurements are compared to simulations from a computer model of the Mars atmosphere called M-GITM (Mars Global Ionosphere-Thermosphere Model), developed at U. of Michigan. This is the first comparison between direct measurements of the winds in the upper atmosphere of Mars and simulated winds and is important because it can help to inform us what physical processes are acting on the observed winds. Some wind measurements have similar wind speeds or directions to those predicted by the M-GITM model, but sometimes, there are large differences between the simulated and measured winds. The disagreements between wind observations and model simulations suggest that processes other than normal solar forcing may become relatively more important during these observations and alter the expected circulation pattern. Since the global circulation plays a role in the structure, variability, and evolution of the atmosphere, understanding the processes that drive the winds in the upper atmosphere of Mars provides key context for understanding how the atmosphere behaves as a whole system. A basic version of the M-GITM code can be found on Github as follows: https:/github.com/dpawlows/MGITM and About 30 Neutral Gas and Ion Mass Spectrometer (NGIMS) wind campaigns (of 5 to 10 orbits each) have been conducted by the MAVEN team (Benna et al., 2019). Five of these campaigns are selected for detailed study (Roeten et al. 2019). The Mars conditions for these five campaigns have been used to launch corresponding M-GITM code simulations, yielding 3-D neutral wind fields for comparison to these NGIMS wind observations. The M-GITM datacubes used to extract the zonal and meridional neutral winds, along the trajectory of each orbit path between 140 and 240 km, are provided in this Deep Blue Data archive. README files are provided for each datacube, detailing the contents of each file. A general README file is also provided that summarizes the inputs and outputs of the M-GITM code simulations for this study.
- Keyword:
- Mars, MAVEN spacecraft, Mars thermosphere, and Mars global upper atmosphere winds
- Citation to related publication:
- Roeten, K. J., Bougher, S. W., Benna, M., Mahaffy, P. R., Lee, Y., Pawlowski, D., et al. (2019). MAVEN/NGIMS thermospheric neutral wind observations: Interpretation using the M‐GITM general circulation model. Journal of Geophysical Research: Planets, 124, 3283– 3303. https://doi.org/10.1029/2019JE005957
- Discipline:
- Science and Engineering
-
- Creator:
- Regoli, Leonardo H.
- Description:
- The data corresponds to outputs from the Mars Global Ionosphere Thermosphere Model (M-GITM), the multi-species magnetohydrodynamics (MS-MHD) and multi-fluid magnetohydrodynamics (MF-MHD) codes used during the study presented in "Multi-species and multi-fluid MHD approaches for the study of ionospheric escape at Mars" by Regoli et al. and Dataset citation: Regoli, L.H. (2018). Model outputs for "Multi-species and multi-fluid MHD approaches for the study of ionospheric escape at Mars" [Data set]. University of Michigan Deep Blue Data Repository. https://doi.org/10.7302/Z2GH9G49
- Keyword:
- GCM, MHD, and Mars
- Citation to related publication:
- Regoli, L.H., Dong, C., Ma, Y.J., Dubinin, E., Manchester, W.B., Bougher, S.W., & Welling, D.T. (2018). Multispecies and multifluid MHD approaches for the study of ionospheric escape at Mars. Journal of Geophysical Research: Space Physics, 123. https://doi.org/10.1029/2017JA025117
- Discipline:
- Science