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![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Creator:
- Garrett, Tim
- Owner:
- BRIAN MCBRIDE
- Language:
- English
- Date Uploaded:
- 07/10/2019
- Date Modified:
- 07/30/2019
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S5CV4FWW
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Description:
- Thin boundary layer Arctic mixed-phase clouds are generally thought to precipitate pristine and aggregate ice crystals. Here we present automated surface photographic measurements showing that only 35\% of precipitation particles exhibit negligible riming and that graupel particles $\geq1\,\rm{mm}$ in diameter commonly fall from clouds with liquid water paths less than $50\,\rm{g\,m^{-2}}$. A simple analytical formulation predicts that significant riming enhancement can occur in updrafts with speeds typical of Arctic clouds, and observations show that such conditions are favored by weak temperature inversions and strong radiative cooling at cloud top. However, numerical simulations suggest that a mean updraft speed of $0.75\,\rm{m\,s^{-1}}$ would need to be sustained for over one hour. Graupel can efficiently remove moisture and aerosols from the boundary layer. The causes and impacts of Arctic riming enhancement remain to be determined.
- Subject:
- Atmospheric sciences, Computational research, and Arctic research
- Creator:
- Garrett, Timothy J. and Fitch, Kyle E.
- Contributor:
- Shkurko, Konstantin , Talaei, Ahmad, Gaustad, Krista, and Maahn, Maximilian
- Owner:
- BRIAN MCBRIDE
- Based Near Label Tesim:
- Oliktok Point, Alaska, United States
- Language:
- English
- Date Uploaded:
- 06/04/2020
- Date Modified:
- 07/21/2020
- Date Created:
- Code creation dates from 20161208 to 20180609 and Processed between 20170627 and 20190320
- Resource Type:
- Software or Program Code and Dataset
- Identifier:
- https://doi.org/10.7278/s50dva5jk2pd
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Description:
- We consider a scenario where the small satellites of Pluto and Charon grew within a disk of debris from an impact between Charon and a trans-Neptunian object (TNO). After Charon's orbital motion boosts the debris into a disk-like structure, rapid orbital damping of meter-sized or smaller objects is essential to prevent the subsequent reaccretion or dynamical ejection by the binary. From analytical estimates and simulations of disk evolution, we estimate an impactor radius of 30-100 km; smaller (larger) radii apply to an oblique (direct) impact. Although collisions between large TNOs and Charon are unlikely today, they were relatively common within the first 0.1-1 Gyr of the solar system. Compared to models where the small satellites agglomerate in the debris left over by the giant impact that produced the Pluto-Charon binary planet, satellite formation from a later impact on Charon avoids the destabilizing resonances that sweep past the satellites during the early orbital expansion of the binary.
- Subject:
- Astrophysics
- Creator:
- Kenyon, Scott and Bromley, Benjamin
- Owner:
- BENJAMIN BROMLEY
- Date Uploaded:
- 08/03/2020
- Date Modified:
- 08/14/2020
- Date Created:
- 20191115 to 20200220
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50D5Q2MFDBT
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Description:
- This study investigates impacts of altering subgrid-scale mixing in “convection-permitting” km-scale horizontal grid spacing (∆h) simulations by applying either constant or stochastic multiplicative factors to the horizontal mixing coefficients within the Weather Research and Forecasting model. In quasi-idealized 1-km ∆h simulations of two observationally based squall line cases, constant enhanced mixing produces larger updraft cores that are more dilute at upper levels, weakens the cold pool, rear inflow jet, and front-to-rear flow of the squall line, and degrades the model’s effective resolution. Reducing mixing by a constant multiplicative factor has the opposite effect on all metrics. Completely turning off parameterized horizontal mixing produces bulk updraft statistics and squall line mesoscale structure closest to a LES “benchmark” among all 1-km simulations, although the updraft cores are too undilute. The stochastic mixing scheme, which applies a multiplicative factor to the mixing coefficients that varies stochastically in time and space, is employed at 0.5-, 1-, and 2-km ∆h. It generally reduces mid-level vertical velocities and enhances upper-level vertical velocities compared to simulations using the standard mixing scheme, with more substantial impacts at 1-km and 2-km ∆h compared to 0.5-km. The stochastic scheme also increases updraft dilution to better agree with the LES for one case, but has less impact on the other case. Stochastic mixing acts to weaken the cold pool but without a significant impact on squall line propagation. It also does not affect the model’s overall effective resolution unlike applying constant multiplicative factors to the mixing coefficients.
- Subject:
- Atmospheric Sciences
- Creator:
- Stanford, McKenna, Morrison, Hugh, and Varble, Adam
- Owner:
- MCKENNA STANFORD
- Language:
- English
- Date Uploaded:
- 08/17/2020
- Date Modified:
- 10/27/2020
- Date Created:
- 20190301 - 20200430
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50DJNGQ6V67
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Description:
- We analyzed 4,754 broadband seismic recordings of the SKS, SKKS, and SPdKS wavefield from 13 high quality events sampling the Samoa ultralow-velocity zone (ULVZ). We measured differential travel-times and amplitudes between the SKKS and SKS arrivals, which are highly sensitive to the emergence of the SPdKS seismic phase, which is in turn highly sensitive to lowermost mantle velocity perturbations such as generated by ULVZs. We modeled these data using a 2-D axi-symmetric waveform modeling approach and are able to explain these data with a single ULVZ. In order to predict both travel-time and amplitude perturbations we found that a large ULVZ length in the great circle arc direction on the order of 10° or larger is required. The large ULVZ length limits acceptable ULVZ elastic parameters. Here we find that δVS and δVP reductions from 20% to 22% and 15% to 17% respectively gives us the best fit, with a thickness of 26 km. Initial 3-D modeling efforts do not recover the extremes in the differential measurements, demonstrating that 3-D effects are important and must be considered in the future. However, the 3-D modeling is generally consistent with the velocity reductions recovered with the 2-D modeling. These velocity reductions are compatible with a compositional component to the ULVZ. Furthermore, geodynamic predictions for a compositional ULVZ that is moving predict a long linear shape similar to the shape of the Samoa ULVZ we confirm in this study. and This collection includes radial component displacement seismograms in the time window including the SKS, SKKS and SPdKS seismic arrivals. These data all interact with the Samoa ultra-low velocity zone at the core-mantle boundary. All data used in the study of Krier et al., 2021 (JGR) is included in this collection.
- Subject:
- Geology, seismology, and Geophysics
- Creator:
- Michael S. Thorne, Tarje Nissen-Meyer, Justin D. Krier, and Kuangdai Leng
- Owner:
- Michael Thorne
- Based Near Label Tesim:
- Tonga Trench, , Tonga
- Language:
- English
- Date Uploaded:
- 02/17/2021
- Date Modified:
- 12/09/2021
- Date Created:
- January 2019 to January 2020
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50DT3X22GGB
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Description:
- Using a suite of numerical calculations, we consider the long-term evolution of circumbinary debris from the Pluto--Charon giant impact. Initially, these solids have large eccentricity and pericenters near Charon's orbit. On time scales of 100--1000 yr, dynamical interactions with Pluto and Charon lead to the ejection of most solids from the system. As the dynamics moves particles away from the barycenter, collisional damping reduces the orbital eccentricity of many particles. These solids populate a circumbinary disk in the Pluto-Charon orbital plane; a large fraction of this material lies within a `satellite zone' that encompasses the orbits of Styx, Nix, Kerberos, and Hydra. Compared to the narrow rings generated from the debris of a collision between a trans-Neptunian object (TNO) and Charon, disks produced after the giant impact are much more extended and may be a less promising option for producing small circumbinary satellites.
- Subject:
- Astronomy
- Creator:
- Bromley, Benjamin and Kenyon, Scott
- Owner:
- BENJAMIN BROMLEY
- Language:
- English
- Date Uploaded:
- 02/03/2021
- Date Modified:
- 12/09/2021
- Date Created:
- 20191115 to 20200220
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50DSSMBHHXN
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Description:
- Objective: In 2018, the Network of the National Libraries of Medicine (NNLM) launched a national sponsorship program to support U.S. public library staff in completing the Medical Library Association’s (MLA) Consumer Health Information Specialization (CHIS). The primary objective of this research project was to determine if completion of the sponsored specialization was successful in improving public library staff ability to provide consumer health information and whether it resulted in new services, programming, or outreach activities at public libraries. Secondary objectives of this research were to determine motivation for and benefits of the specialization and to determine the impact on sponsorship on obtaining and continuing the specialization. Methods: To evaluate the sponsorship program, we developed and administered a 16-question online survey via REDCap in August 2019 to 224 public library staff that were sponsored during the first year of the program. We measured confidence and competence in providing consumer health information using questions aligned with the eight Core Competencies for Providing Consumer Health Information Services [1]. Additionally, the survey included questions about new consumer health information activities at public libraries, public library staff motivation to obtain the specialization, and whether it led to immediate career gains. To determine the overall value of the NNLM sponsorship, we measured whether funding made it more likely for participants to complete or continue the specialization. Results: Overall, 136 participants (61%) responded to the survey. Our findings indicated that the program was a success: over 80% of participants reported an increase in core consumer health competencies, with a statistically significant improvement in mean competency scores after completing the specialization. Ninety percent of participants have continued their engagement with NNLM, and over half offered new health information programs and services at their public library. All respondents indicated that completing the specialization met their expectations, but few reported immediate career gains. While over half of participants planned to renew the specialization or obtain the more advanced, Level II specialization, 72% indicated they would not continue without the NNLM sponsorship. Conclusion: Findings indicate that NNLM sponsorship of the CHIS specialization was successful in increasing the ability of public library staff to provide health information to their community. and This dataset represents the de-identified raw results of a 16-question, online survey (via REDCap) collected in August 2019 to 224 public library staff who were sponsored for a Consumer Health Information Specialization (CHIS). The purpose of the study was to determine whether the sponsorship program had an impact on public library staff to provide consumer health information.
- Subject:
- Interprofessional Relations, Information Services, Professional Competence, Librarians / education, Libraries, Libraries, Medical , Consumer Health Information, and Humans
- Creator:
- Lake, Erica, Wolfe, Susan M, Knapp, Molly , Spatz, Michele, and Kiscaden, Elizabeth
- Owner:
- Molly Knapp
- Based Near Label Tesim:
- United States, , United States
- Language:
- English
- Date Uploaded:
- 11/12/2020
- Date Modified:
- 02/05/2021
- Date Created:
- August 2019
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50D1DAY2QQQ
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Description:
- Background. Common cold viruses create significant health and financial burdens, and understanding key loci of transmission would help focus control strategies. This study (1) examines factors that influence when individuals transition from a negative to positive test (acquisition) or a positive to negative test (loss) of rhinovirus (HRV) and other respiratory tract viruses in 26 households followed weekly for one year, (2) investigates evidence for intrahousehold and interhousehold transmission and the characteristics of individuals implicated in transmission, and (3) builds data-based simulation models to identify factors that most strongly affect patterns of prevalence. Methods. We detected HRV, coronavirus, paramyxovirus, influenza and bocavirus with the FilmArray polymerase chain reaction (PCR) platform (BioFire Diagnostics, LLC). We used logistic regression to find covariates affecting acquisition or loss of HRV including demographic characteristics of individuals, their household, their current infection status, and prevalence within their household and across the population. We apply generalized linear mixed models to test robustness of results. Results. Acquisition of HRV was less probable in older individuals and those infected with a coronavirus, and higher with a higher proportion of other household members infected. Loss of HRV is reduced with a higher proportion of other household members infected. Within households, only children and symptomatic individuals show evidence for transmission, while between households only a higher number of infected older children (ages 5-19) increases the probability of acquisition. Coronaviruses, paramyxoviruses and bocavirus also show evidence of intrahousehold transmission. Simulations show that age-dependent susceptibility and transmission have the largest effects on mean HRV prevalence. Conclusions. Children are most likely to acquire and most likely to transmit HRV both within and between households, with infectiousness concentrated in symptomatic children. Simulations predict that the spread of HRV and other respiratory tract viruses can be reduced but not eliminated by practices within the home.
- Creator:
- Adler, Frederick R.
- Contributor:
- Ampofo, Krow, Pavia, Andrew, and Byington, Carrie L.
- Owner:
- BRIAN MCBRIDE
- Based Near Label Tesim:
- Salt Lake City, Utah, United States
- Language:
- English
- Date Uploaded:
- 07/10/2019
- Date Modified:
- 12/09/2021
- Date Created:
- August 2009 - August 2010
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S5XG9P97
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Description:
- The Andes Cordillera, which runs the length of South America and rises up to 5,000 m MSL within 200 km of the Pacific coast, dramatically influences the distribution of winter precipitation and snowpack over Chile and Argentina. The study of orographic precipitation processes, particularly along the western slopes of the Andes, is important to improve forecasts of severe flooding and snowpack in a region that depends on snowmelt for water resources. While orographic effects have been investigated on synoptic scales in the Andes, the lack of operational radar coverage and high-elevation, long-term precipitation records have, before the present study, precluded an in-depth investigation into the mesoscale and microphysical processes that affect the distribution of precipitation in the region. This dataset was collected during the Chilean Orographic and Mesoscale Precipitation Study (ChOMPS), which, from May-October 2016, investigated the evolution of precipitation amounts, dropsize distribution, and the vertical profile of radar echoes along an east-west transect that stretched from the Pacific coast to the windward slope of the Andes. The transect, at ~36°S, was made up of a coastal site upstream of the coastal mountain range (Concepción), a central valley site (Chillán), and a mountain site (Las Trancas). Instrumentation along the transect included three vertically pointing Micro-Rain-Radars, two Parsivel Disdrometers, and several meteorological stations. The dataset documents the evolution of Doppler velocity and reflectivity profiles with inland extent during early, middle, and late storm sectors. Additionally, the transect provides a season-long record of the inland evolution of melting layer height as well as the prevalence and structure of shallow non-brightband rain and the characteristics of its inland penetration to the central valley. This dataset, the first of its kind in the Chilean Andes, provides unique insight into mesoscale and orographic precipitation processes that also have applicability to the west coast of the United States and other mountainous regions.
- Subject:
- Meteorology
- Creator:
- Campbell, Leah S., Minder, Justin, and Garreaud, Rene
- Contributor:
- Steenburgh, Jim, Rojas, Yazmina, Viscarra, Also, Montecinos, Aldo, Veloso, Daniel Sebastian, and Salazar, Diego Rivera
- Owner:
- Leahs Campbell
- Based Near Label Tesim:
- Chile, , Chile
- Language:
- English
- Date Uploaded:
- 05/16/2020
- Date Modified:
- 12/09/2021
- Date Created:
- May 15 2016 - October 7 2016
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/doi:10.7278/S50DJXEW0JH3
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Description:
- The dynamic properties of freestanding rock landforms are a function of fundamental material and mechanical parameters, facilitating non-invasive vibration-based structural assessment. Characterization of resonant frequencies, mode shapes, and damping ratios, however, can be challenging at culturally-sensitive geologic features, such as rock arches, where physical access is limited. Using sparse ambient vibration measurements, we describe three resonant modes between 1 and 40 Hz for 17 natural arches in Utah spanning a range of lengths from 3 – 88 m. Modal polarization data are evaluated to combine field observations with 3-D numerical models. We find outcrop-scale elastic moduli vary from 0.8 to 8.0 GPa, correlated with diagenetic processes, and identify low damping at all sites. Dense-array cross-correlation results from an additional arch validate predictions of simple bending modes and fixed boundary conditions. Our results establish use of sparse ambient resonance measurements for structural assessment and monitoring of arches and similar freestanding geologic features.
- Subject:
- geological engineering
- Creator:
- Finnegan, Riley, Moore, Jeffrey R, and Geimer, Paul R
- Owner:
- Paul Geimer
- Based Near Label Tesim:
- Utah, Utah, United States
- Language:
- English
- Date Uploaded:
- 01/13/2020
- Date Modified:
- 12/09/2021
- Date Created:
- 2015-2019
- Resource Type:
- Dataset