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A QUANTITATIVE ANALYSIS of the DUST DEVIL Peter C. Sinclair A

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A QUANTITATIVE ANALYSIS of the DUST DEVIL Peter C. Sinclair A A quantitative analysis of the dust devil Item Type text; Dissertation-Reproduction (electronic) Authors Sinclair, Peter Charles, 1929- Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 11/10/2021 03:42:14 Link to Item http://hdl.handle.net/10150/565138 A QUANTITATIVE ANALYSIS OF THE DUST DEVIL Peter C.vX Sinclair A Dissertation Submitted to the Faculty of the DEPARTMENT OF METEOROLOGY In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY In the Graduate College THE UNIVERSITY OF ARIZONA 19 6 6 STATEMENT BY AUTHOR This dissertation has been submitted in partial fulfillment of requirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this dissertation are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or re­ production of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his judgment the proposed use of the material is in the in­ terests of scholarship. In all other instances, however, permission must be obtained from the author. 22. r SIGNED: ACKNOWLEDGMENTS I wish to thank Dr. Dean 0. Staley for his helpful dis­ cussions and advice during the course of this study. 1 also express my appreciation to Dr. A. R.. Kassander for his support and many helpful suggestions especially during the instrument and field measure­ ment phases of the program. The aid of Don MacArthur and Dave MacArthur with the instrumentation and field measurements, and Richard MacArthur and John Edwards with the data reduction is gratefully acknowledged. Also, the preparation of the illustrations by Don Perceny is greatly appreciated. The Office of Naval Research is acknowledged for their support through Contract Nonr 2173(03). iii TABLE OF CONTENTS Page LIST OF FIGURES.................... vii LIST OF T A B L E S ............................................... xiv ABSTRACT ..................................................... xv CHAPTER I. INTRODUCTION..................................... .. 1 II. GENERAL CHARACTERISTICS OF DUST DEVILS ................. 10 Spatial Distribution .................... ..... 13 Diurnal Variation ................................ 20 Thermal Properties of the Atmosphere and Dust Devil Occurrence .............................. 28 Effect of Environmental Wind on Dust Devil Occurrence ......................................... 33 Duration " ............ ........................... 36 Environmental Wind and IXist Devil Movement ..... 40 Direction of Rotation ............................... 42 III. INSTRUMENTATION AND FIELD O P E R A T I O N S .................. 30 Mobile Recording System (MRSl) .................... 50 Instrumentation ............................... 50 Measurements ................................... 56 Mobile Meteorological Tower (MRS2) ................ 61 Wind Velocity Instrumentation .................. 61 Pressure Instrumentation .............. ..... 68 Temperature Instrumentation ..................... 79 Recorder . •..................................... 81 Mobile Tower and Field Operations .............. 81 Air-Borne Recording System (ARS) ................... 87 Choice of Airplane as Research Vehicle .......... 87 Vertical Velocity Instrumentation .............. 91 Temperature Instrumentation .................. 92 Recording System ....... .............. 95 Method of Operation ............................. 96 iv TABLE OF CONTENTS— Continued Page IV. THE LOWER STRUCTURE OF DUST DEVI L S.................... 99 Temperature, Pressure, and Wind Velocity Profiles . 99 Characteristic Profile Features .................. 103 Temperature ..................................... 103 P r e s s u r e ......................................... 106 Wind Velocity ................................... 109 The Model 124 The Interaction of Just Particles and Ai r ......... 128 Theory of Multiphase Flow ....................... 128 Particle Distribution ..... .............. 143 Heating of the Air by IXist ....................... 149 V. THE UPPER STRUCTURE OF DUST DEVILS ......................153 Vertical Velocity and Temperature Profiles ..... 159 Composite M o d e l ............ 165 VI. THE GOVERNING EQUATIONS OF M O T I O N ..................... 174 Coordinate S y s t e m ................................ 174 Derivation of Equations of Turbulent Com­ pressible F l o w ................................... 176 Simplifying A s s u m p t i o n s .......... 182 Quasi-Steady State ....................... 182 Penetration Assumption ......................... 184 Axial S y m m e t r y ................................... 185 Incompressibility ............................... 189 Effect of the Earth's Rotation ............. 190 Density V a r i a t i o n s .......... 191 Viscosity Coefficients ......................... 191 Reduced E q u a t i o n s .....................* .......... 194 VII. ORDER OF MAGNITUDE ANALYSIS OF TERMS IN EQUATIONS OF MOTION 195 Data Smoothing Procedure ........................... 195 Computational Procedure ........ .......... 196 Magnitude of Terms in Equations of Mo t i o n ............201 Simplified Equations ........................... • 226 vi TABLE OF CONTENTS— Continued Page VIII. COMPARISON OF THE MEASURED VERTICAL VELOCITY AND THAT COMPUTED BY THE ADIABATIC M E T H O D .................. 230 Adiabatic Method .................. ....... 230 Derivation of Governing Equation .................. 230 Distribution of Vertical Motion from Quali­ tative Considerations ............................... 236 Verification of the Adiabatic M e t h o d .................238 Errors of the Adiabatic Method .................... 241 IX. DISCUSSION AND CONCLUSIONS ............................. 257 Comparison of Dust Devil Measurements With Theo­ retical Vortex Models and Other Natural or Artificial Vortices .................................. 257 Rankine-Cyclostrophic Vortex ..... ............ 257 Gutman's Theoretical Vortex .................... 265 Donaldson-Sullivan Theoretical Vortex ........... 270 Further Research ................................... 273 APPENDIX 1 279 2 ................................................... .. 282 3 284 REFERENCES ...................................................... 285 LIST OF FIGURES FIGURE Page 1.1 A Typical Desert Dust Devil ...................... 2 2.1 Dust Devil Census Areas ......................... 11 2.2 Spatial Distribution of Dust Devils Observed in the Tucson Census Area Airing 8 June - 20 June 1962 . 14 2.3 Spatial Distribution of IXist Devils Observed in the Avra Valley Census Area During 22 June - 27 July 1962 ..................................... 2.4 Diurnal Variation of Dust Devil Occurrence for the Tucson Basin ................................. 2.5 Diurnal Variation of Dust Devil Occurrence for the Avra Valley ................................. 2.6 Diurnal Variation of Dust Devils of Various Sizes for the Avra Valley ........ .............. 27 2.7a Relationship Between Maximum Surface Temperature at Ryan Field and Maximum Surface Temperature at Tucson Airport during 18 June - 28 July 1962 . 2.7b Relationship Between Average Cloud Cover and Average Number of Dust Devils Observed per Day for the Avra Valley and the Tucson Basin.......... 2.8a,b Relationship of Maximum Surface Temperature and Average Number of Dust Devils Observed per Day for the Avra Valley and the Tucson Basin . 2.8c,d Relationship of Surface to 850 mb Lapse Rate and Average Number of Dust Devils Observed per Day for the Avra Valley (c) and the Tucson Basin (d) . 31 2.9a,b Relationship of 850 mb Lapse Rate and Average Number of Dust Devils Observed per Day for the Avra Valley (a) and the Tucson Basin (b) . 2.9c,d Relationship of 700-500 mb Lapse Rate and Average Number of Dust Devils Observed per Day for the Avra Valley (c) and the Tucson Basin (d) . vii viit LIST OF FIGURES--Continued FIGURE Page 2.10a,c Relationship Between Average Wind Speed and Average Number of Dust Devils Observed per Hour of a Specified Wind Speed R a n g e .............. 34 2.10b,d Relationship Between Resultant Wind Direction and Average Number of Dust Devils Observed per Hour of a Specified Wind Direction Range . 34 2.11 Relation Between Frequency of Dust Devil Occurrence and Dust Devil Duration for the Avra V a l l e y ....................................... 37 2.12 Relation Between Frequency of Dust Devil Occurrence and Dust Devil tXiration for the Tucson Basin ..................................... 38 2.13a,b Frequency of Dust Devils Moving From Different Directions for the Avra Valley (a) and the Tucson Basin ( b ) ................................. .. 41 2.13c,d Relation of Dust Devil Direction of Motion and the Environmental Surface Wind Direction for the Avra Valley (c) and the Tucson Basin (d) . 41 3.1 Mobile Recording System (MRS1) ..................... 52 3.2a,b Interior View of (a) MRSl Photo Box and (b) Pressure Instrument ............ ,............. 53 3.3 Temperature, Pressure, and Horizontal Wind Velocity Measurements Through Two IXist Devils: (a) July 19, 1960, 1305 MST: (b) July 14,1960, 1330
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