Physical Sciences and Mathematics Commons^™

Nalidarturbopauseshear, Titus Yuan

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The USU Na lidar has been upgraded to be able to measure temperature and winds in the lower thermosphere up to ~ 115 km routinely. The new capability, coupled with the existing nightglow instruments at USU, enables the investigation of the extreme large wind and shears in this region and their correlation to the atmospheric gravity waves activities in the upper mesosphere.

Tdim Ionospheric Model Tec Maps Of The High-Latitude Northern Hemisphere, Used In The Paper Titled "Hemispherical Shifted Symmetry In Polar Cap F-Region Patch Occurrence: A Survey Of Gps Tec Data From 2015 To 2018", Michael David, Jan J. Sojka

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TDIM ionospheric model was run for the year 2018 at 10-day intervals and 2-hr intervals in UT.

Data From Analysis Of Mesosphere Secular Trends And Episodic Variability, 9/3/1993 To 8/5/2003, Troy A. Wynn, Vincent B. Wickwar, Joshua P. Herron

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The database examined here covers a time span from September 1993 to August 2003 and an altitude range of 45 to 90 km, and contains 593 nightly temperature profiles. We examine our data for secular warming and cooling and decadal scale (solar cycle) variations by applying three different models to the data.

Usu-Csu Na Lidar Data, Tao Yuan

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The naturally existing mesospheric Na layer, overlapping the upper mesosphere and lower thermosphere, provides an excellent tracer for lidar remote sensing. The Na Doppler lidar technique is designed to measure neutral temperature and wind profiles in the mesopause region (~ 80-110 km) by observing the thermal broadening and Doppler shift of the atomic Na fluorescence spectrum. Relocated from Colorado State University (CSU), the Na lidar at Utah State University (USU) has been operating since the summer of 2010, for roughly 1000 hours per year. Enabled by a pair of Faraday filters, it has a unique daytime observation capability to study …

Data From: Polar Topside Ionosphere During Geomagnetic Storms: Comparison Of Isis-Ii With Tdim, Jan J. Sojka, Dan Rice, Michael David, Robert W. Schunk, Robert Benson, H. G. James

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Output files from runs of the TDIM ionospheric model used for calculations and electron density profiles from ISIS-II and TDIM used in figures in the article in Radio Science.

Mesospheric Densities And Temperatures Derived From 11 Years Of Data Acquired With The Rayleigh-Scatter Lidar At The Atmospheric Lidar Observatory At Utah State University, Vincent B. Wickwar, Joshua P. Herron

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Frequent observations were carried out with the Rayleigh-scatter lidar at Utah State University’s Atmospheric Lidar Observatory (41.742572° N, 111.808273° W, and 1466 m) from August 1993 through December 2004. Of 964 nights observed, a total of 839 nights were judged good for deriving temperatures. These 839 were reduced to obtain all-night relative neutral densities and absolute temperatures. These results extend from 45 to ≤ 95 km, thereby covering the mesosphere. This netCDF file starts by giving the number of nights included in the file. For each night, the netCDF file then provides defining parameters and derived profiles, as defined below. …

Usu Rayleigh-Scatter Lidar 2014-2015 Nightly Temperatures, Leda Sox, Vincent B. Wickwar, Tao Yuan

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Temperatures from a collocated Rayleigh-scatter lidar (RSL) and sodium resonance lidar were compared night-by-night, at different altitude levels, and hour-by-hour.

Three zipped files are provided.

USU RSL 2014-2015 [O] Corrected Temperatures.zip contains 36 files, one per night and hour, in RSLHourlyTemperaturesYYYYMMDDhour#.txt filename format.

USU RSL 2014-2015 Hourly Temperatures.zip contains 36 files, one per night and hour, in RSLHourlyTemperaturesYYYYMMDDhour#.txt filename format.

USU RSL 2014-2015 Nightly Temperatures.zip contains 19 files, one per night, in RSLTemperaturesYYYYMMDD.txt filename format.

Automated Calibration Of Atmospheric Oxidized Mercury Measurements, Seth Lyman, Colleen Jones, Trevor O'Neil, Tanner Allen, Matthieu Miller, Mae Sexauer Gustin, Ashley M. Pierce, Winston Luke, Xinrong Ren, Paul Kelley

USU Uintah Basin Faculty Publications

The atmosphere is an important reservoir for mercury pollution, and understanding of oxidation processes is essential to elucidating the fate of atmospheric mercury. Several recent studies have shown that a low bias exists in a widely applied method for atmospheric oxidized mercury measurements. We developed an automated, permeation tube-based calibrator for elemental and oxidized mercury, and we integrated this calibrator with atmospheric mercury instrumentation (Tekran 2537/1130/1135 speciation systems) in Reno, Nevada and at Mauna Loa Observatory, Hawaii, U.S.A. While the calibrator has limitations, it was able to routinely inject stable amounts of HgCl2 and HgBr2 into atmospheric mercury measurement systems …

Modeling The Global Atmospheric Transport And Deposition Of Mercury To The Great Lakes, Mark D. Cohen, Roland R. Draxler, Richard S. Artz, Pierrette Blanchard, Mae Sexauer Gustin, Young-Ji Han, Thomas M. Holsen, Daniel A. Jaffe, Paul Kelley, Hang Lei, Christopher P. Loughner, Winston T. Luke, Seth N. Lyman, David Niemi, Jozef M. Pacyna, Martin Pilote, Laurier Poissant, Dominique Ratte, Xinrong Ren, Frits Steenhuisen, Alexandra Steffen, Rob Tordon, Simon J. Wilson

USU Uintah Basin Faculty Publications

Mercury contamination in the Great Lakes continues to have important public health and wildlife ecotoxicology impacts, and atmospheric deposition is a significant ongoing loading pathway. The objective of this study was to estimate the amount and source-attribution for atmospheric mercury deposition to each lake, information needed to prioritize amelioration efforts. A new global, Eulerian version of the HYSPLIT-Hg model was used to simulate the 2005 global atmospheric transport and deposition of mercury to the Great Lakes. In addition to the base case, 10 alternative model configurations were used to examine sensitivity to uncertainties in atmospheric mercury chemistry and surface exchange. …

Data From: How Uncertainty In The Neutral Wind Limits The Accuracy Of Ionospheric Modeling And Forecasting, Michael David, Jan Sojka, Robert W. Schunk

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Output files from runs of the TDIM ionospheric model used for the figures and calculations in the article in JGR Space Physics.

Progress On Understanding Atmospheric Mercury Hampered By Uncertain Measurements, Daniel A. Jaffe, Seth N. Lyman, Helen M. Amosl, Mae Sexauer Gustin, Jiaoyan Huang, Noelle E. Selin, Leonard Levin, Arnout Ter Schure, Robert P. Mason, Robert Talbot, Andrew Rutter, Brandon Finley, Lyatt Jaeglé, Viral Shah, Crystal Mcclure, Jesse Ambrose, Lynne Gratz, Steven Lindberg, Peter Weiss-Penzias, Guey-Rong Sheu, Dara Feddersen, Milena Horvat, Ashu Dastoor, Anthony J. Hynes, Huiting Mao, Jeroen E. Sonke, Franz Slemr, Jenny A. Fisher, Ralf Ebinghaus, Yanxu Zhang, Grant Edwards

USU Uintah Basin Faculty Publications

Mercury (Hg) is a potent neurotoxin and globally reducing environmental levels is seen as paramount for protecting human and wildlife health. In 2013, many countries finalized the negotiations on, and have now signed, the Minamata Convention on Mercury, which commits participating countries to reduce emissions and use of mercury. Successful implementation of the treaty will require adequate verification through global monitoring.

A Review Of Passive Sampling Systems For Ambient Air Mercury Measurements, Jiaoyan Huang, Seth N. Lyman, Jelena Stamenkovic Hartman, Mae Sexauer Gustin

USU Uintah Basin Faculty Publications

Atmospheric mercury (Hg) temporal and spatial patterns must be measured accurately in order to adequately understand the role of this pathway as it relates to Hg toxicity and exposure of humans and wildlife to Hg. It is also important to understand the distribution of the different chemical forms (elemental, oxidized, or particle bound) and specific compounds in air (e.g., HgCl2, HgBr2, HgO, Hg(NO3)2, and HgSO4). However, the current automated and passive sampling methods of measurement have limitations and artifacts impacting our ability to achieve this task. Both abiotic and biotic systems have been developed to measure the total gaseous Hg …

Development, Testing, And Deployment Of An Air Sampling Manifold For Spiking Elemental And Oxidized Mercury During The Reno Atmospheric Mercury Intercomparison Experiment (Ramix), B. D. Finley, D. A. Jaffe, K. Call, Seth Lyman, M. Sexauer Gustin, C. Peterson, M. Miller, T. Lyman

USU Uintah Basin Faculty Publications

The Reno Atmospheric Mercury Intercomparison Experiment (RAMIX) was in Reno, NV from August 22, 2011 to September 16, 2011. The goals of the experiment were to compare existing and new methods for measurements of ambient elemental and oxidized Hg, and to test these with quantitative spikes of Hg0, HgBr2, O3 and water vapor. In this paper we describe the design, testing, and deployment of a high flow manifold system designed to deliver ambient air and spiked compounds to multiple instruments simultaneously. The manifold was constructed of 1” OD PFA tubing and heated to 115 °C for the entire active zone. …

Fast Time Resolution Oxidized Mercury Measurements During The Reno Atmospheric Mercury Intercomparison Experiment (Ramix), Jesse L. Ambrose, Seth N. Lyman, Jiaoyan Huang, Mae Sexauer Gustin, Daneil A. Jaffe

USU Uintah Basin Faculty Publications

The Reno Atmospheric Mercury Intercomparison Experiment (RAMIX) was carried out from 22 August to 16 September, 2011 in Reno, NV to evaluate the performance of new and existing methods to measure atmospheric mercury (Hg). Measurements were made using a common sampling manifold to which controlled concentrations of Hg species, including gaseous elemental mercury (GEM) and HgBr2 (a surrogate gaseous oxidized mercury (GOM) compound), and potential interferents were added. We present an analysis of Hg measurements made using the University of Washington’s Detector for Oxidized Hg Species (DOHGS), focusing on tests of GEM and HgBr2 spike recovery, the potential for interference …

Do We Understand What The Mercury Speciation Instruments Are Actually Measuring? Results Of Ramix, Mae Sexauer Gustin, Jiaoyan Huang, Matthieu B. Miller, Christianna Peterson, Daniel A. Jaffe, Jesse Ambrose, Brandon D. Finley, Seth N. Lyman, Kevin Call, Robert Talbotl, Dara Feddersen, Huiting Mao, Steven E. Lindberg

USU Uintah Basin Faculty Publications

From August 22 to September 16, 2012, atmospheric mercury (Hg) was measured from a common manifold in the field during the Reno Atmospheric Mercury Intercomparison eXperiment. Data were collected using Tekran systems, laser induced fluorescence, and evolving new methods. The latter included the University of Washington-Detector for Oxidized Mercury, the University of Houston Mercury instrument, and a filter-based system under development by the University of Nevada-Reno. Good transmission of total Hg was found for the manifold. However, despite application of standard protocols and rigorous quality control, systematic differences in operationally defined forms of Hg were measured by the sampling systems. …

Development Of A Passive Sampler For Gaseous Mercury, Mae S. Gustin, Seth N. Lyman, P. Kilner, E. Prestbo

USU Uintah Basin Faculty Publications

Here we describe work toward development of the components of a cost effective passive sampling system for gaseous Hg that could be broadly deployed by nontechnical staff. The passive sampling system included an external shield to reduce turbulence and exposure to precipitation and dust, a diffusive housing that directly protects the collection surface during deployment and handling, and a collection surface. A protocol for cleaning and deploying the sampler and an analytical method were developed. Our final design consisted of a polycarbonate external shield enclosing a custom diffusive housing made from expanded PTFE tubing. Two collection surfaces were investigated, gold …

Sources Of Gaseous Oxidized Mercury And Mercury Dry Deposition At Two Southeastern U.S. Sites, Peter S. Weiss-Penzias, Mae S. Gustin, Seth N. Lyman

USU Uintah Basin Faculty Publications

Wet deposition measurements have shown that relative to other parts of the US, the southeastern region has the highest mercury (Hg) inputs. The source of this Hg has been investigated by multiple researchers and is suggested to be derived from local, regional and global sources. Here we focus on trying to understand potential sources of Hg to this area during periods dominated by dry gaseous oxidized mercury (GOM) deposition. Dry deposition of GOM to a surrogate surface was measured in conjunction with speciated atmospheric Hg, and ancillary parameters from September 2007 through September 2008 at two sites located within 25 …

A Passive Sampler For Ambient Gaseous Oxidized Mercury Concentrations, Seth N. Lyman, Mae Sexauer Gustin, Eric M. Prestbo

USU Uintah Basin Faculty Publications

This paper reports on the development of a passive sampler for estimating gaseous oxidized mercury concentrations. Atmospheric gaseous oxidized mercury concentrations calculated from passive sampler data were correlated with those obtained using an automated analyzer (r2 = 0.71, p < 0.01, n = 110 for one-week deployments; r2 = 0.89, p < 0.01, n = 22 for two-week deployments). Sampler uptake was not significantly affected by changes in temperature, humidity, or ozone concentration, but it was slightly dependent on wind speed. As such, an equation for correcting data due to this factor was developed based on wind tunnel and field data. The detection limit for a two-week sampler deployment was ∼5 pg m−3. Field data collected in Nevada and the southeastern United States showed these samplers are useful for investigating spatial and temporal variability in gaseous oxidized mercury concentrations.

Atmospheric Mercury Concentrations And Speciation Measured From 2004 To 2007 In Reno, Nevada, Usa, Seth N. Lyman, Mae Sexauer Gustin

USU Uintah Basin Faculty Publications

Atmospheric elemental, reactive and particulate mercury (Hg) concentrations were measured north of downtown Reno, Nevada, USA from November 2004 to November 2007. Three-year mean and median concentrations for gaseous elemental Hg (Hg0) were 1.6 and 1.5 ng m−3 (respectively), similar to global mean Hg0 concentrations. The three-year mean reactive gaseous Hg (RGM) concentration (26 pg m−3) was higher than values reported for rural sites across the western United States. Well defined seasonal and daily patterns in Hg0 and RGM concentrations were observed, with the highest Hg0 concentrations measured in winter and early morning, and RGM concentrations being greatest in the …

Testing And Application Of Surrogate Surfaces For Understanding Potential Gaseous Oxidized Mercury Dry Deposition, Seth N. Lyman, Mae Sexauer Gustin, Eric M. Prestbo, Phillip I. Kilner, Eric Edgerton, Ben Hartsell

USU Uintah Basin Faculty Publications

Currently there is no standard method for measurement of atmospheric mercury dry deposition. While all operationally defined forms of atmospheric mercury (elemental, oxidized, and particulate) can be dry deposited, oxidized forms are of concern due to high deposition velocities, water solubility, and reactivity. This paper describes the development of a surrogate surface for characterizing potential dry deposition of gaseous oxidized mercury (GOM). Laboratory tests showed that the surface collected HgCl2, HgBr2, and HgO with equal efficiency, and deposition was not significantly influenced by temperature, humidity, or ozone concentrations. Deposition of mercury to surfaces in field deployments was correlated with GOM …

Determinants Of Atmospheric Mercury Concentrations In Reno, Nevada, U.S.A., Seth N. Lyman, Mae Sexauer Gustin

USU Uintah Basin Faculty Publications

Concentrations of gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM) and particulate-bound mercury (PBM) were measured along with ancillary variables 9 km east of downtown Reno, Nevada, U.S.A. from November 2006 through March 2009. Mean two-year (February 2007 through January 2009) GEM, GOM, and PBM concentrations were 2.0 ± 0.7 ng m− 3 (± standard deviation), 18 ± 22 pg m− 3, and 7 ± 7 pg m− 3, respectively. Data collected were compared with observations made at another location just north of the city at 169 m higher elevation. At both locations higher concentrations of GEM and PBM occurred …

Speciation Of Atmospheric Mercury At Two Sites In Northern Nevada, Usa, Seth N. Lyman, Mae Sexauer Gustin

USU Uintah Basin Faculty Publications

Gaseous elemental mercury (Hg0), reactive gaseous mercury (RGM), and mercury bound to particles (Hgp) were measured during seasonal 1- or 2-week data collection campaigns at two Mercury Deposition Network sites (NV02 and NV99) in northern Nevada, USA. The sites are rural but are located in an area of diverse natural and anthropogenic mercury sources that include undisturbed and mining mercury-disturbed enriched substrates, coal-fired power plants, ore processing facilities, and industrial facilities. Concentrations of Hg0 averaged over all campaigns were 3.0±1.7 ng m−3 at NV02 and 2.5±3.1 ng m−3 at NV99, higher than has been reported for other rural sites. Hg0 …

Seasonal And Diel Variation Of Atmospheric Mercury Concentrations In The Reno (Nevada, Usa) Airshed, Jelena Stamenkovic, Seth Lyman, Mae S. Gustin

USU Uintah Basin Faculty Publications

This paper describes total gaseous mercury (TGM) concentrations measured in Reno, Nevada from 2002 to 2005. The 3-year mean and median air Hg concentrations were 2.3 and 2.1 ng m−3, respectively. Mercury concentrations exhibited seasonality, with the highest concentrations in winter, and the lowest in summer and fall. A well-defined diel pattern in TGM concentration was observed, with maximum daily concentrations observed in the morning and minimum in the afternoon. A gradual increase of TGM concentration was observed in the evening and over night. The early morning increase in TGM was likely due to activation of local surface emission sources …

Estimation Of Dry Deposition Of Atmospheric Mercury In Nevada By Direct And Indirect Methods, Seth N. Lyman, Mae Sexauer Gustin, Eric M. Prestbo, Frank J. Marsik

USU Uintah Basin Faculty Publications

Atmospheric models and limited measurements indicate that dry deposition of atmospheric mercury is an important process by which mercury is input to ecosystems. To begin to fill the measurement data gap, multiple methods were used simultaneously during seasonal campaigns conducted in 2005 and 2006 to estimate dry deposition of atmospheric mercury at two Mercury Deposition Network (MDN) sites in rural Nevada and in Reno, Nevada. Gaseous elemental mercury (Hg0), reactive gaseous mercury (RGM), and particulate-bound mercury (Hgp) concentrations were measured using Tekran 2537A/1130/1135 systems. These speciated measurements were combined with on-site meteorological measurements to estimate depositional fluxes of RGM and …

Mercury Exchange Between The Atmosphere And Low Mercury Containing Substrates, Mae Sexauer Gustin, Mark Engle, Jody Ericksen, Seth N. Lyman, Jelena Stamenkovic, Mei Xin

USU Uintah Basin Faculty Publications

Mercury is emitted to the air from Hg-enriched and low Hg-containing (natural background) substrates. Emitted Hg can be geogenic, or can be derived from the re-emission of Hg that was previously deposited to the soil from the atmosphere. Atmospheric Hg can be derived from natural and/or anthropogenic sources and can be deposited by wet or dry processes. It is important to understand the relative magnitude of emission, deposition, and re-emission of Hg associated with terrestrial ecosystems with natural background soil Hg concentrations because these landscapes cover large terrestrial surface areas. This information is also important for developing biogeochemical mass balances, …