摘要
本文以搭载在风云三号D星上的红外高光谱探测仪(High-Spectral Infrared Atmospheric Sounder,简称HIRAS)为例,评估了通用快速辐射传输模式RTTOV(版本12)中臭氧含量空间和季节变化对模拟的红外高光谱探测仪亮度温度的影响.分析2019—2020年AIRS反演的全球臭氧浓度分布发现:臭氧主要集中在平流层1~50 hPa的高度,有明显的纬度带分布和季节变化;赤道地区臭氧浓度高,两极地区臭氧浓度低,变化范围约8 mg/m^(3).同一地点臭氧浓度有较明显的季节变化,变化幅度在±3 mg/m^(3)之间.用RTTOV模拟的HIRAS亮度温度对臭氧浓度变化的强敏感区主要在中心波长9.8μm的臭氧强吸收带波段,引起的亮温差可以达到几K的量级,其余通道(尤其是窗区)对臭氧浓度变化不敏感.RTTOV中给出的臭氧浓度缺省值在中低纬度地区偏低,而在极区赋值则偏高,使得模拟的HIRAS臭氧吸收通道亮温值在极区偏高、赤道地区偏低.贴近真实分布的臭氧浓度反演值模拟的9.8μm的亮温比用缺省值模拟的亮温更接近观测值,观测O与模拟B差(O-B)的平均值在0 K附近,概率密度函数分布从偏度和峰度参数的角度都更符合正态分布,而臭氧浓度用缺省值模拟的亮温有明显的正偏差.建立了全球逐月臭氧浓度廓线数据库,垂直101层、水平分辨率1°×1°,提供给资料同化时作为臭氧廓线的输入.
The influence of ozone concentration spatial and seasonal variation on brightness temperature simulated by community fast radiative transfer model RTTOV(version 12)is evaluated by taking HIRAS(high-spectral infrared atmospheric sounder)uploaded on China Fengyun polar orbiting meteorological satellite as an example in this paper.The distribution of global ozone content is analyzed by inversion of AIRS(Atmospheric Infrared Sounder)observation from 2019 to 2020.Ozone is mainly concentrated in the stratosphere 1~50 hPa with obvious latitudinal distribution and seasonal variation.The ozone concentration is high in the equatorial region and low in the polar region,with a variation range of about 8 mg/m^(3).At the same time,the ozone concentration in the same place has obvious seasonal variation within±3 mg/m^(3).The strong sensitivity of HIRAS brightness temperature to ozone concentration simulated by RTTOV is mainly in the strong ozone absorption band with the central wavelength of 9.8μm,and the brightness temperature difference can reach several K,while it is almost insensitive in other channels(especially the window band).The default value of ozone concentration given in the RTTOV model is lower in the middle and low latitudes,but higher in the polar region,which makes the simulated HIRAS brightness temperature in ozone absorption channels higher in the polar region and lower in the equatorial region.The 9.8μm brightness temperature simulated by the retrieved ozone concentration which is more consistent with the real ozone distribution is closer to the observed value than that simulated by the default value and the average bias(difference between observed and simulated brightness temperature)is around 0 K.The skewness and kurtosis parameters of bias probability density function distribution are more consistent with standard normal distribution,while the brightness temperature simulated by default value of ozone concentration has obvious positive deviation.
作者
官莉
刘薇
GUAN Li;LIU Wei(Key Laboratory of Meteorological Disaster(NUIST),Ministry of Education,Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters,Nanjing University of Information Science and Technology,Nanjing 210044,China)
出处
《地球物理学进展》
CSCD
北大核心
2022年第5期1818-1824,共7页
Progress in Geophysics
基金
国家自然科学基金项目(41975028)资助。
关键词
红外高光谱探测
辐射传输模式RTTOV
臭氧
High-Spectral Infrared Atmospheric Sounder
Radiative transfer model RTTOV
Ozone concentration profile
