Dissertation > Excellent graduate degree dissertation topics show

Study of the Lidar Techniques for Remote Sensing of the Atmospheric Temperature and Aerosol Profiles

Author: LiuJun
Tutor: HuaDengZuo;LiYan
School: Xi'an University of Technology
Course: Mechanical Engineering
Keywords: Rotational Raman lidar Temperature Aerosol High-spectral-resolution lidar Boundary layer
CLC: TN958.98
Type: PhD thesis
Year: 2008
Downloads: 961
Quote: 4
Read: Download Dissertation


Atmospheric boundary layer, which is closest to the surface of the earth, influences the activity of human being. The human activities in day-to-day directly affect the state of the atmospheric boundary layer. Therefore the study of atmospheric boundary layer is though of very importance for the solar radiation and heat transfer geodynamics, explanation of global warming phenomenon, improvement of local weather forecast accuracy, prevention and treatment of air pollution, especially for urban meteorological change. Atmospheric lidar, as an active remote sensing tool, has been proved to be powerful in atmospheric measurement, with a large detection range, high spatial resolution, continuous monitoring with high accuracy and real-time. It has been widely used in the research fields of laser atmospheric transmission, global climate prediction, radiation effect of the atmospheric aerosol and environment monitoring.This thesis mainly focuses on the fine detection of atmospheric temperature profiles in the boundary layer and the aerosol profiles in the troposphere. Methods and key techniques of rotational Raman scattering lidar with high-accuracy detection of lower atmospheric temperature during daytime are studied. Characteristics of Xi’an urban aerosol spatial variations are also observed and analyzed with Mie scattering lidar. A kind of high-spectral-resolution lidar for accurate profiling of atmospheric aerosol optical properties is proposed.In order to eliminate the strong solar background during daytime and high-density aerosol influence on the temperature detection in the lower atmosphere, a new spectroscopic filter is proposed for the UV temperature lidar system based on rotational Raman scattering. With the help of combination of high-spectral-resolution grating and an edge-mirror, the major portion backgrounds yielded from the solar and Mie and Rayleigh scattering are blocked. To achieve a high noise suppression rate, narrow-band interference filter is used to reject the remaining Mie-Rayleigh scattering signal in each Raman scattering channel. Theoretical analysis and experimental results show that the lidar system and the detection methods can suppress system noise effectively. And the accurate profiling of the lower atmospheric temperature during daytime can be achieved. The temperature error less than 1K is obtained up to 2.3 km for nighttime and 1.8 km for daytime measurement with 250 mJ laser pulse energy and 4 minutes observation time.For the needs of urban aerosol profiling in Xi’an and sand storms forecasting, the research of the aerosol observation experiment by Mie lidar and corresponding data procession of aerosol optical properties has been developed. The aerosol distribution data in Xi’an was given firstly. For real-time observing three-dimensional profiles of aerosol, a small portable scanning lidar system was designed to detect the optical properties of atmospheric aerosols and cirrus, horizontal visibility and so on.For fine detection of atmospheric aerosol profiles, an UV high-spectral-resolution lidar system was proposed and established on the basis of analyzing the existing technique of aerosol detection and data inversion. The system uses a high-spectral resolution grating to split solar background spatially to meet the requirement of daytime detection. Since the system uses a Fabry-Perot etalon to split out the Doppler broadened Rayleigh scattering signal, the concentration of aerosols have no influence for the detection results. By use of the diffraction effect of the grating, the system may detect the water vapor profiles simultaneously.

Related Dissertations

  1. Preparation and Electrocaloric Effect of BaxSr1-xTiO3 Ferroelectric Thin Films,TB383.2
  2. Measurement of the Surface Impedance of the High Temperature Superconducting Thin Films with Coplanar Transmission Line,O484.5
  3. Numerical Investigation of Effects of Boundary Layer Suction on the Performance of Diffusion Cascade,TH453
  4. Study on Contact Fatigue Life Based on Grease Variation with Temperature,TH117.22
  5. Research on Temperature Measurement Technique Based on CCD Image Sensor,TH811
  6. Development of Explosion Flame Temperature Measurement System Based on Multi-Spectral Thermometry,TH811
  7. Temperature Drift Modeling and Compensation of Fiber-Optic Gyroscopes,V241.5
  8. Simulation Analysis on Temperature Stress of RCC Arch Dam and Its Construction Joints Design Research,TV642.2
  9. Analysis and Study of Abutment Stability in Concrete High Arch Dam by Three-Dimensional Nonlinear Finite Element Method,TV642.4
  10. Research on Nozzle Plume Temperature Distribution Measurement System,V434
  11. Numerical Analysis of Flow Process in a Molten Carbonate Fuel Cell,TM911.4
  12. Experimental Research on Concretion Characteristics of High Temperature Syngas in Integrated Gasification Combined Cycle System,TM611.3
  13. The Basic Research of Axial Flux Inductor Type High Temperature Superconducting Motor,TM37
  14. Research on Temprature Controling Technology of Laser Diode with Thermoelectric Cooler,TN248.4
  15. Research on Millimeter Wave Imaging with Scanning Array,TP391.41
  16. The Development of Electric Control System for Product Line of Cross-Linked Cable,TP273.5
  17. Research on Temperature Control System for Laser Diode,TP273
  18. Design and Study of Temperature Chamber Control System in Servo Table,TP273
  19. Research on Temperature Control System for High-Performance Oven-Control Crystal Oscillator (OCXO),TN752
  20. Fly Ash study of low temperature ceramic foam,TU52
  21. Photosynthetic Apparatus Response to Heat Stress and the Mechanisms in Two Different Cotton with Various Leaf Colours,Q945.11

CLC: > Industrial Technology > Radio electronics, telecommunications technology > Radar > Radar: institutional sub- > Optical positioning radar,laser radar
© 2012 www.DissertationTopic.Net  Mobile