Defense Presentation

Jia Yue

Ph.D. Final
July 30, 2009, 10 am - 12 pm
Engineering B101

Abstract:  Using data from the CSU sodium Doppler lidar and Kyoto University OH airglow imager at Fort Collins, CO (40.6N, 105W), supplemented by meteorological data in the lower atmosphere, this thesis provides a comprehensive, though qualitative, understanding for three different yet related observed fluid-dynamical phenomena in the mesopause region. The first project involves the convection-excited gravity waves observed in the OH airglow layer at 87 km. Two case studies on May 11, 2004 and September 9, 2005 are discussed in detail along with statistical studies and a ray-tracing modeling. A single convection source matches the center of the concentric gravity waves. The horizontal wavelengths and periods of these gravity waves were measured as functions of both radius and time. These results agreed reasonably well with the internal Boussinesq gravity wave dispersion relation with an assumed zero background wind. The weak mean background wind between the lower and middle atmosphere (10 to 90 km) determines the penetration of the gravity waves into higher altitude. The second project involves mesospheric bores observed by the same OH imager. The observation on October 9, 2007 reveals the close correlation between breaking large-scale gravity waves and mesospheric bores. It suggests that when a large-amplitude gravity wave is trapped in a thermal or shear duct, its wave front could steepen and forms bore-like structure in the mesopause. In turn, the large gravity wave and its bore may significantly impact the background. Studying all ~8 observed cases reveals the possible link between the jet/front system in the lower atmosphere and the propagation and ducting of large-scale gravity waves and associated bores in the mesopause region of the atmosphere. The third project involves the relationship between large wind shear generation and sustainment and convective/dynamic stabilities measured by the sodium lidar at the altitude of 80-105 km during 2002-2005. A large wind shear could substantially affect the electrodynamics in the ionosphere through Lorentz force acting on ionized particles. The correlation between windshear, S, and Brunt-Vaisala frequency, N, as observed by lidar suggests that the maximum sustainable windshear is determined by the necessary condition for dynamic instability of Richardson number R=0.25, leading to the result that the maximal windshear occurs at altitudes of lower thermosphere where the atmosphere is convectively very stable (large value of N2), ~ 100 km in winter and ~ 90 km in summer. Through a case study and more than 20 examples (not shown), we conclude that at the temporal and vertical resolution of 15 min and 2 km, the dominate source for sustainable large windshears appears to be the semidiurnal tidal-period perturbations with shorter vertical wavelengths and greater amplitude, compared to the typical solar tides. Though the observations of concentric gravity waves, mesospheric bores and large windshears were made previously at other locations, our long-time studies with 5 to 10 times more observational data have enabled us to draw new comprehensive conclusions.

Adviser: Chiao-Yao (Joe) She
Co-adviser: Steven C. Reising
Non-ECE member: David A. Krueger (physics)
Member3: Steven Reising
Member4: Mario C. Marconi
Additional member: NA

Publications:
[9] Yue J., C.-Y. She, T. Nakamura, S. Harrell and T. Yuan (2009), Mesospheric bore formation from long wave perturbations observed by collocated all-sky OH imager and sodium lidar, J. Atmos. Sol. Terr. Phys., under review.
[8] Yuan T., J. Yue, C.-Y. She, J. Sherman, M. White, S. Harrell, P. Acott, D. A. Krueger (2009), A novel wind-bias correction scheme for narrowband sodium Doppler lidars using Iodine absorption spectroscopy, Applied Optics, 48(20),3988–3993.
[7] Huang, W., X. Chu, J. Wiig, B. Tan, C. Yamashita, T. Yuan, J. Yue, S. D. Harrell, C.-Y. She, B. P. Williams, J. S. Friedman, and R. M. Hardesty (2009), First Field demonstration of simultaneous wind and temperature measurements from 5 to 50 km with a Na double-edge magneto-optic filter in a multi-frequency Doppler LIDAR, Optics Letters, 34(10), 1552-1554.
[6] Yue J., C.-Y. She, B. Williams, J. Vance, P. Acott and T. D. Kawahara (2009), Continuous-wave sodium D2 resonance radiation generated in single-pass sum-frequency generation with Periodically Poled Lithium Niobate, Optics Letters, 34, 1093-1095.
[5] Yue J., S. Vadas , C.-Y. She , T. Nakamura , S. Reising ,H.-L. Liu , P. Stamus, D. Krueger, W. Lyons, T. Li (2009), Concentric gravity waves in the mesosphere generated by deep convective plumes in the lower atmosphere near Fort Collins, Colorado, J. Geophys. Res., 114, D06104, doi:10.1029/2008JD011244.
[4] Vadas S., J. Yue, C.-Y. She, P. Stamus and A. Z. Liu (2009), A model study of the effects of winds on concentric rings of gravity waves from a convective plume near Fort Collins on 11 May 2004, J. Geophys. Res., doi:10.1029/2008JD010753.
[3] Li T., C. -Y. She, H.-L. Liu, J. Yue, T. Nakamura, D. A. Krueger, Q. Wu, X. Dou, and S. Wang (2009), Observation of local tidal variability and instability, along with dissipation of diurnal 2 tidal harmonics in the mesopause region over Fort Collins, CO (41N, 105W), J. Geophys. Res., doi:10.1029/2008JD011089.
[2] She, C.-Y., J. Yue, Z.-A. Yan, J. W. Hair, J.-J. Guo, S.-H. Wu, and Z.-S. Liu, (2007), Direct-detection Doppler wind measurements with a Cabanne-Mie lidar: A. Comparison between iodine vapor filter and Fabry-Perot interferometer methods, Appl. Optics, Vol. 46, Issue 20, pp. 4434-4443.
[1] She, C.-Y., J. Yue, Z.-A. Yan, J. W. Hair, J.-J. Guo, S.-H. Wu, and Z.-S. Liu, (2007), Direct-detection Doppler wind measurements with a Cabanne-Mie lidar: B. Impacts of aerosol variation on iodine vapor filter methods,


Program of Study:
AT601-001, Atmospheric Dynamics I
AT602-001, Atmospheric Dynamics II
EE404-001, Experiments-Optical Electroncs
EE441-001, Optical Electronics
EE550A-001, Microprocessors Based Systems
PH521-001, Introduction to Lasers
PH522-L02, Introductory Laser Laboratory
PH572-001, Math Methods for Physics II
PH 692-001, Seminar
EE 695 V-002, Independent Study
EE 795 V-002, Independent Study
EE 799 V, Dissertation
PH 795 V-001, Independent study