Surviving Under The Reign Of El Niño Southern Oscillation: An Analysis Of The Effects Of Extreme El Niño Events On The Oceanographic And Biological Environment Of The Galápagos Islands,
2020
SIT Study Abroad
Surviving Under The Reign Of El Niño Southern Oscillation: An Analysis Of The Effects Of Extreme El Niño Events On The Oceanographic And Biological Environment Of The Galápagos Islands, Ava Mcilvaine
Independent Study Project (ISP) Collection
El Niño Southern Oscillation (ENSO) is commonly known as the atmospheric and oceanographic powerhouse of the Southern Pacific Ocean. From phytoplankton to apex predators, ENSO controls the stability of species’ populations within this biodiverse ocean environment. El Niño’s 9-15 month alteration of the heat storage in the tropical Pacific drastically shifts the temperature, nutrient, and circulation gradient its marine life is accustomed to. A single degree change in the ocean’s surface layer temperature can have large consequences for marine species, and El Niño is commonly associated with Sea Surface Temperature Anomalies (SSTAs) between 2°- 6° Celsius. The potential danger El …
Trend Analyses Of The Abundances Of Atmospheric Molecules,
2020
Old Dominion University
Trend Analyses Of The Abundances Of Atmospheric Molecules, Anton Fernando
Physics Theses & Dissertations
A new line list for the A3Π - X3Σ- electronic transition of NH has been prepared using line positions from the literature and calculated line intensities. High level ab initio calculations were performed with the MOLPRO program to obtain the A - X transition dipole moment function. Potential energy curves and line strengths were calculated with Le Roy's RKR1 and LEVEL programs. Line intensities and Einstein A values were calculated with Western's PGOPHER program after converting the Hund's case (b) output of LEVEL to Hund's case (a) input needed for PGOPHER. The Herman- Wallis effect is …
Validation Technique For Modeled Bottomside Ionospheres Via Ray Tracing,
2020
Air Force Institute of Technology
Validation Technique For Modeled Bottomside Ionospheres Via Ray Tracing, Kevin S. Burg
Theses and Dissertations
A new method for validating ionosphere models using High Frequency (HF) angle of arrival (AoA) data is presented. AoA measurements from a field campaign held at White Sands Missile Range, New Mexico, USA in January 2014 provide the actual elevation angle, azimuth and group delay results from 10 transmitter-receiver circuits. Simulated AoAs are calculated by ray tracing through the electron density profiles predicted from the ionosphere models hosted by NASA's Community Coordinated Modeling Center: IRI-2016, USU-GAIM, GITM, CTIPe, TIE-GCM, and SAMI3. Through the implementation of metrics including Mean Absolute Error, Prediction Efficiency, Correlation Coefficient, and others, we are able to …
Changes In Atmospheric, Meteorological, And Ocean Parameters Associated With The 12 January 2020 Taal Volcanic Eruption,
2020
China Earthquake Administration
Changes In Atmospheric, Meteorological, And Ocean Parameters Associated With The 12 January 2020 Taal Volcanic Eruption, Feng Jing, Akshansa Chauhan, Ramesh P. Singh, Prasanjit Dash
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
The Taal volcano erupted on 12 January 2020, the first time since 1977. About 35 mild earthquakes (magnitude greater than 4.0) were observed on 12 January 2020 induced from the eruption. In the present paper, we analyzed optical properties of volcanic aerosols, volcanic gas emission, ocean parameters using multi-satellite sensors, namely, MODIS (Moderate Resolution Imaging Spectroradiometer), AIRS (Atmospheric Infrared Sounder), OMI (Ozone Monitoring Instrument), TROPOMI (TROPOspheric Monitoring Instrument) and ground observations, namely, Argo, and AERONET (AErosol RObotic NETwork) data. Our detailed analysis shows pronounced changes in all the parameters, which mainly occurred in the western and south-western regions because the …
Methanethiol, Dimethyl Sulfide And Acetone Over Biologically Productive Waters In The Southwest Pacific Ocean,
2020
ommonwealth Scientific and Industrial Research Organisation (CSIRO), Australia
Methanethiol, Dimethyl Sulfide And Acetone Over Biologically Productive Waters In The Southwest Pacific Ocean, Sarah J. Lawson, Cliff S. Law, Mike J. Harvey, Thomas G. Bell, Carolyn F. Walker, Warren J. De Bruyn, Eric S. Saltzman
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Atmospheric methanethiol (MeSHa), dimethyl sulfide (DMSa) and acetone (acetonea) were measured over biologically productive frontal waters in the remote southwest Pacific Ocean in summertime 2012 during the Surface Ocean Aerosol Production (SOAP) voyage. MeSHa mixing ratios varied from below the detection limit (< 10 ppt) up to 65 ppt and were 3 %–36 % of parallel DMSa mixing ratios. MeSHa and DMSa were correlated over the voyage (R2=0.3, slope = 0.07) with a stronger correlation over a coccolithophore-dominated phytoplankton bloom (R2=0.5, slope 0.13). The diurnal cycle for MeSHa shows similar behaviour to DMSa with mixing ratios …
What Is The Most Threatening Disaster To The Continental United States?,
2020
University of Nebraska at Omaha
What Is The Most Threatening Disaster To The Continental United States?, Aaron Spomer, Elijah Kaufman, Julisa Prieto-Garcia, Brooke Aschwanden
UNO Student Research and Creative Activity Fair
Our goal for our project is to fully understand which natural disaster is the most destructive to the United States. We have chosen to compare hurricanes, floods, tornadoes, wildfires, earthquakes, and nor’easters. We have researched the cost of the total damage and repair, how the warning systems have improved over time, the death tolls from each, and also the frequency at which each one occurs. Each group member will research a different disaster impact, and the data will create a comprehensive view of the level of devastation each disaster has. We collected data all the way from the early 1900s …
Next-Generation Air Force Weather Metrics Via Bayes Cost Analysis,
2020
Air Force Institute of Technology
Next-Generation Air Force Weather Metrics Via Bayes Cost Analysis, Brandon M. Bailey
Theses and Dissertations
This research proposes a new methodology for U.S. Air Force weather forecast metrics. Military weather forecasters are essentially statistical classifiers. They categorize future conditions into an operationally relevant category based on current data, much like an Artificial Neural Net or Logistic Regression model. There is extensive literature on statistically-based metrics for these types of classifiers. Additionally, in the U.S. Air Force, forecast errors (errors in classification) have quantifiable operational costs and benefits associated with incorrect or correct classification decisions. There is a methodology in the literature, Bayes Cost, which provides a structure for creating statistically rigorous metrics for classification decisions …
Detection Of Reconnection Signatures In Solar Flares,
2020
Air Force Institute of Technology
Detection Of Reconnection Signatures In Solar Flares, Taylor R. Whitney
Theses and Dissertations
Solar flare forecasting is limited by the current understanding of mechanisms that govern magnetic reconnection, the main physical phenomenon associated with these events. As a result, forecasting relies mainly on climatological correlations to historical events rather than the underlying physics principles. Solar physics models place the neutral point of the reconnection event in the solar corona. Correspondingly, studies of photospheric magnetic fields indicate changes during solar flares -- particularly in relation to the field helicity -- on the solar surface as a result of the associated magnetic reconnection. This study utilizes data from the Solar Dynamics Observatory (SDO) Helioseismic and …
Determining Bulk Aerosol Absorption From Off Axis Backscattering Using Rayleigh Beacon Laser Pulses,
2020
Air Force Institute of Technology
Determining Bulk Aerosol Absorption From Off Axis Backscattering Using Rayleigh Beacon Laser Pulses, Julie C. Grossnickle
Theses and Dissertations
Aerosol absorption and scattering can play a key role in degrading high energy laser performance in the form of thermal blooming and beam attenuation. Aerosol absorption properties are not completely understood, and thus affect how we are able to quantify expected high energy laser weapon performance. The Air Force Institute of Technology Center for Directed Energy (AFIT CDE) developed both Laser Environmental Effects Definition and Reference (LEEDR) and the High Energy Laser End-to-End Operational Simulation (HELEEOS) code to characterize atmospheric radiative transfer effects and evaluate expected directed energy weapon system performance. These packages enable modeling of total irradiance at given …
Modulation Of Lightning Occurrence By The Solar Wind,
2020
Air Force Institute of Technology
Modulation Of Lightning Occurrence By The Solar Wind, Adam L. Baxter
Theses and Dissertations
Lightning affects military and civilian operations. Characterization of the distribution of global lightning strikes of two detection networks based on solar wind events is analyzed. the median analysis by latitude gave different results for the two network datasets. The KLD pulled out some common features such as the seasonal dependence and a general increase in lightning at the equator. Comparisons between different datasets must be handled carefully. the KLD method may be a way to capture common features, or assess how similar the datasets are. A detailed analysis of the differences between the tow networks detection algorithms and investigating other …
A Method For Routine Pm2.5 Obsercation And Incorporation Into Numerical Weather Prediction,
2020
Air Force Institute of Technology
A Method For Routine Pm2.5 Obsercation And Incorporation Into Numerical Weather Prediction, Daniel B. Jagoda
Theses and Dissertations
Operational numerical weather prediction (NWP) simulates aerosol abundance using climatic emission inventories due to a lack of available real-time observation. An advocation to monitor aerosol number concentration with a standardized global sensor network is defended. A comparison between observations from the existing network “PurpleAir” and condensation particle counters (CPC) reveals the necessity of regulated instrumentation when measuring aerosol number concentration. NWP initialization by the Goddard Chemistry Aerosol Radiation and Transport (GOCART) module is capable of augmentation by hourly aerosol observation. The disparity between observed in-situ particulate matter smaller than 2.5-μm in diameter (PM2.5) and Weather Research and Forecasting …
Characterizing Regime-Based Flow Uncertainty,
2020
Air Force Institute of Technology
Characterizing Regime-Based Flow Uncertainty, John L. Fioretti
Theses and Dissertations
The goal of this work is to develop a regime-based quantification of horizontal wind field uncertainty utilizing a global ensemble numerical weather prediction model. In this case, the Global Ensemble Forecast System Reforecast (GEFSR) data is utilized. The machine learning algorithm that is employed is the mini-batch K-means clustering algorithm. 850 hPa Horizontal flow fields are clustered and the forecast uncertainty in these flow fields is calculated for different forecast times for regions across the globe. This provides end-users quantified flow-based forecast uncertainty.
Localized Effects Of Hurricane Michael (2018) On Total Electron Content,
2020
Air Force Institute of Technology
Localized Effects Of Hurricane Michael (2018) On Total Electron Content, Joanna E.S. Williams
Theses and Dissertations
Understanding the connection between terrestrial and space environments is an emerging field of study that can significantly improve operational weather forecasting. In particular, it is well known that tropical cyclones (TCs) and thunderstorms can initiate gravity waves that generate fluctuations in the total electron content (TEC) of the ionosphere. These perturbations can deteriorate and delay the transmission of high-frequency (HF) communications, such as emergency services, amateur radio, and aviation. This study investigates changes in TEC according to the number of lightning ashes and the rainfall rates associated with Hurricane Michael (2018). A composite analysis will be performed using the GOES …
Simulation Of Sporadic-E Parameters Using Phase Screen Method,
2020
Air Force Institute of Technology
Simulation Of Sporadic-E Parameters Using Phase Screen Method, Daniel W. Stambovsky
Theses and Dissertations
A phase screen simulation experiment is designed and implemented to model radio occultation through sporadic-E ionospheric disturbances between a GPS transmitter operating at the L1 frequency and a second receiving satellite in low earth orbit (LEO). Simulations were made to test the linear relationship between plasma intensity and scintillation S4 index both posited (Arras and Wickert, 2018) and contended (Gooch et al., 2020) in previous literature. Results brought into question both the linear relationship and the use of S4 as a whole and an alternate metric was sought.
A Design For A Sustained Assessment Of Climate Forcing And Feedbacks Related To Land Use And Land Cover Change,
2020
Earth Resources Observation and Science (EROS)
A Design For A Sustained Assessment Of Climate Forcing And Feedbacks Related To Land Use And Land Cover Change, Thomas Loveland, Rezaul Mahmood
High Plains Regional Climate Center: Staff Publications
L and use and land cover change (LULCC) plays an important role in the climate system. Many studies have documented the impacts of LULCC on local, regional, and global climate. The National Climate Assessment Report (Melillo et al. 2014) identifies LULCC as a “cross cutting” issue of future climate change studies. This report, and the previous U.S. Climate Change Science Program strategic plan (2003), noted that land use and land cover (LULC) and its feedback is an important source of uncertainty within the climate system (Melillo et al. 2014). As a result, the report calls for a better understanding of …
Surface Reservoirs Dominate Dynamic Gas-Surface Partitioning Of Many Indoor Air Constituents,
2020
University of Toronto
Surface Reservoirs Dominate Dynamic Gas-Surface Partitioning Of Many Indoor Air Constituents, Chen Wang, Douglas B. Collins, Caleb Arata, Allen H. Goldstein, James M. Mattila, Delphine K. Farmer, Laura Ampollini, Peter F. Decarlo, Atila Novoselac, Marina E. Vance, William W. Nazaroff, Jonathan P.D. Abbatt
Faculty Journal Articles
Human health is affected by indoor air quality. One distinctive aspect of the indoor environment is its very large surface area that acts as a poorly characterized sink and source of gas-phase chemicals. In this work, air-surface interactions of 19 common indoor air contaminants with diverse properties and sources were monitored in a house using fast-response, on-line mass spectrometric and spectroscopic methods. Enhanced-ventilation experiments demonstrate that most of the contaminants reside in the surface reservoirs and not, as expected, in the gas phase. They participate in rapid air-surface partitioning that is much faster than air exchange. Phase distribution calculations are …
Modeling Of Ionospheric Responses To Atmospheric Acoustic And Gravity Waves Driven By The 2015 Nepal M W 7.8 Gorkha Earthquake,
2020
Embry-Riddle Aeronautical University
Modeling Of Ionospheric Responses To Atmospheric Acoustic And Gravity Waves Driven By The 2015 Nepal M W 7.8 Gorkha Earthquake, P. A. Inchin, J. B. Snively, M. D. Zettergren, A. Komjathy, O. P. Verkhoglyadova, S. Tulasi Ram
Publications
Near- and far-field ionospheric responses to atmospheric acoustic and gravity waves (AGWs) generated by surface displacements during the 2015 Nepal 7.8 Gorkha earthquake are simulated. Realistic surface displacements driven by the earthquake are calculated in three-dimensional forward seismic waves propagation simulation, based on kinematic slip model. They are used to excite AGWs at ground level in the direct numerical simulation of three-dimensional nonlinear compressible Navier-Stokes equations with neutral atmosphere model, which is coupled with a two-dimensional nonlinear multifluid electrodynamic ionospheric model. The importance of incorporating earthquake rupture kinematics for the simulation of realistic coseismic ionospheric disturbances (CIDs) is demonstrated and …
Air/Sea Transfer Of Highly Soluble Gases Over Coastal Waters,
2020
University of California, Irvine
Air/Sea Transfer Of Highly Soluble Gases Over Coastal Waters, J. G. Porter, Warren J. De Bruyn, S. D. Miller, E. S. Saltzman
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
The deposition of soluble trace gases to the sea surface is not well studied due to a lack of flux measurements over the ocean. Here we report simultaneous air/sea eddy covariance flux measurements of water vapor, sulfur dioxide (SO2), and momentum from a coastal North Atlantic pier. Gas transfer velocities were on average about 20% lower for SO2 than for H2O. This difference is attributed to the difference in molecular diffusivity between the two molecules (D SO 2/D H 2O = 0.5), in reasonable agreement with bulk parameterizations in air/sea gas …
Analysis Of Concurrent Backscatter Coefficients From In-Situ Cloud Probes And Airborne Lidar,
2020
University of North Dakota
Analysis Of Concurrent Backscatter Coefficients From In-Situ Cloud Probes And Airborne Lidar, Shawn Wagner, David J. Delene
Datasets
The North Dakota Citation Research Aircraft obtained measurements of anvil cirrus clouds over Florida during the summer of 2015 (CAPE2015). The Citation is fitted to take measurements of atmospheric variables (pressure, temperature, dew point, wind velocity, etc...) as well as cloud particle properties (concentration, size-distribution, water content, etc...). Data (at 1 Hz) is included from four flights occuring on 31 July 2015, 1 August 2015, and 2 August 2015. Cloud properties were measured by the Two-Dimensional Stereo probe (2D-S), the High-Volume Precipitation Spectrometer (HVPS3) probe and the Nevzorov probe. Additionally, particle data from the 2D-S and HVPS3 are combined to …
A 3-Year Sample Of Almost 1,600 Elves Recorded Above
South America By The Pierre Auger Cosmic-Ray
Observatory,
2020
Radboud University Nijmegen
A 3-Year Sample Of Almost 1,600 Elves Recorded Above South America By The Pierre Auger Cosmic-Ray Observatory, A. Aab, R. Engel, Gregory Snow, Pierre Auger Cosmic-Ray Observatory, 390 Co-Authors
Gregory Snow Publications
Elves are a class of transient luminous events, with a radial extent typically greater than 250 km, that occur in the lower ionosphere above strong electrical storms.We report the observation of 1,598 elves, from 2014 to 2016, recorded with unprecedented time resolution (100 ns) using the fluorescence detector (FD) of the Pierre Auger Cosmic-Ray Observatory. The Auger Observatory is located in the Mendoza province of Argentina with a viewing footprint for elve observations of 3 · 106 km2, reaching areas above the Pacific and Atlantic Oceans, as well as the Córdoba region, which is known for severe convective thunderstorms. Primarily …
