| Atmospheric temperature,humidity are the main parameters forweather forecasting.The atmospheric parameter information retrived by using infrared high-resolution spectra is of great significance for quantitative assessment of optical wave propagation in the atmospherein optical engineering and improvement of weather prediction ability.The troposphere is the densest part of the Earth's atmosphere,and almost all essentially weather phenomena occur in the troposphere.Airborne infrared spectra provide a unique platform for meteorological observations in the troposphere and low stratosphere.This paper focuses on the the inverstigation of the retrival of atmospheric parameter based on airborne high-resolution infrared spectra.Main results are as follows:1.Simulations of atmospheric infrared radiation observations of ground-based AERI,airborne HIS and spaceborne AIRS were performed based on three commonly used radiatvie transfer models:LBLRTM,MODTRAN and CART.From the comparison of the simulations,we can know that LBLRTM performs better than MODTRAN and CART on the spectra simulation for ultra-high resolution infrared detection instruments AERI and HIS.And for the high-resolution infrared detection instrument AIRS,the simulation accuracy of LBLRTM,MODTRAN,and CART is equivalent.2.Both finite difference method and analytical method were used on the airborne platform HIS instrument to calculate the Jacobian of atmospheric temperature and humidity.The results show that the analytical method performan well on calculating the Jacobian.Besides,it can save lots of time and has practical applications in the inversions of atmospheric parameters from infrared spectra.3.Based on the theory of information entropy,bayesian estimation method is used to calculate the information capacity and degree of freedom of temperature and water vapor contained in the HIS observation system.The information capacity of temperature and water vapor are 49.5,bits and 25.2 respectively.And the degrees of freedom included are 10.5 and 5.6 respectively.The vertical resolution of the HIS inversion temperature and humidity profile is obtained based on the effective density method.The average vertical resolution of the retrieved atmospheric temperature is 2.2 km,and the vertical resolution of the water vapor is 2 km.Sensitivity analysis of HIS spectra was carried out,and the minimum accuand racy of HIS detection was analyzed according to the obtained temperature the sensitive wavelength band range for the seven main atmospheric absorption molecule gases.The accuracy of is 0.42K for temperature,and 7.9%for water vapor,respectively.4.The distribution iterative method is used to the selection the channel for atmospheric temperature profile inversion.And the influence of the number of used channels on the inversion results is analyzed.The atmospheric temperature profile can be inverted accurately enough with using of the 45 channels,there exists a redundancy with more channels.It can lead to not only the complexity of computation,but also the reduction of the inversion accuracy if there were more channels used.5.The atmospheric temperature profiles,surface temperatue and precipitable water vapor were successfully retrieved from airborn HIS data.The inversions of surface temperature and precipitable water vapor was carried out by the least squares method.The optimal estimation method and the Tikhonov regularization method are used to retrieve the temperature profiles of the Barrow and Sheba stations on the flight path.When the more accurate background profile and background error covariance are available,the results obtained by the optimal estimation method is most close to the true state of the atmosphere.If there are few background information of the observation area,the L curve method can be used to balance the observation value and the prior information on inversion.In this way,the inversion results are mainly influenced by observations,then the good results of retrieved atmospheric profile can still be obtained. |
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