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Dynamical Heating in the Martian Thermosphere: Temperatures, Winds and Thermal Balances using M-GITM
- Creator:
- Bougher, S. W. and Pilinski, M. D.
- 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 have also been conducted once per month for 5-10 orbits since 2016. 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, in-situ measured winds and corresponding argon density derived temperatures are combined to trace the circulation patterns and investigate their convergence and divergence locations and impacts throughout the Mars thermosphere. M-GITM computed thermal balance terms are subsequently extracted to investigate the processes required to maintain the temperature distribution around the planet. For this work, Mars Year #33 (MY33) Neutral Gas and Ion Mass Spectrometer (NGIMS) measurements have been obtained by the MAVEN team for this purpose (see these representative works: (Bougher et al., 2017; Stone et al., 2018; Benna et al., 2019). These temperature and wind fields 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 temperature distributions and underlying thermal balances throughout the atmosphere. Three dimensional M-GITM simulations for three of the four Mars cardinal seasons (Ls = 0, 90, 270) for MY33 were conducted for detailed comparisons with NGIMS temperature and wind distributions (Pilinski et al. 2022). Corresponding M-GITM datacubes used to extract these temperatures (plus winds) along the trajectory of each orbit path between 140 and 240 km, are provided in this Deep Blue Data archive. A single README file is included that details the contents of each datacube file. In addition, this general README file summarizes the inputs and outputs of each M-GITM simulation interval used for this study. Finally, a basic version of the M-GITM code can be found on Github at https:/github.com/dpawlows/MGITM.
- Keyword:
- MAVEN, Mars thermosphere, global dynamics, and heat balances owing to winds
- Citation to related publication:
- Pilinski, M. D., K. J. Roeten, S. W. Bougher and M. Benna, Dynamical Heating in the Martian Thermosphere, Journal Geophysical Res., XXX, (forthcoming - 2022). doi: .....
- Discipline:
- Science
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- Creator:
- Zhou, Peng and Mi, Zetian
- Description:
- Production of hydrogen fuel from sunlight and water offers one of the most promising pathways for carbon neutrality. Some solar hydrogen production approaches, e.g., photoelectrochemical water splitting, often requires corrosive electrolyte, limiting their performance stability and environmental sustainability. Alternatively, clean hydrogen can be produced directly from tap water, or seawater by wireless photocatalytic water splitting. The solar-to-hydrogen (STH) efficiency, however, is still lower than 3%. Herein, we have developed a unique strategy to overcome the efficiency bottleneck. A high STH efficiency of 9.2% was achieved by utilizing pure water, concentrated solar light, and visible-light-responsive InGaN photocatalyst. The success of this strategy was explained by the synergistic effects of promoting forward hydrogen-oxygen evolution and inhibiting the reverse hydrogen-oxygen recombination by operating at an optimal reaction temperature (~70 °C). Such an optimal temperature can be readily achieved by harvesting the previously wasted infrared light of the solar spectrum without other energy consumption. This temperature-dependent strategy also leads to the STH efficiencies of ~7% from the widely available tap water and seawater. A large-scale photocatalytic water splitting system with a natural solar light capacity of 257 W on a 4 cm × 4 cm photocatalyst wafer achieves a STH of 6.2% at ~70 oC. Our study offers a practical approach to produce hydrogen fuel efficiently from natural solar and water, overcoming some of the major barriers for green hydrogen economy.
- Keyword:
- photocatalysis, water splitting, and solar hydrogen
- Discipline:
- Science
-
- Creator:
- Jivani, Aniket, Sachdeva, Nishtha, Huang, Zhenguang, Chen, Yang, van der Holst, Bart, Manchester, Ward, Iong, Daniel, Chen, Hongfan, Zou, Shasha, Huan, Xun, and Toth, Gabor
- Description:
- In this work, we perform Global Sensitivity Analysis (GSA) for the background solar wind in order to quantify contributions from uncertainty of different model parameters to the variability of in-situ solar wind speed and density at 1au, both of which have a major impact on CME propagation and strength. Scripts written in the Julia language are used to build the PCE and calculate the sensitivity results. Data is available in csv, NetCDF and JLD files. A `Project.toml` file is included to activate and install all required dependencies (See README for details).
- Keyword:
- Uncertainty Quantification, Space Weather, and Global Sensitivity Analysis
- Discipline:
- Engineering
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- Creator:
- Bougher, S. W. and Parkinson, C. D.
- Description:
- Understanding the state and composition of an exoplanetary atmosphere depends upon several parameters such as heating, cooling, mixing and reactions between constituent chemical species. Only a few types of atmospheric species can be detected remotely spectroscopically and only if their abundance is large enough to be detectable. In this initial study, we model the atmosphere of a Venus-like planet orbiting the M-type star GJ 436 to determine the global neutral temperature structure, winds, and energy balance as the radial distance of the planet from the star decreases.
- Keyword:
- Venus-like exoplanet, upper atmospheres , and heat balances
- Citation to related publication:
- C. D. Parkinson, S. W. Bougher, F. P. Mills, R. Hu, G. Gronoff, J. Li, A. Brecht, D. Adams, and Y. L. Yung. Venus as an Exoplanet: I. An Initial Exploration of the 3-D Energy Balance for a CO2 Exoplanetary Atmosphere Around an M-Dwarf Star, J. Geophysical Research, X, (2022). doi:....
- Discipline:
- Science
-
- Creator:
- Limon, Garrett C.
- Description:
- The data represents weekly output from three 60-year CAM6 model runs. The output includes state (.h0. files) and tendency (.h1. files) fields for three difference model configurations of increasing complexity. State fields include temperature, surface pressure, specific humidity, among others; while tendencies include temperature tendencies, specific humidity tendencies, as well as precipitation rates. Using the state variables at a given time step, machine learning techniques can be trained to predict the following tendency field, which can then be applied to the state variables to provide the state at the next physics time step of the model.
- Keyword:
- Machine Learning, Climate Modeling, and Physics Emulation
- Citation to related publication:
- Limon, G. C., Jablonowski, C. (2022) Probing the Skill of Random Forest Emulators for Physical Parameterizations via a Hierarchy of Simple CAM6 Configurations [Preprint]. ESSOAr. https://10.1002/essoar.10512353.1
- Discipline:
- Engineering and Science
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- Creator:
- University of Michigan Museum of Paleontology, Nondestructive Evaluation Laboratory, Ford Motor Company, and Jones, Martin
- Description:
- Reconstructed CT slices for a right tusk of Loxodonta africana (University of Michigan Museum of Paleontology catalog number UMMP_VP_118186) as a series of TIFF images. Raw projections are not included in this dataset. The reconstructed slice data from the scan are offered here as a series of unsigned 16-bit integer TIFF images. The upper left corner of the first image (*_000.tif) is the XYZ origin. Metadata as produced by the Aracor system are included in *.IM$LA text files in IM$LA.zip.
- Keyword:
- Paleontology, CT, Elephantidae, UMMP, University of Michigan Museum of Paleontology, and a4f83cc6-09f2-0032-8a09-60ea798f787c
- Citation to related publication:
- Cherney, M., et al. (in prep)
- Discipline:
- Science
-
- Creator:
- Huber, Daniel E
- Description:
- The files here provide monthly averaged soil NOx emissions (units of ng N m^-2 s^-1) for the contiguous United States on a 0.25 degree x 0.25 degree grid for the years 2011-2020 .
- Keyword:
- soil NOx, soil emissions, biogenic emissions, and agricultural emissions
- Discipline:
- Science
-
- Creator:
- Sun, Hu, Ren, Jiaen, Chen, Yang, Zou, Shasha, Chang, Yurui, Wang, Zihan, and Coster, Anthea
- Description:
- Our research focuses on providing a fully-imputed map of the worldwide total electron content with high resolution and spatial-temporal smoothness. We fill in the missing values of the original Madrigal TEC maps via estimating the latent feature of each latitude and local time along the 2-D grid and give initial guess of the missing regions based on pre-computed spherical harmonics map. The resulting TEC map has high imputation accuracy and the ease of reproducing. All data are in HDF5 format and are easy to read using the h5py package in Python. The TEC map is grouped in folders based on years and each file contains a single-day data of 5-min cadence. Each individual TEC map is of size 181*361. and WARNING: 2023-12-01 the data file for 2019-Jan-03 has badly fitted values. Please avoid using it. All other days' files are ready to use.
- Keyword:
- Total Electron Content, Matrix Completion, VISTA, Spherical Harmonics, and Spatial-Temporal Smoothing
- Citation to related publication:
- Sun, H., Hua, Z., Ren, J., Zou, S., Sun, Y., & Chen, Y. (2022). Matrix completion methods for the total electron content video reconstruction. The Annals of Applied Statistics, 16(3), 1333-1358., Sun, H., Chen, Y., Zou, S., Ren, J., Chang, Y., Wang, Z., & Coster, A. (2023). Complete Global Total Electron Content Map Dataset based on a Video Imputation Algorithm VISTA. Scientific Data, in press., and Zou, S., Ren, J., Wang, Z., Sun, H., & Chen, Y. (2021). Impact of storm-enhanced density (SED) on ion upflow fluxes during geomagnetic storm. Frontiers in Astronomy and Space Sciences, 8, 746429.
- Discipline:
- Science and Engineering
-
- Creator:
- Goodrich, Jaclyn M., Tang, Lu, Rodríguez-Carmona, Yanelli, Meijer, J L., Perng, Wei, Watkins, Deborah J., Meeker, John D. , Mercado-García, Adriana, Cantoral, Alejandra, Song, Peter X. , Téllez-Rojo, Martha M. , and Peterson, Karen E.
- Description:
- Phthalates are chemicals found in many products that humans are exposed to. Prenatal exposure to phthalates has been associated with adverse outcomes that are detected in childhood, adolescence, and even adulthood. In this study, we sought to identify subtle biological changes in the metabolome of children that were exposed to phthalates during gestation. We hypothesized that prenatal phthalate exposures would alter metabolic pathways related to adiposity and cardiometabolic health. The article is under review (citation to be added when paper is published). The data included here encompass all exposure, demographic, and untargeted metabolomics data needed for the analysis described in the manuscript.
- Keyword:
- Phthalates , Prenatal, and Metabolomics
- Citation to related publication:
- Goodrich J.M., Tang L.,Rodríguez-Carmona Y., Meijer J.L, Perng W., Watkins D.J., Meeker J.D., Mercado-García A., Cantoral A., Song P.X., Téllez-Rojo M.M., Peterson K.E. Trimester-specific phthalate exposures in pregnancy are associated with circulating metabolites in children. PLoS One. (Under revision – forthcoming.)
- Discipline:
- Other and Health Sciences
-
- Creator:
- University of Michigan Museum of Paleontology and CTEES
- Description:
- Reconstructed CT slices for vertebrae of Hyopsodus (University of Michigan Museum of Paleontology catalog number UMMP_VP_102495) as a series of TIFF images. Raw projections are not included in this dataset. The reconstructed slice data from the scan are offered here as a series of unsigned 16-bit integer TIFF images. The upper left corner of the first image (*_0000.tif) is the XYZ origin.
- Keyword:
- Paleontology, Fossil, CT, Hyopsodontidae, UMMP, University of Michigan Museum of Paleontology, Eocene, CTEES, and 01ee73fb-6b53-fe52-3a01-2857be88a65e
- Discipline:
- Science