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Heavner M 2000.Pdf Optical spectroscopic observations of sprites, blue jets, and elves: Inferred microphysical processes and their macrophysical implications Item Type Thesis Authors Heavner, Matthew James Download date 05/10/2021 11:09:22 Link to Item http://hdl.handle.net/11122/9529 INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6” x 9” black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. Bell & Howell Information and Learning 300 North Zeeb Road, Ann Arbor, Ml 48106-1346 USA 800-521-0600 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. OPTICAL SPECTROSCOPIC OBSERVATIONS OF SPRITES, BLUE JETS, AND ELVES: INFERRED MICROPHYSICAL PROCESSES AND THEIR MACROPHYSICAL IMPLICATIONS A THESIS Presented to the Faculty of the University of Alaska Fairbanks in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY By Matthew James Heavner. B.S.. B.A. Fairbanks, Alaska May 2000 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number 9965378 ____ UMI UMI Microform9965378 Copyright 2000 by Bell & Howell Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. Bell & Howell Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, Ml 48106-1346 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. OPTICAL SPECTROSCOPIC OBSERVATIONS OF SPRITES, BLUE JETS, AND ELVES: INFERRED MICROPHYSICAL PROCESSES AND THEIR MACROPHYSICAL IMPLICATIONS By Matthew James Heavner RECOMMENDED: APPROVED: Dean, College of Science. Engineering and Mathematics DeapMjf the Graduate School Date Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Abstract During the past decade, several new upper atmospheric phenomena associated with thun­ derstorms have been discovered. The four main types of optical emissions are now called sprites, blue jets, elves, and halos. Sprites are primarily red and appear between 40-95 km altitude and last between 1-100 ms. The dominant sprite emission is the molecular nitrogen first positive band, a relatively low energy emission also observed in the red lower borders of aurorae. The total optical energy output of a bright sprite is on the order of 50 kJ. Based on spectral observations, the total vibrational and electronic energy deposited in molecular nitrogen and oxygen in the upper atmosphere is 250 MJ-l GJ. Blue jets hist hundreds of milliseconds and span altitudes 15-40 km. Spectral observations of blue jets have not been obtained to date. Elves, the third type of observed optical emissions above thunderstorms, are red emissions at altitudes 75-95 km, lasting one millisecond or less. Elves and halos are similar phenomena, but are distinct based on altitude and duration. Halos typically last 3-6 ms and occur at lower altitudes than elves. This dissertation describes the optical spectrum of sprites obtained by the University of Alaska Fairbanks during summ er campaigns of 1995. 1996. and 1998. and its implication to the understanding of the electrodynamics of the middle atmosphere. The single most sign- ficant result is the determination that a typical sprite deposits up to one gigajoule into the mesosphere. These forms of electrical energy coupling from tropospheric thunderstorms into the stratosphere, mesosphere, and thermosphere/ionosphere may have critical implications for the global chemistry and energy budgets in these regions. iii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Contents List of Figures ........................................................................................................................ vi List of Tables ............................................................................................................................ viii Preface ........................................... ix Acknowledgements ................................................................................................................. x 1 Introduction 1 2 First Decade of Sprite Observations 9 2.1 Anecdotal Reports and Initial Documentation ...................................................... 10 2.2 1994-Physical Dimensions. ELF/VLF. Blue Jets ................................................ 17 2.2.1 Blue Jets and Blue Starters ........................................................................... 19 2.2.2 Palm Tree ............................................................................................................ 23 2.3 1995-Equatorial Sprites. Optical Spectroscopy. E lv es ......................................... 26 2.3.1 Equatorial Sprites ............................................................................................ 26 2.3.2 Optical Spectroscopy ......................................................................................... 27 2.3.3 Elves and "Sprite Halos" ............................................................................... 30 2.4 1996-High Spatial Resolution. NIR Spectra, and Blue Sprites ........................ 32 2.5 1997-High Speed Imagery. Australian Sprites. Blue Sprites ............................ 34 2.6 1998-Blue Spectra. NUV Sprites. High Spatial Resolution. Japanese Sprites 35 2.7 1999-NASA Sprites Balloon. High Speed Im agery ................................................ 44 2.8 Sum m ary of O b se rv atio n s ........................................................................................... 45 2.9 Theories of Sprite and Jet Production .................................................................... 47 iv Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. V 3 Spectral Observations 52 3.1 Spectral Observations (550-1000 nm ) ...................................................................... 54 3.2 Optical Atmospheric Emissions ................................................................................ 57 3.2.1 Molecular Nitrogen First Positive Emissions ............................................ 62 3.2.2 Molecular Nitrogen Second Positive Emissions ...................................... 63 3.2.3 Ionized Molecular Nitrogen Meinel Em issions ......................................... 64 3.2.4 Ionized Molecular Nitrogen First Negative Emissions ............................ 64 3.2.5 Atmospheric Transm ission .............................................................................. 65 3.3 Comparison of Sprite. Auroral. Lightning, and St. Elmo's Fire Spectra . 67 3.4 Variability of Observed Spectra ................................................................................ 71 3.5 Spectral Observations (340-460 nm) ...................................................................... 75 3.6 Spectral Observations of H alos ................................................................................ 77 3.7 Conclusions and Suggestions for Future Observations ........................................ 78 4 Spectrographic Analysis 79 4.1 Red Spectral A n a ly s is ................................................................................................ 80 4.1.1 O b s e rv a tio n s ..................................................................................................... 80 4.1.2 Theory ............................................................................................................... 85 4.2 Interpretation of near-UV/Blue Observations ..................................................... 87 4.3 Spectral Implications for Energetics of Sprites ..................................................... 93 4.4 Global Energy Deposition .......................................................................................... 96 4.5 Chemical Effects .......................................................................................................... 96 4.6 C o n clu sio n s ..................................................................................................................... 98 5 Summary and Conclusions 99 Appendix A Recent Anecdotal Reports of Sprites 105 Appendix B Instrumentation 113 Bibliography 123 Reproduced with permission
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