Eliminating the major tornado threat in Tornado Alley

2014 ◽  
Vol 28 (22) ◽  
pp. 1450175 ◽  
Author(s):  
R. Tao
Keyword(s):  
Air Flow ◽  
Vertical Axis ◽  
South Texas ◽  
Lower Atmosphere ◽  
Air Mass ◽  
Cold Air ◽  
American Midwest ◽  
The Third ◽  
Tornado Outbreaks ◽  
East West

The 2013 devastating tornadoes in Oklahoma, Illinois and other states in Tornado Alley raise an important question: Can we do something to eliminate the major tornado threats in Tornado Alley? Violent tornadoes in Tornado Alley start from the clash-between northbound warm air flow and southbound cold air flow. As there is no mountain in Tornado Alley ranging from west to east to weaken or block the air flows, some clashes are violent, creating vortex turbulence called supercells. These supercells are initially in horizontal spinning motion at the lower atmosphere and then tilt as the air turns to rise in the storm's updraft, creating a component of spin around a vertical axis. About 30% of supercells develop into tornadoes, causing tremendous damages. Here we show that if we build three east–west great walls in the American Midwest, 300 m high and 50 m wide, one in North Dakota, one passing Oklahoma to east and the third one in the south Texas and Louisiana, we will weaken or block such air mass clashes and therefore diminish the major tornado threat in the Tornado Alley forever. We may also first build such great walls locally at some areas with frequent devastating tornado outbreaks and then gradually extend them.

Can we eliminate major tornadoes in Tornado Alley? — Response to the Comments

2014 ◽  
Vol 28 (29) ◽  
pp. 1475005
Author(s):  
R. Tao
Keyword(s):  
Wind Shear ◽  
Laboratory Experiments ◽  
Fluid Model ◽  
Air Flow ◽  
Inviscid Fluid ◽  
Air Mass ◽  
Turbulent Eddies ◽  
Air Density ◽  
Basic Physics ◽  
East West

Dahl and Markowski are wrong and misleading to claim that the major tornadoes in USA Tornado Alley are not related to the collisions between northbound warm air flow and southbound cold air flow. In addition, they use incompressible and inviscid fluid model for atmosphere in their simulations about the interaction between air wind and the wall. Such approach ignores the basic physics and thus cannot reach any meaningful results. As air is compressible, the collision between the wind and wall will compress air, eventually lead the air density to decrease fast with the height and make the air flow stratified. The viscosity will produce wind shear, turbulent eddies and greatly reduce the wind's forwarding speed. Laboratory experiments and the Nature have all shown that hills with height about 300 m will not block winds completely to change the climate, but can effectively reduce the wind speed, weaken the air mass collisions and eliminate the major tornadoes. All these strongly support the theory that building east–west ranged walls of 300 m high and 50 m wide will eliminate major tornado threat in Tornado Alley.

The Third East-West Philosophers' Conference

1960 ◽  
Vol 57 (1) ◽  
pp. 24-37
Author(s):  
Paul W. Kurtz ◽  
Keyword(s):  
The Third ◽  
East West

Americans in Britain's Backyard: The Railway Era in Upper Canada, 1850–1880

1981 ◽  
Vol 55 (3) ◽  
pp. 314-336 ◽  
Author(s):  
Peter Baskerville
Keyword(s):  
New England ◽  
Small Population ◽  
Financial Control ◽  
Upper Canada ◽  
Atlantic Seaboard ◽  
American Midwest ◽  
Middle Atlantic ◽  
American Cities ◽  
East West ◽  
Eastern Seaboard

Canadian lines that were spreading out over what would become the Province of Ontario looked forward, in the years before the American Civil War, to becoming important east-west carriers between the rapidly growing American cities of the eastern seaboard and the still-new cities of the American Midwest. Canada's small population and undeveloped industry would force her railroads to rely heavily on traffic going from one American city to another. Lines like the Grand Trunk and the Great Western struggled desperately therefore, to avoid American financial control. With the help of British capital, they succeeded. But America's contribution to Canadian railroading ran much deeper than money. Dominating the skilled engineers and experienced construction contractors who came from south of the border was more difficult for Canadian directors to manage. In the end, however, it was the early failure of top Canadian management to bury their rivalries, ignore their English creditors, emulate Americans like Vanderbilt, Thomson, and Garrett, and consolidate into an integrated line between New England, the Middle Atlantic seaboard, and the Midwest that doomed their railroads to becoming, as one Canadian put it, “side streets to the trade thoroughfare.”

The Third Bosporus Bridge — the Aerodynamic Stability of the Steel Segments During the Lifting

2019 ◽  
Author(s):  
Vincent de Ville de Goyet ◽  
Yves Duchêne
Keyword(s):  
Vertical Axis ◽  
Longitudinal Axis ◽  
The Black Sea ◽  
Span Length ◽  
Geometrical Configuration ◽  
Aerodynamic Stability ◽  
The Third ◽  
The North ◽  
Torsional Instability ◽  
Main Cables

<p>The Third Bosporus Bridge is a suspendion bridge with a main span length of 1 408 m and a total length of 2 408 m located at the north of Istanbul near the Black Sea.</p><p>The main span is partially suspended at the pylons by stiffening cables and at the main cables with vertical hangers (Fig.1‐2). The deck is 58.8 m wide. But contrary to a classical arrangement, the transversal distance between the vertical hangers, in the suspended zone, is only 13.50 m. Due to this geometrical configuration of the vertical hangers, it was necessary to verify the risk of aeroelastic instabilities of steel segments of the deck during its lifting: risk of a torsional instability around the longitudinal axis but also around the vertical axis. Countermeasures have been proposed and adopted to suppress these risks.</p>

scholarly journals A three-dimensional theory of wind pumping

1991 ◽  
Vol 37 (125) ◽  
pp. 89-96 ◽  
Author(s):  
Garry K. C. Clarke ◽  
Edwin D. Waddington
Keyword(s):  
Heat Source ◽  
Surface Pressure ◽  
Air Flow ◽  
Pressure Fluctuations ◽  
Normal Component ◽  
Three Dimensional ◽  
Lower Atmosphere ◽  
Dimensional Theory ◽  
Theoretical Formulation ◽  
Near Surface

AbstractQuantitative understanding of the processes that couple the lower atmosphere to the upper surface of ice sheets is necessary for interpreting ice-core records. Of special interest are those processes that involve the exchange of energy or atmospheric constituents. One such process, wind pumping, entails both possibilities and provides a possible mechanism for converting atmospheric kinetic energy into a near-surface heat source within the firn layer. The essential idea is that temporal and spatial variations in surface air pressure, resulting from air motion, can diffuse into permeable firn by conventional Darcy flow. Viscous friction between moving air and the solid firn matrix leads to energy dissipation in the firn that is equivalent to a volumetric heat source.Initial theoretical work on wind pumping was aimed at explaining anomalous near-surface temperatures measured at sites on Agassiz Ice Cap, Arctic Canada. A conclusion of this preliminary work was that, under highly favourable conditions, anomalous warming of as much as 2°C was possible. Subsequent efforts to confirm wind-pumping predictions suggest that our initial estimates of the penetration depth for pressure fluctuations were optimistic. These observations point to a deficiency of the initial theoretical formulation — the surface-pressure forcing was assumed to vary temporally, but not spatially. Thus, within the firn there was only a surface-normal component of air flow. The purpose of the present contribution is to advance a three-dimensional theory of wind pumping in which air flow is driven by both spatial and temporal fluctuations in surface pressure. Conclusions of the three-dimensional analysis are that the penetration of pressure fluctuations, and hence the thickness of the zone of frictional interaction between air and permeable firn, is related to both the frequency of the pressure fluctuations and to the spatial coherence length of turbulence cells near the firn surface.

An air mass-derived cool season climatology of synoptically forced Appalachian cold-air damming

2017 ◽  
Vol 38 (2) ◽  
pp. 530-542 ◽  
Author(s):  
Andrew W. Ellis ◽  
Michael L. Marston ◽  
Daniel A. Nelson
Keyword(s):  
Cool Season ◽  
Air Mass ◽  
Cold Air

Capturing Cold-Air Flow Using Thermal Imaging

2015 ◽  
Vol 157 (2) ◽  
pp. 321-332 ◽  
Author(s):  
A. Martina Grudzielanek ◽  
Jan Cermak
Keyword(s):  
Thermal Imaging ◽  
Air Flow ◽  
Cold Air

scholarly journals Improving the efficiency of carousel wind turbine using aerodynamic shield

2021 ◽  
Vol 2119 (1) ◽  
pp. 012093
Author(s):  
A F Serov ◽  
V N Mamonov ◽  
A D Nazarov ◽  
N B Miskiv
Keyword(s):  
Kinetic Energy ◽  
Flow Velocity ◽  
Air Flow ◽  
Cylindrical Body ◽  
Vertical Axis ◽  
Rotor Blades ◽  
Heat Generator ◽  
Axis Of Rotation ◽  
Wheel Torque ◽  
Air Flow Velocity

Abstract The problem of increasing the efficiency of using the oncoming air flow for a wind wheel with a vertical axis of rotation, which is a mechanical drive of the wind heat generator, is considered. It is proposed to increase the efficiency of the device by installing an aerodynamic shield for the air flow oncoming the wind wheel. Such a shield is a cylindrical body in which a heat generator is placed. The shield creates an effect of confuser, leading to an increase in the speed and, consequently, in the kinetic energy of the air flow acting on the rotor blades. It is shown experimentally that the presence of an aerodynamic shield under the conditions of the experiments carried out at an incoming air flow velocity of ~ 1 m/s leads to a practical doubling of the wind wheel torque.

Range Forage Production and Consumption Following Aerial Spraying of Mixed Brush

Weed Science ◽  
1977 ◽  
Vol 25 (1) ◽  
pp. 48-54 ◽  
Author(s):  
C.J. Scifres ◽  
G.P. Durham ◽  
J.L. Mutz
Keyword(s):  
South Texas ◽  
Forage Production ◽  
Direct Function ◽  
Native Grass ◽  
The Third ◽  
Production And Consumption ◽  
Anisic Acid ◽  
Use Efficiency ◽  
Second Year ◽  
Brush Control

Production of native grasses following aerial application of 1.12 kg/ha of 2.4.5-T ((2,4,5-trichlorophenoxy)acetic acid), 2,4,5-T + dicamba (3,6-dichloro-o-anisic acid), or 2,4,5-T + picloram (4-amino-3,5,6-trichloropicolinic acid) (1:) to a south Texas mixed-brush (Prosopis-Acacia) community was significantly increased by all herbicide treatments the year of application, by the herbicide combinations during the second year, but only by 2,4,5-T + picloram the third year after treatment. Moisture-use efficiency based on kg/ha native grass produced/cm precipitation was greastest where the herbicide combinations were applied. Defoliation of woody plants in years of above-average rainfall resulted in favorable grass production responses regardless of herbicide(s). However, range improvement over the 3-yr of study was dependent on maintenance of herbicide effectiveness, especially control of underbrush which resulted only where 2,4,5-T + picloram were applied. Consumption of native grass was a direct function of availability in response to brush control as augmented by rainfall. Forb production was reduced by all herbicides the year of treatment and by 2,4,5-T + picloram the year following application, but was not reduced by any treatment during the third growing season.

scholarly journals Southeastern U.S. Tornado Outbreak Likelihood Using Daily Climate Indices

2020 ◽  
Vol 33 (8) ◽  
pp. 3229-3252
Author(s):  
Matthew C. Brown ◽  
Christopher J. Nowotarski
Keyword(s):  
Time Scales ◽  
North Atlantic ◽  
Climate Indices ◽  
Regional Environment ◽  
Self Organizing Maps ◽  
Upper Level ◽  
Climate Scale ◽  
Climate Studies ◽  
Tornado Outbreaks ◽  
East West

AbstractThis study investigates relationships between climate-scale patterns and seasonal tornado outbreaks across the southeastern United States. Time series of several daily climate indices—including Arctic Oscillation (AO), North Atlantic Oscillation (NAO), Pacific–North American (PNA) pattern, east/west Pacific Oscillation (EPO/WPO), and both raw and detrended Gulf of Mexico SST anomalies (SSTA/SSTAD)—are collected in advance of Southeast severe convective days and grouped using self-organizing maps (SOMs). Spatiotemporal distributions of storm reports within nodes are compared to seasonal climatology, and the evolution of the regional environment for nodes associated with outbreaks is analyzed to provide physical justification for such associations. This study confirms findings from several tornado-related climate studies in the literature, while also identifying a number of new patterns associated with Southeast tornado outbreaks. Both the AO and NAO are relevant across all seasons, especially on lead time scales of 1–2 months, while SSTA/SSTADs are relevant on smaller time scales. The physical connection between these patterns and the regional storm environment is largely related to alterations of upper-level circulation and jet stream patterns, which in turn influence deep- and low-level shear, inland transport of moisture and instability, and other regional characteristics pertinent to tornado outbreaks. These results suggest that climate-scale variability can modulate and potentially be used to predict regional storm environments and their likelihood to produce tornado outbreaks across the Southeast.

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