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  • Data in support of the study "Modeled Response of Greenland Snowmelt to the Presence of Biomass Burning-Based Absorbing Aerosols in the Atmosphere and Snow"

    Work
    Creator: Ward, Jamie L., Flanner, Mark G., Bergin, Mike, Dibb, Jack E., Polashenski, Chris M., Soja, Amber J., Thomas, Jennie L.
    Description: Biomass burning produces smoke aerosols that are emitted into the atmosphere. Some smoke constituents, notably black carbon (BC), are highly effective light-absorbing aerosols (LAA). Emitted LAA can be transported to high albedo regions like the Greenland Ice Sheet (GrIS) and affect local snowmelt. In the summer, the effects of LAA in Greenland are uncertain. To explore how LAA affect GrIS snowmelt and surface energy flux in the summer, we conduct idealized global climate model simulations with perturbed aerosol amounts and properties in the GrIS snow and overlying atmosphere. The in-snow and atmospheric aerosol burdens we select range from background values measured on the GrIS to unrealistically high values. This helps us explore the linearity of snowmelt response and to achieve high signal-to-noise ratios. With LAA operating only in the atmosphere, we find no significant change in snowmelt due to the competing effects of surface dimming and tropospheric warming. Regardless of atmospheric LAA presence, in-snow BC-equivalent mixing ratios greater than ~60 ng/g produce statistically significant snowmelt increases over much of the GrIS. We find that net surface energy flux changes correspond well to snowmelt changes for all cases. The dominant component of surface energy flux change is solar energy flux, but sensible and longwave energy fluxes respond to temperature changes. Atmospheric LAA dampen the magnitude of solar radiation absorbed by in-snow LAA when both varieties are simulated. In general, the significant melt and surface energy flux changes we simulate occur with LAA quantities that have never been recorded in Greenland.
  • X-ray tomography dataset for 'Caught in the act: The mechanism of eutectic modification by trace impurities'

    Work
    Creator: Moniri, Saman, Xiao, Xianghui, and Shahani, Ashwin J.
    Description: The data file is comprised of 22,500 X-ray projections (15 scans of 1500 projections each) recorded during solidification of Al-Ge-Na. The raw data file is in .hdf format and can be reconstructed into .tiff, e.g., by using the TomoPy toolbox in Python.
  • Supporting data and scripts for the paper "Variability in the location of High Frequency Oscillations during prolonged intracranial EEG recordings"

    Work
    Creator: Gliske, Stephen V and Stacey, William C
    Description: This data is part of a large program to translate detection and interpretation of HFOs into clinical use. A zip file is included which contains hfo detections, metadata, and Matlab scripts. The matlab scripts analyze this input data and produce figures as in the referenced paper (note: the blind source separation method is stochastic, and so the figures may not be exactly the same). A file "README.txt" provides more detail about each individual file within the zip file.
  • Maternal and Infant Survival Study (MISS) Interviews with Health Care Providers in Ghana about Neonatal Near-Misses

    Work
    Creator: Moyer, Cheryl A
    Description: Data reflect the knowledge, attitudes, and beliefs of health care providers regarding neonatal near-misses in Neonatal Intensive Care Units (NICUs) in southern Ghana.
  • Effective Fetch and Relative Exposure Index Maps for the Laurentian Great Lakes

    Work
    Creator: Mason, Lacey A., Riseng, Catherine M., Layman, Andrew J., and Jensen, Robert
    Description: Wind exposure is a key physical driver of coastal systems in aquatic environments influencing circulation and wave dynamics. A measure of wind exposure is fetch, the distance over which wind can travel across open water. In large lake systems, such as the Laurentian Great Lakes, estimating fetch has proved to be difficult due to their vast size and complex topobathymetry. Here we describe the development of two spatially discrete indicators of exposure to provide a more accurate indicator of influence of wind exposure in the nearshore of the Laurentian Great Lakes. We summarized wind data from offshore buoys and leveraged existing tools to calculate effective fetch and relative exposure index (effective fetch scaled by mean wind speed) at a 30 m grid cell resolution. We validated these models by comparing our exposure maps to the U.S. Army Corps of Engineers Wave Information Studies models and found general agreement. These exposure maps are available for public download for the years 2004-2014.
  • Designing Future Employment Applications for Underserved Job Seekers: A Speed Dating Study

    Work
    Creator: Dillahunt, Tawanna R., Lam, Jason, Lu, Alex, and Wheeler, Earnest
    Description: Today’s Information and Communication Technologies (ICTs) support job searches, resume creation and the ability to highlight employment skills on social media. However, these technological tools are often tailored to high-income, highly educated users, and white-collar professionals. It is unclear what interventions address the needs of job seekers who have limited resources, education, or who may be underserved in other ways. We gathered insights from past literature and generated ten tangible design concepts to address the needs of underserved job seekers. We then conducted a needs validation and speed dating study to understand which concepts were most viable among our population. We found that the three most preferred concepts immediately addressed job seekers’ most practical needs. and Per reviewer feedback, we aim to improve the utility of this publication to other scholars by including our research materials here. This dataset includes the interview script, storyboards that were used in the needs validation study, the demographics survey/questionnaire, and the consent form.
  • Event List for "Interchange Injections at Saturn: Statistical Survey of Energetic H+ Sudden Flux Intensifications"

    Work
    Creator: Azari, A. R.
    Description: ABSTRACT: We present a statistical study of interchange injections in Saturn's inner and middle magnetosphere focusing on the dependence of occurrence rate and properties on radial distance, partial pressure, and local time distribution. Events are evaluated from over the entirety of the Cassini mission’s equatorial orbits between 2005 and 2016. We identified interchange events from CHarge Energy Mass Spectrometer (CHEMS) H+ data using a trained and tested automated algorithm, which has been compared with manual event identification for optimization. We provide estimates of interchange based on intensity, which we use to investigate current inconsistencies in local time occurrence rates. This represents the first automated detection method of interchange, estimation of injection event intensity, and comparison between interchange injection survey results. We find the peak rates of interchange occur between 7 - 9 Saturn radii and that this range coincides with the most intense events as defined by H+ partial particle pressure. We determine that nightside occurrence dominates as compared to the dayside injection rate, supporting the hypothesis of an inversely dependent instability growth rate on local Pedersen ionospheric conductivity. Additionally, we observe a slight preference for intense events on the dawn side, supporting a triggering mechanism related to large-scale injections from downtail reconnection. Our observed local time dependence paints a dynamic picture of interchange triggering due to both the large-scale injection driven process and ionospheric conductivity. Within this repository we provide a readme file (description of data file and usage) and the event list provided as a .txt file. The event list includes start and stop times, comparison to previous surveys, and the average location of events identified. Additional formats are available on request. and Further details on this method can be found in "Interchange Injections at Saturn: Statistical Survey of Energetic H+ Sudden Flux Intensifications" by Azari et al., 2018 in the Journal of Geophysical Research: Space Physics. https://doi.org/10.1029/2018JA025391.
  • Bayesian Population Correlation: A probabilistic approach to comparing detrital zircon age distributions

    Work
    Creator: Tye, Alexander R, Wolf, Aaron S, and Niemi, Nathan A
    Description: Detrital zircon age distributions provide robust insights into past sedimentary systems, but these age distributions are often complex and multi-peaked, with sample sizes too small to confidently resolve population distributions. This limited sampling hinders existing quantitative methods for comparing detrital zircon age distributions, which show systematic dependence on the sizes of compared samples. The proliferation of detrital zircon studies motivates the development of more robust quantitative methods. We present the first attempt, to our knowledge, to infer probability model ensembles (PMEs) for samples of detrital zircon ages using a Bayesian method. Our method infers the parent population age distribution from which a sample is drawn, using a Monte Carlo approach to aggregate a representative set of probability models that is consistent with the constraints that the sample data provide. Using the PMEs inferred from sample data, we develop a new estimate of correspondence between detrital zircon populations called Bayesian Population Correlation (BPC). Tests of BPC on synthetic and real detrital zircon age data show that it is nearly independent from sample size bias, unlike existing correspondence metrics. Robust BPC uncertainties can be readily estimated, enhancing interpretive value. When comparing two partially overlapping zircon age populations where the shared proportion of each population is independently varied, BPC results conform almost perfectly to expected values derived analytically from probability theory. This conformity of experimental and analytical results permits direct inference of the shared proportions of two detrital zircon age populations from BPC. We provide MATLAB scripts to facilitate the procedures we describe.
  • Model results for "Modeling study of geospace system response to the solar wind dynamic pressure enhancement on March 17, 2015"

    Work
    Creator: Ozturk, Dogacan
    Description: The global magnetosphere-ionosphere-thermosphere (M-I-T) system is intrinsically coupled and susceptible to external drivers such as solar wind dynamic pressure enhancements. In order to understand the large-scale dynamic processes in the M-I-T system due to the compression from the solar wind, the 17 March 2015 sudden commencement was studied in detail using global numerical models. This data set is comprised of the simulation data generated from these models. and NOTE: The following changes were made to this dataset on March 28, 2018. First, two mp4 files were added. Second, the symbol representing "degree" was not rendering properly in the README file. The symbols were removed and replaced with the word "degree". Third, the metadata in the "methodology" and "description" fields were revised for content and clarity. On April 16, 2018 a citation to the corresponding article was added to the metadata record.
  • Low-Fe(III) Greenalite Was a Primary Mineral from Neoarchean Oceans (Raw Data)

    Work
    Creator: Johnson, Jena E.
    Description: Note: The "Readme_Metadata" file was updated on March 15, 2018 to include a citation to the related article making use of this data and was reformatted to be presented as a pdf file rather than as a docx file. and This data set is comprised of synchrotron-based X-ray transmission and absorption spectroscopy data as well as X-ray diffraction patterns that were performed to characterize the best-preserved examples of nanoscale iron silicate mineral inclusions from 2.5 billion-year-old Banded Iron Formations (BIFs) and ferruginous cherts.