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Nrlmsis 2.0: A Whole-Atmosphere Empirical Model Of Temperature And Neutral Species Densities, J. T. Emmert, D. P. Drob, J. M. Picone, D. E. Siskind, M. Jones Jr., M. G. Mlynczak, Peter F. Bernath, X. Chu, E. Doornbos, B. Funke, L. P. Goncharenko, M. E. Hervig, M. J. Schwartz, P. E. Sheese, F. Vargas, B. P. Williams, T. Yuan 2020 Old Dominion University

Nrlmsis 2.0: A Whole-Atmosphere Empirical Model Of Temperature And Neutral Species Densities, J. T. Emmert, D. P. Drob, J. M. Picone, D. E. Siskind, M. Jones Jr., M. G. Mlynczak, Peter F. Bernath, X. Chu, E. Doornbos, B. Funke, L. P. Goncharenko, M. E. Hervig, M. J. Schwartz, P. E. Sheese, F. Vargas, B. P. Williams, T. Yuan

Chemistry & Biochemistry Faculty Publications

NRLMSIS® 2.0 is an empirical atmospheric model that extends from the ground to the exobase and describes the average observed behavior of temperature, eight species densities, and mass density via a parametric analytic formulation. The model inputs are location, day of year, time of day, solar activity, and geomagnetic activity. NRLMSIS 2.0 is a major, reformulated upgrade of the previous version, NRLMSISE-00. The model now couples thermospheric species densities to the entire column, via an effective mass profile that transitions each species from the fully mixed region below ~70 km altitude to the diffusively separated region above ~200 km. Other …


Developing A Uas-Deployable Methane Sensor Using Low-Cost Modular Open-Source Components, Gavin DeMali 2020 The University of Akron

Developing A Uas-Deployable Methane Sensor Using Low-Cost Modular Open-Source Components, Gavin Demali

Williams Honors College, Honors Research Projects

This project aimed to develop a methane sensor for deployment on an unmanned aerial system (UAS), or drone, platform. This design is centered around low cost, commercially available modular hardware components and open source software libraries. Once successfully developed, this system was deployed at the Bath Nature Preserve in Bath Township, Summit County Ohio in order to detect any potential on site fugitive methane emissions in the vicinity of the oil and gas infrastructure present. The deliverables of this project (i.e. the data collected at BNP) will be given to the land managers there to better inform future management and …


Optimization Of Regional Scale Numerical Weather Prediction & Air Quality Model For The Paso Del Norte Region, Suhail Mahmud 2020 University of Texas at El Paso

Optimization Of Regional Scale Numerical Weather Prediction & Air Quality Model For The Paso Del Norte Region, Suhail Mahmud

Open Access Theses & Dissertations

Improvement of the Accuracy and Forecast capability of the Numerical Weather Prediction (NWP) models and Air Quality Models (AQM) are critical issues in today's scientific study of Meteorology and Air Pollution. The models for these predictions are dependent on topography, climate, initial and boundary conditions, domain size, and computational efficiency. Different techniques such as Data Assimilation, Ensemble Methods, Increased Computing Capacity to achieve higher model resolution, and Improved Physics Schemes can be used to address this problem. In this study, the NWP models, the Weather and Research Forecast (WRF), and the HYSPLIT models, were enhanced for the Paso Del Norte …


Internet Of Things For Environmental Sustainability And Climate Change, Abdul Salam 2020 Purdue University

Internet Of Things For Environmental Sustainability And Climate Change, Abdul Salam

Faculty Publications

Our world is vulnerable to climate change risks such as glacier retreat, rising temperatures, more variable and intense weather events (e.g., floods, droughts, and frosts), deteriorating mountain ecosystems, soil degradation, and increasing water scarcity. However, there are big gaps in our understanding of changes in regional climate and how these changes will impact human and natural systems, making it difficult to anticipate, plan, and adapt to the coming changes. The IoT paradigm in this area can enhance our understanding of regional climate by using technology solutions, while providing the dynamic climate elements based on integrated environmental sensing and communications that …


Internet Of Things For Water Sustainability, Abdul Salam 2020 Purdue University

Internet Of Things For Water Sustainability, Abdul Salam

Faculty Publications

The water is a finite resource. The issue of sustainable withdrawal of freshwater is a vital concern being faced by the community. There is a strong connection between the energy, food, and water which is referred to as water-food-energy nexus. The agriculture industry and municipalities are struggling to meet the demand of water supply. This situation is particularly exacerbated in the developing countries. The projected increase in world population requires more fresh water resources. New technologies are being developed to reduce water usage in the field of agriculture (e.g., sensor guided autonomous irrigation management systems). Agricultural water withdrawal is also …


Assessing Agricultural Risk Management Using Historic Crop Insurance Loss Data Over The Ogallala Aquifer, Julian Reyes, Emile Elias, Erin M.K. Haacker, Amy Kremen, Lauren Parker, Caitlin Rottler 2020 U.S. Department of State, Washington, DC

Assessing Agricultural Risk Management Using Historic Crop Insurance Loss Data Over The Ogallala Aquifer, Julian Reyes, Emile Elias, Erin M.K. Haacker, Amy Kremen, Lauren Parker, Caitlin Rottler

Department of Earth and Atmospheric Sciences: Faculty Publications

Much of the agricultural production in the Ogallala Aquifer region relies on groundwater for irrigation. In addition to declining water levels, weather and climate-driven events affect crop yields and revenues. Crop insurance serves as a risk management tool to mitigate these perils. Here, we seek to understand what long-term crop insurance loss data can tell us about agricultural risk management in the Ogallala. We assess patterns and trends in crop insurance loss data from the U.S. Department of Agriculture Risk Management Agency. Indemnities, or insurance payments, totaled $22 billion from 1989–2017 for the 161 counties that overlie the Ogallala Aquifer. …


The Fluxnet2015 Dataset And The Oneflux Processing Pipeline For Eddy Covariance Data, Gilberto Pastorello, Timothy Arkebauer, Dave P. Billesbach, Anatoly Gitelson, Adam Liska, Andrew Suyker, Elizabeth Walter-Shea, More than 200 other 2020 Lawrence Berkeley National Laboratory, Berkeley, CA

The Fluxnet2015 Dataset And The Oneflux Processing Pipeline For Eddy Covariance Data, Gilberto Pastorello, Timothy Arkebauer, Dave P. Billesbach, Anatoly Gitelson, Adam Liska, Andrew Suyker, Elizabeth Walter-Shea, More Than 200 Other

Adam Liska Papers

The FLUXNET2015 dataset provides ecosystem-scale data on CO2, water, and energy exchange between the biosphere and the atmosphere, and other meteorological and biological measurements, from 212 sites around the globe (over 1500 site-years, up to and including year 2014). These sites, independently managed and operated, voluntarily contributed their data to create global datasets. Data were quality controlled and processed using uniform methods, to improve consistency and intercomparability across sites. The dataset is already being used in a number of applications, including ecophysiology studies, remote sensing studies, and development of ecosystem and Earth system models. FLUXNET2015 includes derived-data products, such as …


Deep Equatorial Pacific Ocean Oxygenation And Atmospheric Co2 Over The Last Ice Age, Franco Marcantonio, Ryan Hostak, Jennifer E. Hertzberg, Matthew W. Schmidt 2020 Old Dominion University

Deep Equatorial Pacific Ocean Oxygenation And Atmospheric Co2 Over The Last Ice Age, Franco Marcantonio, Ryan Hostak, Jennifer E. Hertzberg, Matthew W. Schmidt

OES Faculty Publications

Ventilation of carbon stored in the deep ocean is thought to play an important role in atmospheric CO2 increases associated with Pleistocene deglaciations. The presence of this respired carbon has been recorded by an array of paleoceanographic proxies from various locations across the global ocean. Here we present a new sediment core from the Eastern Equatorial Pacific (EEP) Ocean spanning the last 180,000 years and reconstruct high-resolution 230Th-derived fluxes of 232Th and excess barium, along with redox-sensitive uranium concentrations to examine past variations in dust delivery, export productivity, and bottom-water oxygenation, respectively. Our bottom-water oxygenation record is compared to …


Applications Of Drones In Atmospheric Chemistry, Travis J. Schuyler 2020 University of Kentucky

Applications Of Drones In Atmospheric Chemistry, Travis J. Schuyler

Theses and Dissertations--Chemistry

The emission of greenhouse gases (GHGs) has changed the composition of the atmosphere during the Anthropocene. A major technical and scientific challenge is quantifying the resulting fugitive trace gas fluxes under variable meteorological conditions. Accurately documenting the sources and magnitude of GHGs emission is an important undertaking for discriminating contributions of different processes to radiative forcing. Therefore, the adverse environmental and health effects of undetected gas leaks motivates new methods of detecting, characterizing, and quantifying plumes of fugitive trace gases. Currently, there is no mobile platform able to quantify trace gases at altitudes(UASs), or drones, can be deployed on-site in …


Atmospheric And Ionospheric Responses To Acoustic And Gravity Waves Driven By Earthquakes And Tsunamis, Pavel A. Inchin 2020 Embry-Riddle Aeronautical University

Atmospheric And Ionospheric Responses To Acoustic And Gravity Waves Driven By Earthquakes And Tsunamis, Pavel A. Inchin

Doctoral Dissertations and Master's Theses

Natural hazards (NHs) are causes for significant concern due to their potentially catastrophic impacts on society. The study of their effects on the upper atmosphere can provide significant insight into the coupled nature of geophysical processes, and drives important applications for radio communication and navigation, leading potentially to the development of NH early-warning systems. Although general concepts underlying their coupling mechanisms are well understood, recent computational capabilities, supported by high temporal and spatial density of observations, have reached the level where such processes can be modeled with unprecedented realism for detailed case studies. The studies provided in this thesis are …


An Analysis Of The Atmospheric Propagation Of Underground-Explosion-Generated Infrasonic Waves Based On The Equations Of Fluid Dynamics: Ground Recordings, Roberto Sabatini, Jonathan B. Snively, Michael P. Hickey, J. L. Garrison 2019 Embry-Riddle Aeronautical University

An Analysis Of The Atmospheric Propagation Of Underground-Explosion-Generated Infrasonic Waves Based On The Equations Of Fluid Dynamics: Ground Recordings, Roberto Sabatini, Jonathan B. Snively, Michael P. Hickey, J. L. Garrison

Publications

An investigation on the propagation of underground-explosion-generated infrasonic waves is carried out via numerical simulations of the equations of fluid dynamics. More specifically, the continuity, momentum, and energy conservation equations are solved along with the Herzfeld-Rice equations in order to take into account the effects of vibrational relaxation phenomena. The radiation of acoustic energy by the ground motion caused by underground explosions is initiated by enforcing the equality, at ground level, between the component of the air velocity normal to the Earth's surface and the normal velocity of the ground layer. The velocity of the ground layer is defined semi-empirically …


Land Cover Change Detection In The Urban Catchments Of Dar Es Salaam, Tanzania Using Remote Sensing And Gis Techniques, Philip Mzava, Joel Nobert, Patrick Valimba 2019 Department of Water Resources Engineering, Water Institute, P. O. Box 35059, Dar es Salaam, Tanzania.

Land Cover Change Detection In The Urban Catchments Of Dar Es Salaam, Tanzania Using Remote Sensing And Gis Techniques, Philip Mzava, Joel Nobert, Patrick Valimba

Tanzania Journal of Science

In this study, the Maximum Likelihood (ML) classification, Normalized Difference Vegetation Index (NDVI) and Artificial Neural Network (ANN) methods were applied to three (3) Landsat images collected over time (1979, 1998 and 2014), that contained historical land cover features for the urban catchments of Dar es Salaam. Five major land cover classes were identified, mapped, and the land cover changes investigated. The major land cover changes observed from post-classification comparisons of the classified images are: the forest land losing 17.09% of its area in the period 1979-1998 to other land covers, mainly turning to grassland, and from 1998 to 2014, …


The Role Of Multi-Charged Responses: Construction And Application Of A Tandem Differential Mobility Analyzer (Tdma), Christopher Ray Oxford 2019 Washington University in St. Louis

The Role Of Multi-Charged Responses: Construction And Application Of A Tandem Differential Mobility Analyzer (Tdma), Christopher Ray Oxford

McKelvey School of Engineering Graduate Student Theses & Dissertations

Atmospheric aerosols impact health outcomes, visibility, and the energy balance of the earth. The atmosphere contains a variety of compounds, and the volatility (phase change enthalpy and vapor pressure) of each compound determines its partitioning between the gas phase and the particle phase. The hygroscopicity (an aerosol’s affinity for water) of an atmospheric aerosol particle is determined by the many compounds present in the particle, and thus, the volatility impacts hygroscopicity. Changes in hygroscopicity alter the fraction of the aerosol deposited in the lungs and the fraction of the aerosol activated into cloud droplets. Thus, understanding the volatility and hygroscopicity …


Integrated Species–Phenon Trees: Visualizing Infraspecific Diversity Within Lineages, Abdullah Khan Zehady, Barry G. Fordham, James G. Ogg 2019 Purdue University

Integrated Species–Phenon Trees: Visualizing Infraspecific Diversity Within Lineages, Abdullah Khan Zehady, Barry G. Fordham, James G. Ogg

Purdue University Libraries Open Access Publishing Fund

The unprecedented detail with which contemporary molecular phylogenetics are visualizing infraspecific relationships within living species and species complexes cannot as yet be reliably extended into deep time. Yet paleontological systematics has routinely dealt in (mainly) morphotaxa envisaged in various ways to have been components of past species lineages. Bridging these perspectives can only enrich both. We present a visualization tool that digitally depicts infraspecific diversity within species through deep time. Our integrated species–phenon tree merges ancestor–descendant trees for fossil morphotaxa (phena) into reconstructed phylogenies of lineages (species) by expanding the latter into “species boxes” and placing the phenon trees inside. …


Steve And The Picket Fence: Evidence Of Feedback-Unstable Magnetosphere-Ionosphere Interaction, Evgeny Mishin, Anatoly Streltsov 2019 Air Force Research Laboratory

Steve And The Picket Fence: Evidence Of Feedback-Unstable Magnetosphere-Ionosphere Interaction, Evgeny Mishin, Anatoly Streltsov

Publications

This paper aims to extend the understanding of Strong Thermal Emission VelocityEnhancement (STEVE) and the Picket Fence related to strong subauroral ion drifts (SAID). Wenumerically demonstrated that precipitating energetic electrons are critical for the structuring of the PicketFence. It is created by feedback-unstable magnetosphere-ionosphere interactions driven by the SAIDelectric field when the Hall conductance created by energetic (≥1 keV) electrons exceeds the Pedersenconductance. We show that thermal excitation of the red-line emission in STEVE is inhibited by inelasticcollisions with molecular nitrogen. Suprathermal (≤500 eV) electrons coming from the turbulentplasmasphere appear to be the major source. We also show that the …


Determination Of Global Mean Eddy Diffusive Transport In The Mesosphere And Lower Thermosphere From Atomic Oxygen And Carbon Dioxide Climatologies, G. R. Swenson, C. C. J. H. Salinas, F. Vargas, Y. Zhu, M. Kaufmann, M. Jones Jr., A. Liu, et al. 2019 University of Illinois

Determination Of Global Mean Eddy Diffusive Transport In The Mesosphere And Lower Thermosphere From Atomic Oxygen And Carbon Dioxide Climatologies, G. R. Swenson, C. C. J. H. Salinas, F. Vargas, Y. Zhu, M. Kaufmann, M. Jones Jr., A. Liu, Et Al.

Publications

Quantifying the eddy diffusion coefficient profile in the mesosphere and lower thermosphere (MLT) is critical to the constituent density distributions in the upper mesosphere and thermosphere. Previous work by Swenson et al. (2018, https://doi.org/10.1016/j.jastp.2018.05.014) estimated the global mean eddy diffusion (kzz) values in the upper mesosphere using atomic oxygen (O), derived from Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) hydroxyl (OH). In this study, vertical eddy diffusive transport velocities of O were determined from continuity of mass in the mesopause region (80–97 km), primarily via the HOx chemistry. Global average constituent climatology from previously deduced SABER ozone (O3) …


A Numerical Investigation On The Variation Of Sodium Ion And Observed Thermospheric Sodium Layer At Cerro Pachón, Chile During Equinox, Xuguang Cai, Tao Yuan, J. Vincent Eccles, N. M. Pedatella, Xiaoqi Xi, Chao Ban, Alan Z. Liu 2019 Utah State University, Center for Atmospheric and Space Science

A Numerical Investigation On The Variation Of Sodium Ion And Observed Thermospheric Sodium Layer At Cerro Pachón, Chile During Equinox, Xuguang Cai, Tao Yuan, J. Vincent Eccles, N. M. Pedatella, Xiaoqi Xi, Chao Ban, Alan Z. Liu

Publications

The extension of the neutral sodium (Na) layer into the thermosphere (up to 170 km) has recently been observed at low and high latitudes using a Na lidar. However, the geophysical mechanisms and implications of its formation are currently unknown. In this study, we conduct an advanced two‐dimensional numerical simulation of the Na and Na+ variations in the E and F regions at low latitudes. The numerical simulations are used to investigate the contributions of the electromagnetic force, neutral wind, diffusion, and gravity. The simulations lead to three major findings. First, Na+ in the subtropical region of the geomagnetic equator …


Multilayer Observations And Modeling Of Thunderstorm-Generated Gravity Waves Over The Midwestern United States, C. J. Heale, J. B. Snively, A. N. Bhatt, L. Hoffmann, C. C. Stephan 2019 Embry-Riddle Aeronautical University

Multilayer Observations And Modeling Of Thunderstorm-Generated Gravity Waves Over The Midwestern United States, C. J. Heale, J. B. Snively, A. N. Bhatt, L. Hoffmann, C. C. Stephan

Publications

We present multilayer observations and numerical simulations of gravity waves (GWs) generated by a series of Mesoscale Convective Systems over the midwestern United States. Strong semiconcentric GWs were observed and modeled, which couple from their tropospheric sources to the thermosphere, displaying strong nonlinearity indicated by instability, breaking, and formation of turbulent vortices. GWs in the stratosphere display a large range of horizontal scales from 34–400 km; however, the smaller wavelength waves break rapidly in the mesosphere and lower thermosphere. Larger-scale (≥150 km) waves dominate in the thermosphere and display northwestward propagation at 200–300 km altitude, opposing the mean winds. Despite …


Umphlett Qci Dec 2019, Natalie A. Umphlett 2019 University of Nebraska-Lincoln

Umphlett Qci Dec 2019, Natalie A. Umphlett

High Plains Regional Climate Center: Staff Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Soil Moisture Conditions

Agriculture

Energy

Infrastructure

Temperature

Precipitation


Long-Term Aerosol Trends And Variability Over Central Saudi Arabia Using Optical Characteristics From Solar Village Aeronet Measurements, Mohammed Al Otaibi, Ashraf Farahat, Bassam Tawabini, M. Hafidz Omar, Emad Ramadan, Abdelgadir Abuelgasim, Ramesh Singh 2019 Environment, Health & Safety Support Section, Jubail Industrial City, Saudi Arabia

Long-Term Aerosol Trends And Variability Over Central Saudi Arabia Using Optical Characteristics From Solar Village Aeronet Measurements, Mohammed Al Otaibi, Ashraf Farahat, Bassam Tawabini, M. Hafidz Omar, Emad Ramadan, Abdelgadir Abuelgasim, Ramesh Singh

Mathematics, Physics, and Computer Science Faculty Articles and Research

Natural and anthropogenic aerosols over the Kingdom of Saudi Arabia (KSA) play a major role in affecting the regional radiation budget. The long-term variability of these aerosols’ physical and optical parameters, including aerosol optical depth (AOD) and Ångström exponent (α), were measured at a location near central KSA using the Solar Village (SV) AERONET (Aerosol Robotic Network) station during the period December 1999–January 2013. The AERONET measurements show an overall increase in AOD on an annual basis. This upward trend is mainly attributed to a prolonged increase in the monthly/seasonal mean AOD during March–June and during August– September. In contrast, …


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