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- Creator:
- Bradshaw, Lisa, Vernon, Julianne, Schmidt, Thomas, James, Timothy, Zhang, Jianzhi, Archbold, Hilary, Cadigan, Ken, Wolfe, John P., and Goldberg, Deborah E.
- Description:
- This is the experimental data referenced in our manuscript entitled "Influence of CUREs on STEM retention depends on demographic identities." The dataset comprises csv files with results from student surveys given to students enrolled in Biology 173 from Fall 2015 through Fall 2019 as well as institutional data of their course grades and cumulative GPA at the time they enrolled in Biology 173, and graduation and major data for student who had graduated by 2021. The survey questions used in the analysis and the IRB consent form are also included as pdfs.
- Keyword:
- undergraduate research, STEM retention, CURE, introductory biology laboratory, and education research
- Citation to related publication:
- Bradshaw, L., Vernon J., Schmidt T., James T., Zhang J., Archbold H., Cadigan K., Wolfe J.P. & Goldberg D. 2023. Research article: Influence of CUREs on STEM retention depends on demographic identities. J Microbiol Biol Educ (accepted)
- Discipline:
- Science
-
Resources for Training Machine Learning Algorithms Using CAM6 Simple Physics Packages
User Collection
- Creator:
- Limon, Garrett
- Description:
- The collection contains the code and the data used to train machine learning algorithms to emulate simplified physical parameterizations within the Community Atmosphere Model (CAM6). CAM6 is the atmospheric general circulation model (GCM) within the Community Earth System Model (CESM) framework, developed by the National Center for Atmospheric Research (NCAR). GCMs are made up of a dynamical core, responsible for the geophysical fluid flow calculations, and physical parameterization schemes, which estimate various unresolved processes. Simple physics schemes were used to train both random forests and neural networks in the interest of exploring the feasibility of machine learning techniques being used in conjunction with the dynamical core for improved efficiency of future climate and weather models. The results of the research show that various physical forcing tendencies and precipitation rates can be effectively emulated by the machine learning models.
- Keyword:
- Machine Learning, Climate Modeling, and Physics Emulators
- Discipline:
- Science and Engineering
2Works -
- Creator:
- Salaree, Amir, Spica, Zack, and Huang, Yihe
- Description:
- The items in this bundle are supporting videos to a study of subsea seismo-acoustics carried out regarding an earthquake in the Persian Gulf. The main data used in the study is a diver's recording of the acoustic waves from the earthquake. The epicenter and topography data used in this study are publicly available as cited in the README.txt file.
- Keyword:
- Seismo-acoustics, Persian Gulf, Divers’ Microphones, Seismic Hazard, Early Warning
- Discipline:
- Science
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- Creator:
- Limon, Garrett C.
- Description:
- The work guides the processing of CAM6 data for use in machine learning applications. We also provide workflow scripts for training both random forests and neural networks to emulate physic s schemes from the data, as well as analysis scripts written in both Python and NCL in order to process our results.
- 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 [Pre Print]. ESSOAr. https://10.1002/essoar.10512353.1
- Discipline:
- Engineering and Science
-
- Creator:
- University of Michigan Museum of Paleontology and CTEES
- Description:
- Reconstructed CT slices for Right innominate (acetabulum region) of Remingtonocetus domandaensis (University of Michigan Museum of Paleontology catalog number GSP-UM 3408) 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, Remingtonocetidae, UMMP, University of Michigan Museum of Paleontology, Eocene, and Geological Survey of Pakistan (GSP)
- Discipline:
- Science
-
- Creator:
- University of Michigan Museum of Paleontology and CTEES
- Description:
- Reconstructed CT slices for phalanx (pathological) of phytosaur (University of Michigan Museum of Paleontology catalog number UMMP VP 13838) 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, Phytosauria, UMMP, University of Michigan Museum of Paleontology, Triassic, and e06c6866-4cba-4532-2a68-d8e3357a674e
- Discipline:
- Science
-
- Creator:
- Lehman John T
- Description:
- Data were collected while developing a management plan for eliminating nuisance algal blooms in a chain of reservoirs along the Huron River in southeastern Michigan. Federal funding was provided by both the U.S. EPA and the USDA. The river-reservoir system is used for municipal drinking water, wastewater disposal, irrigation, industrial processes, hydroelectric generation, sport fishing, and recreation. The impoundments episodically developed surface scums of cyanobacteria, contained microcystin toxins, and emitted foul odors including hydrogen sulfide. Past management strategy had focused on external phosphorus loading but failed to prevent nuisance conditions. Data collection and analysis pointed to the overwhelming role of internal nutrient loading and resulted in a series of whole lake experiments that destratified Ford Lake during summer and eliminated the nuisance conditions.
- Keyword:
- Eutrophication, Limnology, and Nuisance Algae
- Citation to related publication:
- Ferris JA, Lehman JT. 2007. Interannual variation in diatom bloom dynamics: roles of hydrology, nutrient limitation, sinking, and whole lake manipulation. Water Res. 41:2551-2562., Ferris JA, Lehman JT. 2008. Nutrient budgets and river impoundments: Interannual variation and implications for detecting future changes. Lake Reserv Manage. 24:273-281., Goldenberg SZ, Lehman JT. 2012. Diatom response to the whole lake manipulation of a eutrophic urban impoundment. Hydrobiologia 691:71-80., Lehman EM, McDonald KE, Lehman JT. 2009. Whole lake selective withdrawal experiment to control harmful cyanobacteria in an urban impoundment. Water Res. 43:1187-1198., Lehman JT, Ferris JA, Platte RA. 2007. Role of hydrology in development of a vernal clear water phase in an urban impoundment. Freshwater Biol. 52:1773-1781., Lehman JT, Bell DW, McDonald KE. 2009. Reduced river phosphorus following implementation of a lawn fertilizer ordinance. Lake Reserv Manage. 25:307-312., Lehman JT. 2011. Nuisance cyanobacteria in an urbanized impoundment: Interacting internal phosphorus loading, nitrogen metabolism, and polymixis. Hydrobiologia 611:277-287., Lehman JT, Bell DW, Doubek JP, McDonald KE. 2011. Reduced additions to river phosphorus for three years following implementation of a lawn fertilizer ordinance. Lake Reserv Manage. 27:390-397. , Lehman JT, Doubek JP, Jackson EW. 2013. Effect of reducing allochthonous P load on alkaline phosphatase activity of phytoplankton in an urbanized watershed, SE Michigan, U.S.A. Lake Reserv Manage. 29:116-125., Lehman JT 2014. Understanding the role of induced mixing for management of nuisance algal blooms in an urbanized reservoir. Lake Reserv Manage. 30:1-9., and McDonald KE, Lehman JT. 2013. Dynamics of Aphanizomenon and Microcystis (cyanobacteria) during experimental manipulation of an urban impoundment. Lake Reserv Manage. 29:103-115.
- Discipline:
- Science
-
- Creator:
- McCuen, Brett A.
- Description:
- We present a comprehensive statistical analysis of high-frequency transient-large-amplitude (TLA) magnetic perturbation events that occurred at 12 high-latitude ground magnetometer stations throughout solar cycle 24 from 2009 to 2019. TLA signatures are defined as one or more second-timescale dB/dt interval with magnitude ≥ 6 nT/s within an hour event window. This study characterizes high-frequency TLA events based on their spatial and temporal behavior as well as relation to auroral substorms, geomagnetic storm phases and nighttime geomagnetic disturbance events events (GMD). We show that TLA events occur primarily at nighttime and solely in the high-latitude region above 60 degrees geomagnetic latitude. The largest TLA events occurred more often in the declining phase of the solar cycle when solar wind velocity was higher and ring current activity was lower, suggesting association to high-speed flows caused by coronal holes and subsequent corotating interaction regions reaching Earth. TLA perturbations often occurred preceding or within the most extreme nighttime geomagnetic disturbance (GMD) events with 5-10 minute timescales, but the TLA intervals were often even more localized than the ~300 km effective radius of GMDs: occurring at only some of the stations at which GMDs occurred. We show that TLA-related GMD events can result from dipolarization fronts in the magnetotail and fast flows toward Earth and are closely temporally associated to poleward boundary intensifications (PBI) and auroral streamers. The highly localized behavior and connection to the most extreme GMD events suggests that TLA intervals are a ground manifestation of the features within rapid and complex ionospheric structures that can drive GICs.
- Keyword:
- geomagnetic field, high frequency, space weather, transient-large-amplitude, TLA, high frequency dB/dt, dB/dt search algorithm
- Citation to related publication:
- McCuen, B. A., Moldwin, M. B., Engebretson, M. J., Weygand, J. G., Nishimura, Y. (2023). A Statistical Analysis of High-frequency Transient-Large-Amplitude Geomagnetic Disturbance. [To be submitted to] Journal of Geophysical Research: Space Physics
- Discipline:
- Science
-
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