Oceanography and Atmospheric Sciences and Meteorology Commons^™

2018 November - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

No abstract provided.

A Statistical Analysis Of Steve, Bea Gallardo‐Lacourt, Y. Nishimura, E. Donovan, G. W. Gillies, W. E. Archer, Omar A. Nava, E. L. Spanswick

Faculty Publications

There has been an exciting recent development in auroral research associated with the discovery of a new subauroral phenomenon called STEVE (Strong Thermal Emission Velocity Enhancement). Although STEVE has been documented by amateur night sky watchers for decades, it is as yet an unidentified upper atmosphere phenomenon. Observed first by amateur auroral photographers, STEVE appears as a narrow luminous structure across the night sky over thousands of kilometers in the east‐west direction. In this paper, we present the first statistical analysis of the properties of 28 STEVE events identified using Time History of Events and Macroscale Interactions during Substorms (THEMIS) …

Ice And Guano Deposits In El Malpais Lava Tubes: Potential Paleoclimate Archives For The Southwest United States, Dylan S. Parmenter

USF Tampa Graduate Theses and Dissertations

Three ice cores and one guano core were obtained from lava tubes in El Malpais National Monument, New Mexico, in the Southwest United States. A large hiatus in the Bat Cave guano record, resulting from mining activities in the early 1900's, left us with only ~50 years of data (from AD 1955-2006) to use in analysis. 13C values in guano (-18 to -11.6‰) primarily fall within the range of C4 plants, and likely indicate a tendency of Tadarida brasiliensis to feed on insects over grasslands to the North or South of the park. Variations in 13C values for this period …

Ground-Truthing Social Vulnerability Indices Of Alaska Fishing Communities, Anna Lavoie, Kim Sparks, Stephen Kasperski, Amber Himes-Cornell, Kristin Hoelting, Conor Maguire

All Faculty Scholarship for the College of the Sciences

Community vulnerability is increasingly evaluated through quantitative social indices, typically developed using secondary data sources rather than primary data collection. It is necessary to understand the validity of these indices if they will be used to inform policy and decision making. This paper presents a ground-truthing effort to validate quantitative indices that characterize the well-being of Alaska fishing communities. We utilized ethnographic data collected from 13 representative communities and a capital assets framework to ground-truth the indices, in which qualitative ranks of vulnerability were compared against quantitative indices. The majority (73.8%) of ranks were in complete or moderate agreement and …

On The Existence Of Ionospheric Feedback Instability In The Earth’S Magnetosphere-Ionosphere System, Anatoly V. Streltsov, Evgeny V. Mishin

Publications

The ionospheric feedback instability (IFI) has been considered one of the main generation mechanisms for large-amplitude ultralow frequency waves and small-scale field-aligned currents in the auroral and subauroral regions for more than 40 years. Sydorenko and Rankin (2017, https://doi.org/10.1002/2017GL073415) have recently challenged the very existence of the IFI for any realistic geophysical conditions in the Earth's ionosphere-magnetosphere system. Because this conclusion contradicts numerous theoretical, numerical, and experimental works successfully used IFI to explain and predict results from observations for more than four decades, it deserves special attention. We show that this conclusion is mainly based on the specific ionospheric …

On The Asymmetry Between Upward And Downward Field-Aligned Currents Interacting With The Ionosphere, A. V. Streltsov

Publications

The paper presents results from the numerical study of the magnetosphere-ionosphere interactions driven by the large-scale electric field in the magnetically conjugate, high-latitude regions of northern and southern hemispheres. Simulations of the two-fluid MHD model demonstrate that these interactions can lead to a generation of a system of small-scale, intense field-aligned currents with a significant difference in size and amplitude between the upward and downward currents. In particular, in both hemispheres, the downward currents (where the electrons are flowing from the ionosphere) become more narrow and intense than the adjacent upward currents. At high latitudes, the field-aligned currents are closely …

Scale Dependence Of Cloud Microphysical Response To Turbulent Entrainment And Mixing, Bipin Kumar, Paul Gotzfried, Neethl Suresh, Jörg Schumacher, Raymond Shaw

Michigan Tech Publications, Part 1

The dynamics and lifetime of atmospheric clouds are tightly coupled to entrainment and turbulent mixing. This paper presents direct numerical simulations of turbulent mixing followed by droplet evaporation at the cloud‐clear air interface in a meter‐sized volume, with an ensemble of up to almost half a billion individual cloud water droplets. The dependence of the mixing process on domain size reveals that inhomogeneous mixing becomes increasingly important as the domain size is increased. The shape of the droplet size distribution varies strongly with spatial scale, with the appearance of a pronounced negative exponential tail. The increase of relative dispersion during …

Mulholland Leading Volunteer Effort To "Measure The Muck" In Chesapeake Bay Oct. 27, News @ Odu

News Items

No abstract provided.

Eddy Flux Measurements Of Sulfur Dioxide Deposition To The Sea Surface, Jack G. Porter, Warren J. De Bruyn, Eric S. Saltzman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Deposition to the sea surface is a major atmospheric loss pathway for many important trace gases, such as sulfur dioxide (SO2). The air–sea transfer of SO2 is controlled entirely on the atmospheric side of the air–sea interface due to high effective solubility and other physical– chemical properties. There have been few direct field measurements of such fluxes due to the challenges associated with making fast-response measurements of highly soluble trace gases at very low ambient levels. In this study, we report direct eddy covariance air–sea flux measurements of SO2, sensible heat, water vapor, and momentum. The measurements were made over …

Local Warming In Low Latitude Locations: A Time Series Analysis, Ryan Pittman

Rose-Hulman Undergraduate Mathematics Journal

Global warming is a well-known and well-studied phenomenon pertaining to a gradual increase of average global temperatures over time. Many global warming mathematical models make certain assumptions regarding the factors that impact global temperature. These assumptions include effects from increased global carbon dioxide levels in the atmosphere and the melting ice sheets, among others. This paper draws conclusions about temperature changes without the assumptions needed for the global warming mathematical models. Instead of using computer models to project temperatures on a global scale, 33 low-latitude locations in the southern United States were individually studied to see if each one has …

Turbulence Induced Cloud Voids: Observation And Interpretation, Katarzyna Karpinska, Jonathan F. E. Bodenschatz, Szymon P. Malinowski, Jakub L. Nowak, Steffen Risius, Tina Schmeissner, Raymond Shaw, Holger Siebert, Hengdong Xi, Haitao Xu, Eberhard Bodenschatz

Department of Physics Publications

The phenomenon of cloud voids, i.e., elongated volumes inside a cloud that are devoid of droplets, was observed with laser sheet photography in clouds at a mountain-top station. Two experimental cases, similar in turbulence conditions yet with diverse droplet size distributions and cloud void prevalence, are reported. A theoretical explanation is proposed based on the study of heavy inertial sedimenting particles inside a Burgers vortex. A general conclusion regarding void appearance is drawn from theoretical analysis. Numerical simulations of polydisperse droplet motion with realistic vortex parameters and Mie scattering visual effects accounted for can explain the presence of voids with …

Tidal-, Wind-, And Buoyancy-Driven Dynamics In The Barataria Estuary And Its Impact On Estuarine-Shelf Exchange Processes, Linlin Cui

LSU Doctoral Dissertations

A three-dimensional, high-resolution, Finite-Volume Coastal Ocean Model (FVCOM) was used to study the dynamics of Barataria Estuary located in the Southeastern Louisiana. Three numerical experiments with different discharge scenarios, including the actual discharge (average ~ 160 m³ s^-1) from the Davis Pond Diversion (DPD) over three months from April to June 2010, no discharge (NO), and the proposed Mid-Barataria Diversion (MBD) with a constant discharge of 850 m³ s^-1, were conducted to investigate the impacts of river diversions on salinity gradients and residence times in the estuary. The three-month average salinity indicated that surface …

The 'New Normal' Of Flooding In Portsmouth, Virginia: Perspectives, Experiences, And Adaptive Responses Of Residents And Business Owners In Low To Moderate-Income Communities, Donta Council, Michelle Covi, Wie Yusuf, Joshua Behr, Makayla Brown, Old Dominion University Resilience Collaborative, Virginia Sea Grant

Presentations, Lectures, Posters, Reports

[First three paragraphs from the Summary]

This project is a part of a broader initiative - the Resilience Adaptation Feasibility Tool (RAFT) - that addresses the daunting challenges coastal communities are facing related to sea level rise and climate change (more information about RAFT is available here: https://ien.virginia.edu/raft).

This aim of this project was to investigate how residents and business owners in low-to-moderate income communities in Portsmouth, Virginia cope with flooding, and to assess implications for how the local government can better engage with residents to better meet their information needs so they can be more resilient to flooding. The …

Estimation Of Atmospheric Turbulence Using Differential Motion Of Extended Features In Time-Lapse Imagery, Santasri R. Bose-Pillai, Jack E. Mccrae, Christopher A. Rice, Ryan A. Wood, Conner E. Murphy, Steven T. Fiorino

Faculty Publications

We address the design, development, and testing of a pointer/tracker as a probe beam for the purpose of making high-speed, aero-optical measurements of the flow over a scaled beam director turret. The tracker uses retro-reflection of the probe beam off of a Reflexite annulus surrounding the turret. The constraints of the design required a near-total-commercial off the shelf system that could be quickly installed and removed in a rented aircraft. Baseline measurements of environmental vibrations are used to predict pointing performance; mitigation of line-of-sight jitter on the probe beam is achieved through passive isolation and the design of relay optics. …

Interpreting Aviation Weather Products: Follow-Up Study With Aopa Members, Beth Blickensderfer, Thomas A. Guinn, Thomas Bob, Jayde King, Yolanda Ortiz, Nick Defilippis, Quirijn Berendschot, Jacqueline Mcsorley

General Aviation Weather Display Interpretation

Purpose

• Use the questions we developed in Phase I
• Include pilots that are more representative of GA (age, flight hours/experience); Collaborate with AOPA
• Examine: Knowledge about aviation weather products; Differences between levels of flight certificate and/or ratings

Assessing Ga Pilots' Preflight Weather Planning Mental Models, Yolanda Ortiz, Beth Blickensderfer, Thomas A. Guinn

General Aviation Weather Display Interpretation

Purpose, To assess GA Pilots' ability to:

• Obtain the Appropriate Weather Information
• Interpret the Data
• Apply the Information to a Given Flight Route

Aviation Weather Education: Challenges Using Current Faa Guidance, Thomas A. Guinn, Robert Thomas

Aviation Weather Training Research

Observed Challenges

• Incorrect product information
• Guidance not keeping pace with new products
• Multiple formats of same product
• Potentially unnecessary information
• Missing product information
• Limited focus on interpretation

Challenges For Flight Instructors Teaching Weather Information, Robert Thomas, Thomas A. Guinn

Aviation Weather Training Research

• Flight Instructors face a challenge when teaching/learning weather information
• Multiple overlapping resources for aviation weather
• AC takes longer timeframe to update –problem for quick updates of information

Quantitative Validation Of Simulated Sea Ice Displacements, Bryan R. Mccormick

Mathematics & Statistics ETDs

Accurate simulations of Arctic sea ice are important for forecasting as well as for understanding the global climate. However, quantitative measures for simulation displacements are underutilized. We present five such measures proposed as being useful in the validation of simulated sea ice displacements. Using drifting buoy and satellite measurements of sea ice motion as observation, we apply the metrics in a comparison of observed displacements and predicted displacements from the Arctic sea ice simulation MPM\_ice. We find the metric scores are useful for comparing simulations and observations. The metrics also brought to light problems in the simulation MPM_ice, demonstrating their …

October Science Pub: Using Technology To Map The Effects Of Sea Level Rise, Amy Matzke-Fawcett

News Items

No abstract provided.