Research Lidar Detection Method Of Atmosph-Eric Pressure

The mass of the air column per unit area is called atmospheric pressure.In modern meteorological sciences,accurate barometric pressure data is the key to accurate weather analysis and forecasting.Atmospheric pressure is an extremely important physical parameter in meteorology.It is necessary to carry out high-precision remote sensing detection technology for atmospheric pressure profiles.In this thesis,the research of lidar detection technology for the atmospheric pressure profile of 40 km from the ground to the upper altitude is carried out.The atm ospheric detection area is divided into three layers according to the atmospheric conditions at different altitudes and the characteristics of lidar scattering signals,which are 0-12 km,10-25 km,and 25-40 km,respectively.Aiming at different height layers,methods of detecting atmospheric pressure using Rayleigh scattering atmospheric pressure,vibrating Raman signal to detect atmospheric pressure and vibration-rotating Raman are proposed respectively.In the high-altitude area above 20 km,the aerosol content is very small and can be basically ignored.The size of the Rayleigh signal reflects the change in molecular number density.The atmospheric pressure can be retrieved using the Rayleigh signal;in the range of 10-25km,a small amount of gas The presence of the sol will affect the Rayleigh signal,so the vibration Raman signal must be selected to retrieve the atmospheric pressure;in the range of 0-12 km,the aerosol concentration is very high,and the molecular number density is very sensitive to the aerosol,so the rotating Raman is used The signal first retrieves the atmospheric temperature and then deduces the atmospheric pressure.Using the lidar detection data of the Lidar Remote Sensing Center of Xi’an University of Technology,data inversion of atmospheric pressure was carried out,and compared with sounding data,an accuracy analysis was carried out.Inversion of 0-40 km atmospheric pressure data is realized.The main error of inversion of atmospheric pressure by rotating Raman signal comes from temperature deviation,reference point deviation and atmospheric specific humidity deviation,and the comparison deviation between the obtained atmospheric pressure profile and sounding data is less than 5 hPa;vibrational Raman The error of signal inversion atmospheric pressure mainly comes from reference point error and atmospheric transmittance error.The comparison deviation between inversion results and sounding data is less than 4 hPa;the error of Rayleigh signal inversion atmospheric pressure mainly comes from reference point deviation And the signal-to-noise ratio,the deviation between the inversion results and the sounding is less than 6 hPa.In this thesis,through the inversion and analysis of the measured data,the Lidar method of atmospheric pressure detection has been initially realized.The inversion data proves the feasibility of the proposed method.