The Study Of Characteristics Of Infrared Radiation Of Middle And Upper Atmosphere And Its Application Based On Model

In this dissertation,the infrared radiation properties of the middle and upper atmosphere are investigated by limb infrared model.The middle and upper atmospheric parameter' data set is analyzed to investigate the method to convert the parameter observations into the empirical model for limb infrared model.The limb infrared model of the middle and upper atmosphere is used to evaluate the availability of infrared detection of near-space target.The main content and results include:1.The limb radiation properties of the typical infrared bands under the quiescent condition are investigated by improved SHARC(Strategic High-Altitude Radiance Code)non-LTE(non-Local Thermodynamics Equilibrium)model.The limb radiances of different seasons and latitudes and different solar activities and geomagnetism activities are presented and analyzed.2.The limb radiation properties of the typical infrared bands under the auroral condition are investigated by comparison between SHARC auroral model simulation and quiescent model simulation.The differences are presented and analyzed.The radiance spectra and limb radiance time evolution are also presented and analyzed in detail.3.The LTE limb radiance model is developed using the molecular absorption algorithm of CART(Combined Atmospheric Radiative Transfer).The comparison between CART LTE model simulation and SHARC non-LTE model simulation shows that limb infrared radiation in the middle and upper atmosphere is not always affected by non-LTE significantly.In the stratosphere and lower mesosphere,non-LTE has negligible effect on the most infrared bands' limb radiance,which means that LTE model is effective in these regions.4.TIMED/SABER(Thermosphere Ionosphere Mesosphere Energetic and Dynamic/Sounding of the Atmosphere using Broadband Emission Radiometry)daytime CO2 VMR(Volume Mixing Ratio)data set is analyzed to investigate the method that can be used to abstract the empirical functions from the observations of atmospheric parameters that are critical to the limb infrared model(e.g.temperature,CO2 VMR,O3 VMR).The multiple linear regression fitting proves to be effective to build the empirical model of the middle and upper atmospheric parameters.This will help to improve the accuracy of the infrared model.5.The limb infrared contrast model of target and background is built to investigate the detection of near-space target.The contrast is simulated based on the limb infrared model because the middle and upper atmosphere limb radiation is the main background for the near-space target.The contrasts in the typical infrared bands are presented to analyze the availability of detection preliminarily.