Oceanography and Atmospheric Sciences and Meteorology Commons^™

2024 May - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

No abstract provided.

Catchment-Scale Thawing And Greening Decreases Long-Term Nitrogen Export In Ne Greenland, Shannon L. Speir, Jennifer L. Tank, Ada Pastor, Marc F. Muller, Mikhail Mastepanov, Tenna Riis

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Climate change is expected to alter nitrogen (N) export from Arctic rivers, with potential implications for fragile coastal ecosystems and fisheries. Yet, the directionality of change is poorly understood, as increased mobilization of N in a 'thawing' Arctic is countered by higher rates of vegetative uptake in a 'greening' Arctic, particularly in the understudied region of Greenland. We use an unprecedented dataset of long-term (n = 18 years) river chemistry, streamflow, and catchment-scale changes in snow and vegetation to document changing riverine N loss in Greenland. We documented decreasing inorganic and organic N loads, linked to decreasing snow stores, …

Lake Mead: A Living Museum, Marley Salveter

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lake Mead, the largest man-made water project in the nation and a prolific source of electricity, irrigation, and recreation for much of the western population, is currently experiencing a drastic transformation. Amid the ongoing water crisis parching the west, the once overflowing reservoir is consistently shrinking, descending into depths historically uncharted.

While serving as a bleak demonstration of climate change’s effects, the body of water is simultaneously assuming an alternative role that may be less apparent to the public. As water levels decline, Lake Mead is actively metamorphosing into a “Living Museum”, by gradually unveiling previously submerged artifacts. As a …

Deterministic Global 3d Fractal Cloud Model For Synthetic Scene Generation, Aaron M. Schinder, Shannon R. Young, Bryan J. Steward, Michael L. Dexter, Andrew Kondrath, Stephen Hinton, Ricardo Davila

Faculty Publications

This paper describes the creation of a fast, deterministic, 3D fractal cloud renderer for the AFIT Sensor and Scene Emulation Tool (ASSET). The renderer generates 3D clouds by ray marching through a volume and sampling the level-set of a fractal function. The fractal function is distorted by a displacement map, which is generated using horizontal wind data from a Global Forecast System (GFS) weather file. The vertical windspeed and relative humidity are used to mask the creation of clouds to match realistic large-scale weather patterns over the Earth. Small-scale detail is provided by the fractal functions which are tuned to …

El Nino Prediction At 1- And 3- Year Lead Times Driven By The Western North Pacific Precursor And Their Impacts, Krishna Borhara

All Graduate Theses and Dissertations, Fall 2023 to Present

The El Niño–Southern Oscillation (ENSO) is a climate variability characterized by fluctuations in the atmospheric and upper ocean conditions of the tropical Pacific Ocean that result in either warmer- or colder-than-average sea surface temperatures (SST) in the tropical eastern Pacific. These changes cause variations in weather and climate in distant locations through large-scale atmospheric circulation patterns. These variations often manifest in form of adverse effects or extremes such as heat waves, droughts, or floods, making efforts towards improving ENSO prediction critical in mitigating its impact on various sectors. This dissertation focuses on how interactions between the atmosphere and ocean in …

Angular Distribution Of Bremsstrahlung Spectral Temperature Measured In A Full Dimension Of Ecr Ion Source Using Nai(Ti) Detector, Mwingereza J. Kumwenda

Tanzania Journal of Science

Measurement of angular distribution (AD) of the bremsstrahlung spectral temperature from a full dimension of the Electron Cyclotron Resonance Ion Source (ECRIS) along the beam axis is challenging. To overcome some challenges, this paper presents the AD of the bremsstrahlung spectral temperature measured in a full dimension of the ECRIS along the beam axis using data obtained from the Busan Center of Korea Basic Science Institute (KBSI). The bremsstrahlung spectral temperature from 28-GHz ECR Ion source at the KBSI was measured in six, three, and nine azimuthal angles at the injection, centre, and extraction sides of the ECRIS using three …

Investigating Turbulence Distribution In The Lower Atmosphere Using Time-Lapse Imagery From A Camera Bank, Benjamin C. Wilson, Santasri R. Bose-Pillai, Jack E. Mccrae, Steven T. Fiorino, Robert P. Freeman, Laura R. Slabaugh

Faculty Publications

The atmosphere’s surface layer (first 50–100 m above the ground) is extremely dynamic and is influenced by surface radiative properties, roughness, and atmospheric stability. Understanding the distribution of turbulence in the surface layer is critical to many applications, such as directed energy and free space optical communications. Several measurement campaigns in the past have relied on weather balloons or sonic detection and ranging (SODAR) to measure turbulence up to the atmospheric boundary layer. However, these campaigns had limited measurements near the surface. We have developed a time-lapse imaging technique to profile atmospheric turbulence from turbulence-induced differential motion or tilts between …

Net Fluxes Of Broadband Shortwave And Photosynthetically Active Radiation Complement Ndvi And Near Infrared Reflectance Of Vegetation To Explain Gross Photosynthesis Variability Across Ecosystems And Climate, Kanishka Mallick, Joseph Verfaillie, Tianxin Wang, Ariane Arias Ortiz, Daphne Szutu, Koong Yi, Yanghui Kang, Robert Shortt, Tian Hu, Mauro Sulis, Zoltan Szantoi, Gilles Boulet, Joshua B. Fisher, Dennis Baldocchi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

A significant challenge in global change research is understanding how vegetation interacts with the environment to influence ecosystem gross primary productivity (GPP) through carbon assimilation. One emerging objective is to consistently predict GPP fluctuations worldwide by establishing a robust scaling relationship between GPP measured at flux towers and satellite spectral reflectance data. However, a major hurdle in achieving this goal is the discrepancy in spatial resolution between early satellite measurements and eddy flux measurements. By using a large set of growing season data covering 100 site-years in North and Central America, we explored the potential of transforming incident and reflected …

2024 April 25 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Seagrass Conservation And Restoration To Mitigate Ocean Acidification And Climate Change, Tori Benson, Emi Wagner, Jaeger Reed

Celebrating Scholarship and Creativity Day (2018-)

For millennia, various seagrass species have been sequestering and anchoring aquatic carbon into oceanic sediment. The crucial role of seagrasses involves helping mitigate climate change, which emphasizes the urgent need to conserve, sustain, and manage them as part of global climate action efforts. Restoration and conservation studies have shown significant reversal of potential damaging effects, however human activity continues to set back efforts faster than they can proceed. Multiple studies have concluded that there has been a decline in seagrass meadows in previously dense areas; and due to this, surrounding pH levels have declined and rising atmospheric carbon poses a …

A Climatology Of North American Monsoon Precipitation Over Arizona From Mrms Data, Greta Graeler, Mark Sinclair, Curtis N. James

Publications

The North American Monsoon (NAM) is a seasonal shift in pressure and wind which accounts for over half of the southwest’s annual precipitation. North-central Arizona has variable terrain which influences the location and intensity of convective storms. Severe weather such as strong winds, lightning, and hail can cause loss of life, property, and fires. High spatial and temporal resolution data along with reanalysis data is used to identify convective cells and their motion for the 2015 to 2022 NAM seasons. The heaviest precipitation in north-central Arizona is found over the Bradshaw Mountains and is most active in July and August. …

Investigation Of Surface Chemistry From Electron Irradiation Of Synthetic Schreibersite, Tyler Davis

Master's Theses

While phosphorus is one of the key elements for life on Earth, it has relatively low abundance in extraterrestrial environments, making it a target for astronomers and astrobiologists interested in the possibility of life beyond our planet. Schreibersite (Fe,Ni)₃P is one of the first P-containing minerals to condense during planetary cooling and one of the primary P-containing minerals in iron and stony-iron meteorites. Therefore, it is a likely P-bearing mineral in cometary cores and dust grains within the interstellar medium and circumstellar envelopes. Experiments in this project were performed with the aim of observing the formation of small …

Benthic Community Response To The Impacts Of Proposed Sediment Diversions In Louisiana Estuaries, Jillian C. Tupitza

LSU Doctoral Dissertations

Sediment diversions designed to mitigate land loss in coastal Louisiana will likely cause ecosystem-wide shifts. The first diversion, planned for Barataria Bay, will divert fresh water and sediment from the Mississippi River into the surrounding wetlands to help them keep pace with high rates of relative sea-level rise (RSLR). Estuarine benthic communities were used in this study as tools to characterize ecological patterns in the context of anticipated salinity changes. I reviewed relevant literature, conducted a two-year survey of Barataria Bay benthos, executed a reciprocal transplant experiment to describe changes that might occur in both community composition and trophic dynamics, …

Kinematic And Dynamic Structure Of The 18 May 2020 Squall Line Over South Korea, Wishnu Agum Swastiko, Chia-Lun Tsai, Seung Hee Kim, Gyuwon Lee

Institute for ECHO Articles and Research

The diagonal squall line that passed through the Korean Peninsula on the 18 May 2020 was examined using wind data retrieved from multiple Doppler radar synthesis focusing on its kinematic and dynamic aspects. The low-level jet, along with warm and moist air in the lower level, served as the primary source of moisture supply during the initiation and formation process. The presence of a cold pool accompanying the squall line played a role in retaining moisture at the surface. As the squall line approached the Korean Peninsula, the convective bands in the northern segment (NS) and southern segment (SS) of …

2024 April 18 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Volumetric Reconstruction Of Ionospheric Electric Currents From Tri-Static Incoherent Scatter Radar Measurements, Jone Peter Reistad, Spencer Mark Hatch, Karl M. Laundal, Kjellmar Oksavik, Matthew David Zettergren, Heikki Vanhamaki, Ilkka I. Virtanen

Publications

We present a new technique for the upcoming tri-static incoherent scatter radar system EISCAT 3D (E3D) to perform a volumetric reconstruction of the 3D ionospheric electric current density vector field, focusing on the feasibility of the E3D system. The input to our volumetric reconstruction technique are estimates of the 3D current density perpendicular to the main magnetic field, $\mathbf{j} \perp$, and its co-variance, to be obtained from E3D observations based on two main assumptions: 1) Ions fully magnetised above the $E$ region, set to 200 km here. 2) Electrons fully magnetised above the base of our domain, set to 90 …

2024 April 11 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Chemtrails: Deadly Skies Or Dangerous Misinformation?, Abigail Foust

Undergraduate Research Symposium

A common sight on a clear day is a thin strip of white across the otherwise blue sky: A contrail. Most people do not think anything of these contrails, and assume they have little to no impact on the world at large. Suppose for a moment, however, that they are not as harmless as some believe. Suppose these cloud trails are actually composed of dangerous chemicals, and are being used by sinister forces in a conspiracy to kill off the weak, mind-control the population, or simply dull our minds in preparation for a government takeover. As far-fetched as this may …

The 2022 Hunga Tonga Volcanic Eruption's Impact On Radio Communications, Spencer Brothers

Student Research Symposium

On January 15^th 2022, the Hunga Tonga volcanic eruption, Figure 1, ejected unprecedented amounts of water into the stratosphere. The resulting plume may present temporary opportunities for long distance radio communication.

Climatology Of Tornadoes In Kansas, John P. Wasinger, Todd Moore

SACAD: Scholarly Activities

Recent studies report changes to the climatology of tornadoes in the United States (US). Changes with the most supporting evidence include an increase in the intra- and inter-annual variability, increased concentration of tornadoes in bigger outbreaks, and a geographic shift of the densest tornado activity away from Tornado Alley in the Great Plains and toward the Great Lakes and Southeast regions of the US. Broad, national-level changes are valuable, but they can mask changes occurring at the state and sub-state levels where mitigation efforts are most effective. Kansas is of interest due to its reputation as a hotbed of tornado …