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F3UEL: Flaring & Fossil Fuels: Uncovering Emissions & Losses
User Collection
- Creator:
- Kort, Eric and Plant, Genevieve
- Description:
- Fossil energy production, processing, flaring, and transmission all can harm climate and air quality by emitting greenhouse gases and air pollutants. Studies now show that onshore oil and gas production emit much more methane than what is inventoried, and that local air quality impacts can be significant, however, natural gas flaring and offshore systems have been largely overlooked. The F3UEL (Flaring & Fossil Fuels: Uncovering Emissions & Losses) project aims to address these gaps by improving our understanding of offshore emissions, characterizing how flares behave in the real world, identifying what portion of the offshore system is responsible for emissions, and determining how such systems can be monitored. Spanning three years (2020-2022), the project employed an aircraft platform to measure including both greenhouse gas and air quality measurements. To sample the largest regions of current and potential future offshore production and flaring, airborne measurements targeted the Gulf of Mexico, offshore California and Alaska, the Bakken Formation (North Dakota) and the Permian and Eagle Ford Basins (Texas). Data provided here includes the airborne measurements collected using Scientific Aviation’s Mooney aircraft platform, equipped with spectroscopic instrumentation to measure methane, carbon dioxide, water vapor, nitrous oxide, and nitrogen oxide, in addition to meteorological variables such as wind speed and direction. Data products from our analysis of these airborne measurements are also provided, including estimated flare destruction removal efficiency for the Bakken, Eagle Ford, and Permian basins. Each data file is in .csv format and is accompanied by a readme file with further information and descriptors of the variables included. All users should cite the papers and datasets provided in the readme files for each individual dataset. Website: https://graham.umich.edu/f3uel This project is funded by the Alfred P. Sloan Foundation with additional support from the Environmental Defense Fund, Scientific Aviation, and University of Michigan (College of Engineering, Climate and Space Sciences and Engineering; Graham Sustainability Institute).
- Keyword:
- offshore oil & gas, flaring, methane, Nitrogen oxides, natural gas flaring, and oil & gas
- Discipline:
- Science
3Works -
- Creator:
- Engebretson, Mark J.
- Description:
- Large geomagnetic disturbances (GMDs, also denoted as MPEs - magnetic perturbation events) have sufficient amplitude to cause geomagnetically induced currents (GICs) that can damage technical infrastructure. In this study we present occurrence statistics for GMD / MPE events with derivatives ≥ 6 nT/s and ≥ 20 nT/s from five stations in the MACCS and AUTUMNX magnetometer arrays in Arctic Canada at magnetic latitudes ranging from 65° to 75°. Earlier studies using data from these arrays (Engebretson et al., 2019a,b, 2021a,b) covered only two years (2015 and 2017) and focused on latitude- and local time-dependent occurrence patterns and short-term dependencies on solar wind/IMF parameters and magnetospheric activity indices. This study presents all available data from these stations from 2011 through 2022 to analyze variations of GMD activity over a full solar cycle. Intense GMD activity did not closely follow the sunspot cycle, but instead was lowest during its rising phase and maximum (2011-2014), was highest during the early declining phase (2015-2017), and reached a subsequent minimum early in the following sunspot cycle (2020). GMDs with amplitude >20 nT/s followed the same yearly pattern but peaked even more strongly during 2015-2017. Most of these GMDs were associated with high-speed solar wind streams (Vsw > 600 km/s), but not with strongly negative values of the SYM/H index. The majority of these GMDs, irrespective of the Vsw value, were accompanied within 10 min (and most often less) by other events with amplitude ≥ 6 nT/s and showed a mostly poleward progression. These results show that large amplitude but spatially localized nighttime GMDs are primarily associated with high-speed stream geomagnetic drivers during the declining phase of the solar cycle. This indicates that large GIC hazard conditions can occur for a variety of solar wind drivers and geomagnetic conditions and not only for fast-coronal mass ejection driven storms.
- Keyword:
- geomagnetic disturbance events, geomagnetically induced currents
- Citation to related publication:
- Engebretson, M. J., Steinmetz, Yang, L., Pilipenko, V. A., Moldwin, M. B., McCuen, B. A., Connors, M. G., Weygand, J. M., Waters, C. L., Lyons, L. R., Nishimura, Y., Russell, C. T. (2023) Solar Cycle Dependence of Very Large Nighttime Geomagnetic Disturbances (GMDs) Observed in Eastern Arctic Canada. Journal of Geophysical Research – Space Physics
- Discipline:
- Science
-
- Creator:
- Kort, Eric A., Plant, Genevieve, Brandt, Adam R., Chen, Yuanlei, Fordice, Graham, Gorchov Negron, Alan M., Schwietzke, Stefan, Smith, Mackenzie, and Zavala-Araiza, Daniel
- Description:
- As part of the Flaring & Fossil Fuels: Uncovering Emissions & Losses (F3UEL) project ( https://graham.umich.edu/f3uel), the aircraft measurement platform sampled downwind of flares in the Permian and Eagle Ford regions of Texas (2020) and the Bakken in North Dakota (2021). Estimates of methane destruction removal efficiency are calculated for each airborne intercept of a flare combustion plume based on the observed enhancements of carbon dioxide and methane, along with assumptions about the flare gas composition. Locations provided are the GPS coordinates for the aircraft sampling, not of the upwind flare infrastructure on the ground. Attempts to link the airborne sampling locations to ground infrastructure using the provided wind information (measured at the aircraft), should take care to account for transport in the atmosphere.
- Keyword:
- Natural Gas Flaring, Methane, and Oil & Gas
- Citation to related publication:
- Plant, G., Kort, E. A., Brandt, A. R., Chen, Y., Fordice, G., Gorchov Negron, A. M., Schwietzke, S., Smith, M., & Zavala-Araiza, D. (2022). Inefficient and unlit natural gas flares both emit large quantities of methane. Science, 377(6614), 1566–1571. https://doi.org/10.1126/science.abq0385, Kort, E. A., Plant, G., Smith, M. L., Brandt, A. R., Chen, Y., Gorchov Negron, A. M., Schwietzke, S., Zavala-Araiza, D. (2022). Aircraft Data (2020) for Flaring & Fossil Fuels: Uncovering Emissions & Losses (F3UEL), University of Michigan - Deep Blue Data. https://doi.org/10.7302/1xjm-3v49, and Kort, E. A., Plant, G., Brandt, A. R., Chen, Y., Gorchov Negron, A. M., Schwietzke, S., Smith, M. L., Zavala-Araiza, D. (2022). Aircraft Data (2021) for Flaring & Fossil Fuels: Uncovering Emissions & Losses (F3UEL), University of Michigan - Deep Blue Data. https://doi.org/10.7302/6tgq-e116
- Discipline:
- Science
-
- Creator:
- Sun, Hu
- Description:
- Complete Global Total Electron Content Database based on the VISTA Algorithm
- Keyword:
- Total Electron Content, Matrix Completion, VISTA, Spherical Harmonics, and Spatial-Temporal Smoothing
- Discipline:
- Engineering
2Works -
Data for Macroscopic Transition Metal Dichalcogenides Monolayers with Uniformly High Optical Quality
- Creator:
- Li, Qiuyang, Alfrey, Adam, Hu, Jiaqi, Lydick, Nathanial, Paik, Eunice, Liu, Bin, Sun, Haiping, Lu, Yang, Wang, Ruoyu, Forrest, Stephen, and Deng, Hui
- Description:
- This dataset contains raw and source data for all figures generated in the manuscript "Macroscopic Transition Metal Dichalcogenides Monolayers with Uniformly High Optical Quality" The raw data files include '.spe' data, which are spectral data collected by LightField Sofware, and '.dset' and '.vms' files, which are X-ray photoelectron spectroscopy (XPS) data and require CasaXPS to access. The source data files include the processed data that can be directly used for generating the corresponding figures in the manuscript.
- Keyword:
- 2D materials, Exciton-polaritons, and Photonics
- Discipline:
- Science
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Mound survey
User Collection
- Creator:
- Galaty, Michael
- Description:
- TBD
- Keyword:
- archaeology
- Discipline:
- Humanities and Social Sciences
0Works -
- Creator:
- Walsh, Lisa L
- Description:
- Stable isotope values of carbon (δ13C) and nitrogen (δ15N) from Virginia opossum (Didelphis virginiana) guard hairs were analyzed to evaluate the ecology and winter adaptations in opossums by Dr. Lisa L. Walsh as part of her Ph.D. thesis in the Ecology and Evolutionary Biology Department. The collection of stable isotope data took place from 2017 to 2019. Guard hair was processed at the University of Michigan and analyzed by the University of New Mexico Center for Stable Isotopes (UNM-CSI, USA). Captive and wild opossums were evaluated for evidence of biannual or incomplete biannual molting, a mammalian adaptation to harsh winters. Results suggest opossums do not exhibit either winter molting strategy and that guard hairs capture the opossum’s lifetime diet (Walsh and Tucker 2021). The stable isotope values were used to test the hypothesis that a Type A generalist’s niche is positively correlated with habitat heterogeneity and to evaluate which climate variables best explained isotope values. There was a positive correlation between isotopic niche size and habitat-diversity indexes (Walsh and Tucker 2020). The δ13C values from opossums in the Midwest and Northeast to test whether opossums rely on anthropogenic trash to survive extreme winters. There was no significant relationship between δ13C and winter variables, but there was a significant increase in variance of Midwest opossums’ δ13C after the 1970 corn agricultural boom (Walsh and Tucker 2023).
- Keyword:
- stable isotope, Virginia opossum, mesopredator, ecology, and mammal
- Citation to related publication:
- Walsh, L.L. and P.K. Tucker. 2020. Habitat heterogeneity is correlated with isotopic niche breadth across the range of a mammalian generalist mesopredator. Ecosphere, 11(12): e03314. https://doi.org/10.1002/ecs2.3314, Walsh, L.L. and P.K. Tucker. 2021. Stable isotope values suggest opossums (Didelphis virginiana) at their northern edge do not seasonally molt. Northeastern Naturalist, 28(1): 1-8. https://doi.org/10.1656/045.028.0101, and Walsh, L.L., and P.K. Tucker. 2023. Evaluating anthropogenic influence on a mesopredator: Opossum (Didelphis virginiana) isotope values influenced by corn agriculture more than urbanization. Canadian Journal of Zoology, 101: https://doi.org/10.1139/cjz-2021-0172.
- Discipline:
- Science
-
- Creator:
- Billings, Gideon H and Johnson-Roberson, Matthew
- Description:
- UWslam is a dataset for underwater stereo and hybrid monocular fisheye + stereo SLAM in natural seafloor environments. The dataset includes a spiral survey of a shallow reef captured with a diver operated stereo rig and 4 hybrid image sequences captured with a deep ocean ROV in different deep ocean environments. Ground truth pose estimates for the spiral stereo trajectory were obtained by processing the image sequence through COLMAP. Ground truth pose estimates for the hybrid sequences were obtained by distributing fiducials on the seafloor before capturing an image sequence and processing the image sequences with the ROS based TagSLAM package.
- Keyword:
- SLAM, Simultaneous Localization and Mapping, Visual Reconstruction, and Underwater
- Citation to related publication:
- G. Billings, R. Camilli and M. Johnson-Roberson, "Hybrid Visual SLAM for Underwater Vehicle Manipulator Systems," in IEEE Robotics and Automation Letters, vol. 7, no. 3, pp. 6798-6805, July 2022, doi: 10.1109/LRA.2022.3176448.
- Discipline:
- Engineering
-
- Creator:
- Billings, Gideon H and Johnson-Roberson, Matthew
- Description:
- UWHandles is a dataset for 6D object pose estimation in underwater fisheye images. It provides 6D pose and 2D bounding box annotations for 3 different graspable handle objects used for ROV manipulation. The dataset consists of 28 image sequences collected in natural seafloor environments with a total of 20,427 annotated frames. and Meta repository for the dataset https://github.com/gidobot/UWHandles
- Keyword:
- Deep Learning, Pose Estimation, and Underwater Vision
- Citation to related publication:
- Billings, G., & Johnson-Roberson, M. (2020). SilhoNet-fisheye: Adaptation of a ROI based object pose estimation network to monocular fisheye images. IEEE Robotics and Automation Letters, 5(3), 4241-4248.
- Discipline:
- Engineering
-
- Creator:
- Jenkins, G. J. and Bougher, S. W.
- Description:
- In early 2019, the Mars Atmosphere and Volatile Evolution (MAVEN) mission underwent an ~2-month aerobraking campaign, during which time the spacecraft periapsis altitude was lowered from its nominal altitude range of 140-160 km to as low as ~123 km. Excluding spacecraft walk-in/out maneuvers, accelerometer measurements were made along 272 orbits with coverage spanning Ls 340-3°, latitudes ~5-54°S, longitudes 0-360°, and Local Solar Time (LST) ~22-17 hours. In this study, we perform a diagnostic analysis of the full aerobraking data set by fitting 4-harmonic waves to mass densities. We then study the variations of these waves as a function of latitude with an emphasis on those observed previously in Mars’ thermosphere by MAVEN and other missions. Additionally, we utilize data collected during the same time period from the Mars Reconnaissance Orbiter’s Mars Climate Sounder to study the vertical propagation of waves originating from the middle atmosphere. Key results indicate that normalized wave amplitudes decrease with latitude, and this is consistent with the latitudinal structure of a diurnal Kelvin mode. We also observe that waves imprinted from the middle atmosphere show normalized amplitude growth with increasing altitude. A complete summary of data sets, analysis methodology, and scientific results is given. The purpose of this study is to add to the body of knowledge surrounding Martian atmospheric wave features and to provide further constraints for future numerical modeling and subsequent tidal mode identification.
- Keyword:
- MAVEN, Mars Thermosphere, Accelerometer Data Set, Global Data Set, and Wave Analysis of Tides
- Citation to related publication:
- Jenkins, G. A., Bougher, S. W., Lugo, R., Tolson, R. H., Zurek, R. W., Baird, D., Steele, L., Kass, D., Withers, P. (2023), MAVEN Accelerometer Observations of Thermospheric Densities during Aerobraking and Deep Dip 2: Wave Features and Connections to Upward Propagating Thermal Tides, Journal of Geophysical Research: Planets, xx, xx.
- Discipline:
- Science