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In-Situ Measurements of Temperature Fluctuation and Vertical Wind Shear for Altitudes up to 30 Km in the Atmosphere

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In-Situ Measurements of Temperature Fluctuation and Vertical Wind Shear for Altitudes up to 30 Km in the Atmosphere University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Masters Theses Graduate School 5-2018 In-Situ Measurements of Temperature Fluctuation and Vertical Wind Shear for Altitudes up to 30 km in the Atmosphere Younes Baalla University of Tennessee, [email protected] Follow this and additional works at: https://trace.tennessee.edu/utk_gradthes Recommended Citation Baalla, Younes, "In-Situ Measurements of Temperature Fluctuation and Vertical Wind Shear for Altitudes up to 30 km in the Atmosphere. " Master's Thesis, University of Tennessee, 2018. https://trace.tennessee.edu/utk_gradthes/5026 This Thesis is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Masters Theses by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a thesis written by Younes Baalla entitled "In-Situ Measurements of Temperature Fluctuation and Vertical Wind Shear for Altitudes up to 30 km in the Atmosphere." I have examined the final electronic copy of this thesis for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Master of Science, with a major in Engineering Science. Steven Brooks, Major Professor We have read this thesis and recommend its acceptance: James L. Simonton, Uwe Peter Solies Accepted for the Council: Dixie L. Thompson Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) In-Situ Measurements of Temperature Fluctuation and Vertical Wind Shear for Altitudes up to 30 km in the Atmosphere A Thesis Presented for the Master of Science Degree The University of Tennessee, Knoxville Younes Baalla May 2018 Copyright © 2018 by Younes Baalla. All rights reserved. ii Abstract An atmospheric profiling system has been developed at the University of Tennessee Space Institute. The system consists of temperature, pressure, humidity, relative wind, and a Global Positioning System GPS to track the payload’s position. A data logger unit was integrated into the instrument for saving measured atmospheric properties. The atmospheric profiling system was carried through the troposphere and up to the middle region of the stratosphere layer using high altitude balloons. The balloon is assumed to follow a Lagrangian path where the relative horizontal wind represents turbulent perturbations (i.e. gusts). The Parcel theory (a numerical model) used in meteorology to predict atmospheric instability and the Richardson number schemes used for turbulence were adopted in investigating the presence of turbulence indicators. Theories and terminologies relevant for the analysis of turbulence are described and the results from both methods were analyzed and compared. iii Table of Contents Chapter 1: Introduction .……………………………………………………………………………………………………..........1 1.1 Overview...................................………………………………………………………………………………............1 1.2 Background and Broader Impact...…………………………………………………………………………............1 1.3 Intellectual Merit ……………………………………………………………………………………………………...........2 Chapter 2: Program Description........................................................................................................4 2.1 Atmospheric Thermal Structure ……………………………………………………………………………........….4 2.2 Stratosphere Layer Characteristics …………………………………………………………………….......……...6 2.3 Sounding Data Analysis …………………………………………………………………………………….......………..7 2.4 Skew-T Log P Diagram …………………………………………………………………………………….......………....9 2.5 Atmospheric Stability ……………………………………………………………………………………........………....9 2.6 Stability indices …………………………………………………………………………………………………….....…...10 Chapter 3: Data Analysis Methods .................................................................................................11 3.1 Convective Available Potential Energy and Convective Inhibition Energy …......................11 3.2 Theoretical description of Turbulent Flows ……………………………………………………......………..12 3.3 Atmospheric Profiling System …………………………………………………………………………….............14 3.4 Sounding Instrumentations ………………………………………………………………………………........……14 3.5 System Integration and Performance………………………………………………………………….......……15 3.6 Sounding System Components…………………………………………………………………………........…….15 Chapter 4: Flight Test Methods.......................................................................................................16 4.1 Flight Test Method and Results ……………………………………………………………………….......……....16 4.2 Atmospheric Profile ………………………………………………………………………………………......………...17 4.3 Mean and Turbulent Wind Gust……………………………………………………………………......………....20 Chapter 5: Results and Conclusions............................................................................................... 22 5.1 Richardson Number ………………………………………………………………………………………….....…….…22 5.2 Stability Classification Scheme ………………………………………………………………………......………..23 5.3 Bulk Richardson Number …………………………………………………………………………………......……...26 5.4 Air Parcel Theory..................................................................................................................28 5.5 Conclusions ……………………………………………………………………………………………………….............31 References......................................................................................................................................33 Vita..................................................................................................................................................35 iv List of Tables Table 1: Pasquill Stability Class Correlation with Richardson Number............................................23 Table 2: Mauritsen and Svensson Stability Class Correlation with Richardson Number.................25 Table 3: Stability Category Classifications for Convective Available Potential Energy....................29 Table 4: Stability Category Classifications for Convective Inhibition Energy...................................30 v List of Figures Figure 1: Sketch of the observed and theoretical models.................................................................3 Figure 2: U.S. Standard Atmospheric Profile......................................................................................4 Figure 3: U.S. Air Force Example of Lifting Air Parcel on a Skew T log P chart..................................8 Figure 4: HAB Trajectory for Westwood Flight Test.........................................................................16 Figure 5: HAB Trajectory for Robert E. Lee Flight Test.....................................................................17 Figure 6: Atmospheric Profile versus time.......................................................................................18 Figure 7: In-Situ and Standard Atmospheric Temperature Profiles................................................18 Figure 8: Atmospheric Profile versus time.......................................................................................19 Figure 9: In-Situ and Standard Atmospheric Temperature Profiles.................................................19 Figure 10: Mean and wind speeds versus Altitude from Westwood HAB Experiment...................20 Figure 11: Wind Gust and wind speed from Westwood HAB Experiment......................................20 Figure 12: Mean and wind speeds versus Altitude from R. E. Lee HAB Experiment.......................21 Figure 13: Wind Gust and wind speed from R. E. Lee HAB Experiment..........................................21 Figure 14: Pasquill Classifications of Robert E. Lee Flight Test........................................................24 Figure 15: Pasquill Classifications of Westwood Flight Test............................................................25 Figure 16: Mauritsen Classifications of Robert E. Lee HAB.............................................................26 Figure 17: Bulk Richardson Number of Westwood Flight Test.......................................................27 Figure 18: Bulk Richardson Number of Robert E. Lee Flight Test...................................................28 Figure 19: Skew-T Log P Diagram of Westwood HAB Flight Test....................................................30 Figure 20: Skew-T Log P Diagram of Robert E. Lee HAB Flight Test................................................31 vi Chapter 1: Introduction 1.1 Overview The highest-flying research aircraft is the U-2 derived NASA ER-2 with a ceiling of 70,000 feet (21.3 km). In-situ measurements above this altitude are restricted to balloon and sounding rockets. As a result, information on turbulence scales above ~21km is sparse. Here we are measuring the in-situ turbulence from the surface to 105,000 feet (32 km) primarily utilizing wind velocity and meteorological measurements on a balloon payload. Turbulence is assumed to exist solely in the turbosphere (surface to 80km), above the turbosphere is assumed to be purely laminar flow with mixing by diffusion only. Our main atmospheric layers of interest are the troposphere, jet stream, tropopause and lower stratosphere. The troposphere is defined as the lowest region (surface to 11km) where temperature decreases with height. Colder air directly over warmer air is unstable at the smallest vertical scale. At the larger scale, this local instability is bounded by the adiabatic heating of the air parcels with compression, and the adiabatic
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