I would first like to thank my wife of 8 years, Nikisha. She is one of the major reasons that I c... more I would first like to thank my wife of 8 years, Nikisha. She is one of the major reasons that I chose to pursue my Ph.D. and has been a constant source of love and support in the entire time I have known her. You are my life, thank You for everything. I also want to send my love to our 2 year old daughter Nora. I would like to thank Dr. Alan Liu for providing the guidance throughout the dissertation work and writing. Your ideas and suggestions were invaluable to my effort of this entire project. Many thanks to you for allowing me to be with my family while completing this degree. To my committee members Dr. Hickey, Dr. Snively and Dr. Swenson, thank you for lending your time and expertise in reviewing this body of work. Thanks go to my Mother, Carole Rogers and my Father, Samuel Agner Jr. for your unconditional love and support throughout my entire life and for instilling in me your values, morals and ethics that guide me. Thanks also go to my older sister, Amanda and my younger sister, Sarah. We have all been through good times and bad times and have emerged from them with stronger bonds than before. To my mother-in-law and sister-in-law I would like to express my gratitude for everything you have given both of us, from coming all the way from India to help take care of Nora while I finished this degree and for your love. Thanks are given to my entire family for everything you have given me throughout my life. 2.1 Zonal wind (m/s) for the first 10 days of March 2006 at 100 • longitude, 30 • latitude and 95km altitude from eCMAM (top) and SD-WACCM (bottom). 2.2 Zonal wind (m/s) at 95km altitude and -25 • latitude for the first ten days of March 2006 from eCMAM (top) and SD-WACCM (bottom). . . . . . . . . . 2.3 Symmetric (a,b) and antisymmetric (c,d) Hough modes for DW1 computed using associated Legendre polynomial expansions. The labels represent the value of n (Wang et al., 2016
Atmospheric dynamics comprise of a multitude of phenomena from various sources that affect the en... more Atmospheric dynamics comprise of a multitude of phenomena from various sources that affect the entire climate of the globe. Some of these phenomena include Atmospheric Gravity Waves which are ubiquitous features around the planet. They are important mechanisms for the transport of momentum and energy from the lower atmosphere to the upper atmosphere. The sun is the ultimate source of energy for the earth and the primary driver of atmospheric dynamics. The 11-year solar cycle of the sun has had a noticeable effect on the overall climate of the earth in the past. More recent work has seen the diurnal tides being directly influenced by the change in solar energy over the solar cycle at the South Pole. The different types of atmospheric waves interact with each other in complex manners that are still a subject of research today. Gravity waves are known to be modulated by solar tides and vice versa so a change in the tides will induce a change in gravity waves. The solar cycle influence on tides can then be seen overall in gravity wave wavelengths and speeds. A CCD Spectrometer is used to gather temperatures and brightness's of two separate airglow layers in the upper atmosphere at 87km (OH) and 93km (O 2 ). Two different years are chosen to be analyzed for solar cycle dependencies. One year is 2002, during the previous time of maximum solar activity and the other is 2010, just after the last minimum of solar activity. Time series of temperatures and brightness's are analyzed for gravity Without this opportunity I would not be where I am today. Thanks go to my Mother, Carole Rogers and my Father, Samuel Agner Jr. for your unconditional love and support throughout my entire life and for instilling in me your values, morals and ethics that guide me. Thanks also go to my older sister, Amanda and my younger sister, Sarah. We have all been through good times and bad times and have emerged from them with stronger bonds than before. To my mother-in-law and sister-in-law I would like to express my gratitude for everything you have given both of us, from coming all the way from India for our wedding and for your love from half-way across the world. Thanks are given to my entire family for everything you have given me throughout my life.
Journal of Atmospheric and Solar-Terrestrial Physics, Dec 1, 2015
Gravity waves and atmospheric tides have strong interactions in the mesopause region and are majo... more Gravity waves and atmospheric tides have strong interactions in the mesopause region and are major contributors to the large variabilities in this region. How these two large perturbations interact with each other is not well understood. Wind and temperature measurements from a Na LIDAR at the Starfire Optical Range (35.0 N, 106.5 W), New Mexico from 24 nights between 1998 and 2000 are used to derive local time variations of gravity wave momentum flux and corresponding local time tidal variation of the background wind. The diurnal component of the momentum flux shows a clear modulation by the tide. The gravity wave forcing on the diurnal tidal amplitudes is shown to have an altitudinal and directional dependence.
Atmospheric dynamics comprise of a multitude of phenomena from various sources that affect the en... more Atmospheric dynamics comprise of a multitude of phenomena from various sources that affect the entire climate of the globe. Some of these phenomena include Atmospheric Gravity Waves which are ubiquitous features around the planet. They are important mechanisms for the transport of momentum and energy from the lower atmosphere to the upper atmosphere. The sun is the ultimate source of energy for the earth and the primary driver of atmospheric dynamics. The 11-year solar cycle of the sun has had a noticeable effect on the overall climate of the earth in the past. More recent work has seen the diurnal tides being directly influenced by the change in solar energy over the solar cycle at the South Pole. The different types of atmospheric waves interact with each other in complex manners that are still a subject of research today. Gravity waves are known to be modulated by solar tides and vice versa so a change in the tides will induce a change in gravity waves. The solar cycle influence on tides can then be seen overall in gravity wave wavelengths and speeds. A CCD Spectrometer is used to gather temperatures and brightness's of two separate airglow layers in the upper atmosphere at 87km (OH) and 93km (O 2 ). Two different years are chosen to be analyzed for solar cycle dependencies. One year is 2002, during the previous time of maximum solar activity and the other is 2010, just after the last minimum of solar activity. Time series of temperatures and brightness's are analyzed for gravity Without this opportunity I would not be where I am today. Thanks go to my Mother, Carole Rogers and my Father, Samuel Agner Jr. for your unconditional love and support throughout my entire life and for instilling in me your values, morals and ethics that guide me. Thanks also go to my older sister, Amanda and my younger sister, Sarah. We have all been through good times and bad times and have emerged from them with stronger bonds than before. To my mother-in-law and sister-in-law I would like to express my gratitude for everything you have given both of us, from coming all the way from India for our wedding and for your love from half-way across the world. Thanks are given to my entire family for everything you have given me throughout my life.
Gravity waves and thermal tides are two of the most important dynamical features of the atmospher... more Gravity waves and thermal tides are two of the most important dynamical features of the atmosphere. They are both generated in the lower atmosphere and propagate upward transporting energy and momentum to the upper atmosphere. This dissertation focuses on the interaction of these waves in the Mesosphere and Lower Thermosphere (MLT) region of the atmosphere using both observational data and Global Circulation Model (GCMs). The first part of this work focuses on observations of gravity wave interactions with the tides using both LIDAR data at the Star Fire Optical Range (SOR, 35◦N, 106.5◦W) and a meteor radar data at the Andes LIDAR Observatory (ALO, 30.3◦S, 70.7◦W). At SOR, the gravity waves are shown to enhance or damp the amplitude of the diurnal variations dependent on altitude while the phase is always delayed. The results compare well with previous mechanistic model results and with the Japanese Atmospheric General circulation model for Upper Atmosphere Research (JAGUAR) high re...
Journal of Atmospheric and Solar-Terrestrial Physics, 2015
Gravity waves and atmospheric tides have strong interactions in the mesopause region and are majo... more Gravity waves and atmospheric tides have strong interactions in the mesopause region and are major contributors to the large variabilities in this region. How these two large perturbations interact with each other is not well understood. Wind and temperature measurements from a Na LIDAR at the Starfire Optical Range (35.0 N, 106.5 W), New Mexico from 24 nights between 1998 and 2000 are used to derive local time variations of gravity wave momentum flux and corresponding local time tidal variation of the background wind. The diurnal component of the momentum flux shows a clear modulation by the tide. The gravity wave forcing on the diurnal tidal amplitudes is shown to have an altitudinal and directional dependence.
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