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Multi-Year Analysis of Short-Period Gravity Waves Over Alaska Under Various Stratospheric Weather Conditions
No full textAtmospheric gravity waves are major components of the dynamical atmosphere as they transfer large amounts of momentum and energy from the lower to the upper atmosphere [e.g. Fritts and Alexander, 2003]. In order to understand their influence on the state of the atmosphere, it is crucial to characterize these waves. The region where the waves have the most impact is in the upper atmosphere at altitudes between 80-110 km (~50-70 miles) , where the wave amplitude becomes so large that the wave breaks. This region is known as the mesopause , and is inherently difficult to observe. Fortunately, the mesopause region is also home to narrow layers producing very faint glow known as airglow. During night conditions, the nightglow can be detected with specially designed imaging systems measuring the intensity of the emitted light. As atmospheric gravity waves propagate through the airglow layers, they perturb these layers and imprint the signature during their passage. We present a three-year analysis of short period gravity waves measured by an airglow imager situated in Poker Flat, Alaska (65° N, 147° W). The imager is the cornerstone of the mesospheric airglow imaging and dynamics (MAID) project. This project is a collaborative effort between Utah Vally University, University of Alaska, Fairbanks and Utah State University, and employs the NICT Rayleigh Lidar System together with support observations from the co-located MF Radar and the NSF sponsored Poker Flat ISR.
The overarching goal of the project is to characterize the waves, their variability, and how stratospheric weather impacts the observed wave field. A recent study utilizing two years of data (2011-2012) showed a preponderance for eastward propagating waves, which is in stark contrast to other polar sites that have shown dominant westward motions. Furthermore, the study revealed a significant year to year variability in the observed phase speeds. In the study presented here, one year of additional data has been analyzed to further investigate the year to year variability and correlate the observed wave parameters to stratospheric weather phenomena including the Aleutian low, the polar vortex, and sudden stratospheric warming events
Climatology of Small-Scale Mesospheric Gravity Waves Observed Over Antarctica
No full textAs part of a collaborative research program between the British Antarctic Survey and Utah State University an all-sky CCD imager was deployed at Halley Station (75.5°S, 26.7°W), Antarctica and operated for two winter seasons (Apr. 2000 - Sept. 2001). The primary goal of this investigation was the determination of the characteristics and sources of short period (\u3c1 hour) gravity waves observed during the Antarctic winter in the absence of local tropospheric convection. In this study we have analyzed the spatial and temporal properties of 208 extensive wave events observed in the NIR OH emission (altitude ~87 km)
A Seasonal Investigation of Short Period Gravity Waves Over Hawaii
No full textThe Utah State University CEDAR Mesospheric Temperature Mapper (MTM) is a sensitive CCD Imager Currently operating at the US Air Force AMOS facility at the summit of Haleakala Crater, Maui, HI (20.8°N, 156°W) as part of the NSF/AFOSR Maui-MALT program.
The MTM measures two naturally occurring night-sky emissions: the near infrared OH(6, 2) Meinel and O2(0, 1) atmospheric band that are centered at mean altitudes ~87 and 94 km respectively. Each emission layer is ~ 8-10 km thick and these data provide a simple method of remote sensing gravity (buoyancy) wave propagation in the upper atmospheric region (80-100 km)
Simultaneous Mesospheric Wind, Gravity Wave and Temperature Measurements at Bear Lake Observatory, Utah (41.6°N)
No full textAs part of a collaborative research program between the Space Dynamics Laboratory of Utah State University and the University of Western Ontario a meteor radar was installed and operated at Bear Lake Observatory, Utah (41.6 N, 111.6 W) alongside several instruments including a multi-wavelength all-sky imager and an OH/O2 temperature mapper (MTM). Joint measurements were obtained over a six month period during the winter from October 2000 to March 2001. The meteor radar data have been analyzed to determine the zonal and meridional winds at MLT heights (~80-100 km) and to estimate the mesospheric temperature variability. The all-sky image data have been used to identify several prominent gravity wave events for the analysis of their intrinsic properties. This poster presents an initial comparison of the radar winds and wave signatures to set the scene for a quantitative study of mesospheric wave propagation at mid-latitudes
Remote Sensing Mesospheric Temperatures by SABER (on TIMED), SCIAMACHY (on ENVISAT) and Ground-Based Mesospheric Temperature Mapper: An Initial Comparison
No full textImplications of the 2023 Flood on the Lower Diamond Fork River, UT
Get PDFThe lower Diamond Fork River is located on publicly accessible land owned by the Utah Reclamation Mitigation and Conservation Commission and the United States Forest Service. It is located a 30 minute drive away from the Provo-Orem Metropolitan Area and the stream runs parallel to the Diamond Fork Road, giving anglers convenient access to several miles of publicly fishable stream. The focus of this study is the lower Diamond Fork River between US Highway 6 and the Diamond Fork Campground, UT (Figure 1)
Acceptance and Commitment Therapy (ACT) Among U.S. Veterans: A Systematic Review
No full textVeterans of the United States military represent a large sample of the population and a distinctive culture. Veterans have a high prevalence rate of a variety of psychological disorders and disabilities. Research on treatments that meet the needs of this culturally unique group is essential. Acceptance and Commitment Therapy (ACT) may meet this need with its unified treatment approach and its focus on functioning rather than diagnosis. In this study we examine the current state of the literature of ACT for U.S. Veterans. A systematic review of 249 papers found 34 unique relevant studies involving 21 single arm studies, eight randomized clinical trials, two non-randomized controlled trials, and three case studies that met inclusion criteria. Overall, results suggest ACT is a promising intervention for Veterans across multiple conditions (e.g., anxiety disorders, depression, chronic pain) as well as intervention delivery (in-person and telehealth) and type (group and individual therapy). Limitations highlighted include recruitment methods of studies included, lack of active control conditions, and the limited number of randomized trials. Future researchers should continue to examine which presentations respond to ACT and seek to understand what types of adaptations may be necessary to increase the effectiveness of ACT for U.S. Veterans
Bacterial Emission Factors: A Foundation for the Terrestrial-Atmospheric Modeling of Bacteria Aerosolized by Wildland Fires
No full textWildland fire is a major global driver in the exchange of aerosols between terrestrial environments and the atmosphere. This exchange is commonly quantified using emission factors or the mass of a pollutant emitted per mass of fuel burned. However, emission factors for microbes aerosolized by fire have yet to be determined. Using bacterial cell concentrations collected on unmanned aircraft systems over forest fires in Utah, USA, we determine bacterial emission factors (BEFs) for the first time. We estimate that 1.39 × 1010 and 7.68 × 1011 microbes are emitted for each Mg of biomass consumed in fires burning thinning residues and intact forests, respectively. These emissions exceed estimates of background bacterial emissions in other studies by 3–4 orders of magnitude. For the ~2631 ha of similar forests in the Fishlake National Forest that burn each year on average, an estimated 1.35 × 1017 cells or 8.1 kg of bacterial biomass were emitted. BEFs were then used to parametrize a computationally scalable particle transport model that predicted over 99% of the emitted cells were transported beyond the 17.25 x 17.25 km model domain. BEFs can be used to expand understanding of global wildfire microbial emissions and their potential consequences to ecosystems, the atmosphere, and humans
Non-Random Sampling Measures the Occurrence but Not the Strength of a Textbook Trophic Cascade
No full textAlthough sampling the five tallest young aspen in a stand is useful for detecting the occurrence of any aspen recruitment, this technique overestimates the population response of aspen to wolf reintroduction. Our original conclusion that random sampling described a trophic cascade that was weaker than the one described by non-random sampling is unchanged
Developing Educational Tools for Sustainable Stormwater Management
Get PDFRapid population growth and development in Western states are exerting strain on the region’s limited water resources. Urbanization exacerbates this issue by increasing impervious surfaces, limiting infiltration of precipitation during storm events and snowmelt, which results in changes to hydrologic conditions with higher runoff volumes and higher peak flows. Stormwater transports pollutants as it flows across impervious surfaces, discharging high volumes of runoff and elevated loads of urban contaminants into receiving waters. The amount of pollution entering waterways continually increases as urban areas expand. Utah is currently experiencing a rapid transition from undeveloped to developed landscapes, necessitating the implementation of sustainable stormwater management practices.
This project addresses the need for resources to support the implementation of low-impact development (LID) in Utah. Most available resources are designed for humid or mesic regions and lack specific guidelines for optimizing ecosystem services of LID in arid regions. We developed a series of tailored educational resources and management tools to empower professionals in stormwater management with the knowledge and tools to navigate evolving water quality challenges linked to urban development and runoff. These materials include a planting guide for low-impact development, a comprehensive website, and fact sheets about managing stormwater for multiple sectors. Empowering communities and professionals with educational resources and best practices is essential for maintaining compliance with stormwater discharge standards and curbing the impacts of urban pollution before reaching critical water quality and habitat impairment. Utah is strategically positioned to proactively address increasing development and prevent significant degradation to state water bodies