In this physically-based tornado simulation, the tornado-scale approach techniques are applied to simulate the tornado formation environment. The three-dimensional Navier-Stokes equations for incompressible viscous fluid flows are used to model the tornado dynamics. The boundary conditions applied in this simulation lead to rotating and uplifting flow movement as found in real tornadoes and tornado research literatures. Moreover, a particle system is incorporated with the model equation solutions to model the irregular tornado shapes. Also, together with appropriate boundary conditions, varied particle control schemes produce tornadoes with different shapes. Furthermore, a modified metaball scheme is used to smooth the density distribution. Texture mapping, antialising, animation and volume rendering are applied to produce realistic visual results. The rendering algorithm is implemented in OpenGL.

Several programs exist today for calculating aerodynamic coefficients that with some simplificationsprovide fast approximations of the values for a real aircraft.Four different programs were analyzed for this report: Tornado, AVL, PANAIR and a handbook-typepreliminary method. In addition, ANSYS CFX was used for airfoil validation. For calculation of the zerolift drag, an approximation was computed in order to calculate the remaining values that were notcalculated by the software: drag contribution for fuselages, nacelles and some horizontal stabilizersand fins.Different types of aircraft were selected for trial: two commercial aircraft (Boeing 747-100 and 777-300), a TF-8A research airplane (with area rule application: some additions were made to the fuselageto prevent large variations in the cross-section when the contribution of the wing is added), a LockheedConstellation C-69 used as a military cargo airplane, a Boeing Stratocruiser used by the USAF withtwo configurations (basic and bomber), and an Aero Commander 680 Super, similar to a Cessna 162.Two airfoils (NACA2412, 0012) were also analyzed, to investigate the limitations of software designedfor three-dimensional calculations.The accuracy of the results showed that the validity of the software depends on the planform of theaircraft, as well as the simulation parameters Mach number and Reynolds number. The shape of thewing caused some of the methods to have serious difficulties in converging to valid results, orincreased the simulation time beyond acceptable limits. / Numera finns det olika program för beräkning av de aerodynamiska koefficienterna från en modellmed vissa förenklingar som ger en snabb approximation av värdena för ett verkligt flygplan.Fyra olika program har analyserats för denna rapport: Tornado, AVL, PANAIR och en handbokbaserad preliminär metod. Dessutom användes ANSYS CFX för validering av vingprofiler . Vidberäkningen av noll-lyft motståndet, en approximation användes för de återstående delarna som inteberäknas av de andra metoderna: motståndsbidraget från flygkroppar, gondoler och vissa horisontellastabilisatorer och fenor.Olika flygplaner har testats: två trafikflygplan (Boeing 747-100 och 777-300), ett TF-8Aforskningsflygplan (med area regel användning: några tillägg gjordes på flygkroppen för att tvärsnitteninte har stora variationer när bidraget från vingen läggas), ett Lockheed Constellation C-69, ett BoeingStratocruiser som används av USAF i två konfigurationer (den vanliga och bombplan), och ett AeroCommander 680 Super, som liknar ett Cessna 162. Två vingprofiler (NACA 2412, 0012) analyseradesockså, för att kontrollera begränsningarna av programmen avsedd för tredimensionella beräkningar.Riktigheten av resultaten visade att giltigheten av programmen beror på formen av flygplanernasvingar, samt de simulationernas parametrar: Mach nummer och Reynolds nummer. Formen på vingenorsakade några av de metoderna att ha stora svårigheter med konvergensen till giltiga resultat, ellerökat simulering tid över acceptabla gränser.

In this physically-based tornado simulation, the tornado-scale approach techniques are applied to simulate the tornado formation environment. The three-dimensional Navier-Stokes equations for incompressible viscous fluid flows are used to model the tornado dynamics. The boundary conditions applied in this simulation lead to rotating and uplifting flow movement as found in real tornadoes and tornado research literatures. Moreover, a particle system is incorporated with the model equation solutions to model the irregular tornado shapes. Also, together with appropriate boundary conditions, varied particle control schemes produce tornadoes with different shapes. Furthermore, a modified metaball scheme is used to smooth the density distribution. Texture mapping, antialising, animation and volume rendering are applied to produce realistic visual results. The rendering algorithm is implemented in OpenGL.

During the early evening of 22 June 2007, a violent tornado impacted the western edge of Elie, Manitoba. This was Canada’s first documented F5 tornado. Three primary research questions were posed: (1) What were the pre-storm environmental conditions on 22 June 2007? (2) How did the storm and associated tornado evolve? (3) How does this event compare to other major tornadic events in Canada and the U.S.? The tornado passed in close proximity to a fixed-location Environment Canada Doppler radar at Woodlands, Manitoba. This allowed for a detailed examination of local mesoscale boundaries that were present prior to and during the event. The Elie tornado was rare in the fact that it looped three times within the main track and it moved approximately 5 km during its 40 minute lifetime causing F5 damage to homes and structures when it was an estimated 50 m wide.

During the early evening of 22 June 2007, a violent tornado impacted the western edge of Elie, Manitoba. This was Canada’s first documented F5 tornado. Three primary research questions were posed: (1) What were the pre-storm environmental conditions on 22 June 2007? (2) How did the storm and associated tornado evolve? (3) How does this event compare to other major tornadic events in Canada and the U.S.? The tornado passed in close proximity to a fixed-location Environment Canada Doppler radar at Woodlands, Manitoba. This allowed for a detailed examination of local mesoscale boundaries that were present prior to and during the event. The Elie tornado was rare in the fact that it looped three times within the main track and it moved approximately 5 km during its 40 minute lifetime causing F5 damage to homes and structures when it was an estimated 50 m wide.

abstract: Remote sensing has demonstrated to be an instrumental tool in monitoring land changes as a result of anthropogenic change or natural disasters. Most disaster studies have focused on large-scale events with few analyzing small-scale disasters such as tornadoes. These studies have only provided a damage assessment perspective with the continued need to assess reconstruction. This study attempts to fill that void by examining recovery from the 1999 Moore, Oklahoma Tornado utilizing Landsat TM and ETM+ imagery. Recovery was assessed for 2000, 2001 and 2002 using spectral enhancements (vegetative and urban indices and a combination of the two), a recovery index and different statistical thresholds. Classification accuracy assessments were performed to determine the precision of recovery and select the best results. This analysis proved that medium resolution imagery could be used in conjunction with geospatial techniques to capture recovery. The new indices, Shortwave Infrared Index (SWIRI) and Coupled Vegetation and Urban Index (CVUI), developed for disaster management, were the most effective at discerning reconstruction using the 1.5 standard deviation threshold. Recovery rates for F-scale damages revealed that the most incredibly damaged areas associated with an F5 rating were the slowest to recover, while the lesser damaged areas associated with F1-F3 ratings were the quickest to rebuild. These findings were consistent for 2000, 2001 and 2002 also exposing that complete recovery was never attained in any of the F-scale damage zones by 2002. This study illustrates the significance the biophysical impact has on recovery as well as the effectiveness of using medium resolution imagery such as Landsat in future research. / Dissertation/Thesis / M.A. Geography 2011

Geographies of Responsibility: The Cultural Logic of 21st Century Weather Emergencies analyzes the role of narrative in contemporary severe weather events. The speed and diversity of media through which we now communicate "the weather" significantly impact how U.S. communities experience these events and their possible social, cultural, and political meanings. This project explores four weather emergencies, covering physical geographies of the far northwest, Great Plains, mid-Atlantic, and Caribbean, that were circulated and reframed via a range of media--from newspapers to television, social, and new media--who discussed these events, and to what ends. Chapter 1 examines reporting on the 2004 Alaska wildfires directed at U.S. national and Alaska state communities to explore the importance of the "nation" as a continuing relevant relative spatial scale. Chapter 2 investigates the 2007 Greensburg tornado and subsequent "green" (re)development of the town. Chapter 3 analyzes the 2010 "Snowmageddon" blizzards in Washington, D.C., which initiated "playful" acts that highlighted how urban economic realities and historical social geographies of race are embedded in particular urban sites. Chapter 4 explores the 2010 Haiti earthquake, which evoked economies of responsibility across multiple scales of mobilization that reiterated the cultural and historical "weather map" laid down by Hurricane Katrina. These mass mediated weather events each mobilized attention and response through narratives that evoked an emergency to communities across multiple geographic scales put into relationships with one another through storylines far more complex than an analysis of how "global" and local weather systems co-create each other.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18640号 / 理博第4019号 / 新制||理||1579(附属図書館) / 31554 / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)教授 石川 裕彦, 准教授 林 泰一, 教授 余田 成男 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

Tornadoes are always dangerous, but inside a motor vehicle they are especially problematic due to an automobile’s smaller size and structure. Tornado fatalities in motor vehicles have not decreased in recent years despite downward trends in total tornado fatalities. Receiving tornado warnings is difficult inside a motor vehicle, particularly when alone in the vehicle. Controlled access highways are also difficult places to find shelter as access is limited to interchanges, while buildings at interchanges may not be able to withstand an intense tornado. Electronic signs and audible messages on mobile communications devices are the most suitable technologies available for reaching motorists. At each interchange, shelters capable of withstanding a violent tornado should be constructed or retrofitted, allowing motorists – and nearby residents – a safe place to shelter nearby. Constructing such shelters will take considerable time and significant cost but will go a long way towards the goal of a Weather-Ready Nation.

One of the greatest natural hazards that is faced with in much of the United States are tornadoes. Despite improvements in the warning processes, the risk of significant loss of life remains high. That is particularly true with vulnerable communities which have higher proportions of mobile homes; however, violent tornadoes are very difficult to manage in permanent homes or buildings as well. As a result, tornado shelters have been built in some communities and have become available to the public. However, their presence is intermittent, and there are many tornado-prone areas that lack such shelters. After a public survey, it was found that there was unmet demand for tornado shelters and, at least in the most extreme circumstances, a large percentage of the population would be willing to utilize such. It was also found that better communication of tornado shelters would increase utilization rates either in circumstances where they already exist or where the need exists. Some residents, particularly those in mobile homes, were likely to utilize shelters more frequently, which increased their need to an even greater extent. Once both the public and broadcast meteorologists were surveyed, it was found that the public was strongly supportive of mobile applications about tornado shelters in their area, and local television sources and the websites and applications related to those stations were also popular sources. Broadcast meteorologists in the Deep South in particular mentioned the need for more shelters and advocated construction, but not as much in other regions. They mentioned that mobile apps would be quite useful for the public to locate shelters. A case study in the context of the concurrent COVID-19 pandemic (knowing that crowded spaces was not a desirable situation amidst the pandemic) found that shelters were still potentially useful with mitigation. Those concurrent hazards made for a more challenging study and proved to be a valuable case study in tornado sheltering. The results found that it was possible to attenuate both threats provided that careful planning and actions were undertaken. As a result, both short-term and long-term recommendations were suggested which may also be useful in future pandemic situations.