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- Creators: Debussy, Claude, 1862-1918
Description
Dust devils have proven to be commonplace on Mars, although their occurrence is unevenly distributed across the surface. They were imaged or inferred by all six successful landed spacecraft: the Viking 1 and 2 Landers (VL-1 and VL-2), Mars Pathfinder Lander, the Mars Exploration Rovers Spirit and Opportunity, and the Phoenix Mars Lander. Comparisons of dust devil parameters were based on results from optical and meteorological (MET) detection campaigns. Spatial variations were determined based on comparisons of their frequency, morphology, and behavior. The Spirit data spanning three consecutive martian years is used as the basis of comparison because it is the most extensive on this topic. Average diameters were between 8 and 115 m for all observed or detected dust devils. The average horizontal speed for all of the studies was roughly 5 m/s. At each site dust devil densities peaked between 09:00 and 17:00 LTST during the spring and summer seasons supporting insolation-driven convection as the primary formation mechanism. Seasonal number frequency averaged ~1 dust devils/ km2/sol and spanned a total of three orders of magnitude. Extrapolated number frequencies determined for optical campaigns at the Pathfinder and Spirit sites accounted for temporal and spatial inconsistencies and averaged ~19 dust devils/km2/sol. Dust fluxes calculated from Pathfinder data (5x10-4 kg/m2/s and 7x10-5 kg/m2/s) were well with in the ranges calculated from Spirit data (4.0x10-9 to 4.6x10-4 kg/m2/s for Season One, 5.2x10-7 to 6.2x10-5 kg/m2/s during Season Two, and 1.5x10-7 to 1.6x10-4 kg/m2/s during Season Three). Based on the results a campaign is written for improvements in dust devil detection at the Mars Science Laboratory's (MSL) site. Of the four remaining candidate MSL sites, the dusty plains of Gale crater may potentially be the site with the highest probability of dust devil activity.
ContributorsWaller, Devin (Author) / Greeley, Ronald (Thesis advisor) / Christensen, Philip R. (Philip Russel) (Committee member) / Cerveny, Randall (Committee member) / Arizona State University (Publisher)
Created2011
ContributorsDebussy, Claude, 1862-1918 (Composer)
ContributorsDebussy, Claude, 1862-1918 (Composer)
ContributorsDebussy, Claude, 1862-1918 (Composer)
ContributorsDebussy, Claude, 1862-1918 (Composer)
ContributorsDebussy, Claude, 1862-1918 (Composer)
Description
Arizona’s population has been increasing quickly in recent decades and is expected to rise an additional 40%-80% by 2050. In response, the total annual energy demand would increase by an additional 30-60 TWh (terawatt-hours). Development of solar photovoltaic (PV) can sustainably contribute to meet this growing energy demand.
This dissertation focuses on solar PV development at three different spatial planning levels: the state level (state of Arizona); the metropolitan level (Phoenix Metropolitan Statistical Area); and the city level. At the State level, this thesis answers how much suitable land is available for utility-scale PV development and how future land cover changes may affect the availability of this land. Less than two percent of Arizona's land is considered Excellent for PV development, most of which is private or state trust land. If this suitable land is not set-aside, Arizona would then have to depend on less suitable lands, look for multi-purpose land use options and distributed PV deployments to meet its future energy need.
At the Metropolitan Level, ‘agrivoltaic’ system development is proposed within Phoenix Metropolitan Statistical Area. The study finds that private agricultural lands in the APS (Arizona Public Service) service territory can generate 3.4 times the current total energy requirements of the MSA. Most of the agricultural land lies within 1 mile of the 230 and 500 kV transmission lines. Analysis shows that about 50% of the agricultural land sales would have made up for the price of the sale within 2 years with agrivoltaic systems.
At the City Level, the relationship between rooftop PV development and demographic variables is analyzed. The relationship of solar PV installation with household income and unemployment rate remain consistent in cities of Phoenix and Tucson while it varies with other demographic parameters. Household income and owner occupancy shows very strong correlations with PV installation in most cities. A consistent spatial pattern of rooftop PV development based on demographic variables is difficult to discern.
Analysis of solar PV development at three different planning levels would help in proposing future policies for both large scale and rooftop solar PV in the state of Arizona.
This dissertation focuses on solar PV development at three different spatial planning levels: the state level (state of Arizona); the metropolitan level (Phoenix Metropolitan Statistical Area); and the city level. At the State level, this thesis answers how much suitable land is available for utility-scale PV development and how future land cover changes may affect the availability of this land. Less than two percent of Arizona's land is considered Excellent for PV development, most of which is private or state trust land. If this suitable land is not set-aside, Arizona would then have to depend on less suitable lands, look for multi-purpose land use options and distributed PV deployments to meet its future energy need.
At the Metropolitan Level, ‘agrivoltaic’ system development is proposed within Phoenix Metropolitan Statistical Area. The study finds that private agricultural lands in the APS (Arizona Public Service) service territory can generate 3.4 times the current total energy requirements of the MSA. Most of the agricultural land lies within 1 mile of the 230 and 500 kV transmission lines. Analysis shows that about 50% of the agricultural land sales would have made up for the price of the sale within 2 years with agrivoltaic systems.
At the City Level, the relationship between rooftop PV development and demographic variables is analyzed. The relationship of solar PV installation with household income and unemployment rate remain consistent in cities of Phoenix and Tucson while it varies with other demographic parameters. Household income and owner occupancy shows very strong correlations with PV installation in most cities. A consistent spatial pattern of rooftop PV development based on demographic variables is difficult to discern.
Analysis of solar PV development at three different planning levels would help in proposing future policies for both large scale and rooftop solar PV in the state of Arizona.
ContributorsMajumdar, Debaleena (Author) / Pasqualetti, Martin J (Thesis advisor) / Pijawka, David (Committee member) / Cerveny, Randall (Committee member) / Ehlenz, Meagan (Committee member) / Arizona State University (Publisher)
Created2018
Description
The El Niño Southern Oscillation (ENSO) consists of a linkage between changes in sea-surface temperatures and atmospheric pressure across the Tropical Pacific. ENSO encompasses three phases: neutral events, warm/El Niño events in which sea-surface temperatures are warmer-than-normal and the pressure gradient decreases across the Equatorial Pacific, and cold/La Niña events in which Tropical Pacific sea-surface temperatures are cooler-than-normal and the pressure gradient increases. Previous studies have determined a connection between variations in ENSO phase and weather patterns across the globe, focusing particularly on surface temperature and precipitation patterns in the United States. However, little research exists that attempts to link changes in ENSO phase with severe weather in Arizona. Therefore, in this study, I analyzed how variations in ENSO phase affect the frequency, intensity, and spatial distribution of four types of severe weather from 1959 to 2016 in Arizona, including a) tornado events, b) severe thunderstorm wind events, c) hail events, and d) heavy rain and flash flood events. I collected data on the Oceanic Niño Index (ONI), a measure of ENSO, as well as storm reports for each severe weather phenomenon dating back to 1959. Then, I analyzed the frequency of each Arizona severe weather event type within each of the twelve annual months and over the entire study period. I also analyzed mean intensity values (Fujita/Enhanced Fujita Scale rating, path width, and path length for tornadoes; hail diameter in millimeters for hail; and wind gust speed for severe thunderstorm wind events) for each severe weather phenomenon, excluding the heavy rain and flash flood events. Finally, I used the Mean Center and Directional Distribution tools in ArcGIS to determine variations in the spatial distribution and mean centers between each ENSO phase for each severe weather event type. I found that ENSO phase, particularly La Niña, does impact the frequency and intensity of tornadoes, hail, thunderstorm wind, and heavy rain/flash flood events in Arizona. However, it appears that ENSO does not affect the spatial distribution of these Arizona severe weather phenomena. These findings attempt to fill in the gap in the literature and could help meteorologists better forecast changes in Arizona severe weather, in turn allowing Arizonans to better prepare for and mitigate the effects of severe weather across the state.
ContributorsGreenwood, Trey Austin (Author) / Cerveny, Randall (Thesis director) / Balling, Robert (Committee member) / School of Geographical Sciences and Urban Planning (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
The Mid-South region, which consists of west Tennessee, northeast Arkansas, north Mississippi, and the Missouri bootheel, is one of many areas in the United States that frequently faces the threats to life and property posed by tornadoes. Forecasting the occurrence of tornadoes is arguably the biggest challenge for meteorologists responsible for the region. This study analyzes synoptic scale weather conditions associated with tornadoes in the Mid-South with the hopes of identifying patterns conducive to tornadic activity and that these patterns can be used to better forecast potential tornado days. It is hypothesized that patterns associated with tornado formation can be identified and that certain patterns may be more favorable to stronger tornadoes or tornado outbreaks than others.
To find these patterns, I analyzed surface and upper air features were analyzed on days where multiple tornadoes occurred from January 1999 to March 2018. Specifically, the surface low pressure, 500hPa trough, and 850 and 300hPa jets were analyzed. Using a floating nine point grid system, I identified the location of the Mid-South in relation to the feature. In the end, eight patterns of similar grid locations were identified to be related to tornado days. For example, the Mid-South was frequently to the southeast of the surface low. However, no correlation appears to exist between the patterns and the number or intensity of tornadoes. It is recommended that in the future these patterns be tested as a forecast method and/or compared to non-tornado days to verify that they are valid tools.
To find these patterns, I analyzed surface and upper air features were analyzed on days where multiple tornadoes occurred from January 1999 to March 2018. Specifically, the surface low pressure, 500hPa trough, and 850 and 300hPa jets were analyzed. Using a floating nine point grid system, I identified the location of the Mid-South in relation to the feature. In the end, eight patterns of similar grid locations were identified to be related to tornado days. For example, the Mid-South was frequently to the southeast of the surface low. However, no correlation appears to exist between the patterns and the number or intensity of tornadoes. It is recommended that in the future these patterns be tested as a forecast method and/or compared to non-tornado days to verify that they are valid tools.
ContributorsWanless, Anna Cecilia (Author) / Cerveny, Randall (Thesis director) / Svoma, Bohumil (Committee member) / School of Geographical Sciences and Urban Planning (Contributor, Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
This thesis examines the synoptic characteristics associated with ozone exceedance events in Arizona during the time period of 2011 to 2013. Finding explanations and sources to the ground level ozone in this state is crucial to maintaining the state’s adherence to federal air quality regulations. This analysis utilizes ambient ozone concentration data, surface meteorological conditions, upper air analyses, and HYSPLIT modeling to analyze the synoptic characteristics of ozone events. Based on these data and analyses, five categories were determined to be associated with these events. The five categories all exhibit distinct upper air patterns and surface conditions conducive to the formation of ozone, as well as distinct potential transport pathways of ozone from different nearby regions. These findings indicate that ozone events in Arizona can be linked to synoptic-scale patterns and potential regional transport of ozone. These results can be useful in the forecasting of high ozone pollution and influential on the legislative reduction of ozone pollution.
ContributorsWood, Jessica (Author) / Cerveny, Randall (Thesis advisor) / Georgescu, Matei (Committee member) / Brazel, Anthony (Committee member) / Arizona State University (Publisher)
Created2016