利用地基高分辨率傅里叶变换红外光谱技术探测大气氟氯烃气体CCl_(2)F_(2)的时空变化特征  

Detection of atmosphere CCl_(2)F_(2) spatio-temporal variations by ground-based high resolution Fourier transform infrared spectroscopy

作　　者：曾祥昱 王薇[1] 刘诚 单昌功 谢宇 胡启后 孙友文 Polyakov Alexander Viktorovich Zeng Xiang-Yu;Wang Wei;Liu Cheng;Shan Chang-Gong;Xie Yu;Hu Qi-Hou;Sun You-Wen;Polyakov Alexander Viktorovich(Key Laboratory of Environmental Optics and Technology,Anhui Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Hefei 230031,China;Department of Precision Machinery and Instrumentation,University of Science and Technology of China,Hefei 230026,China;Department of Automation,Hefei University,Hefei 230601,China;Faculty of Physics,Saint Petersburg State University,Saint Petersburg 199034,Russia)

机构地区：[1]中国科学院合肥物质科学研究院安徽光学精密机械研究所,环境光学与技术重点实验室,合肥230031 [2]中国科学技术大学精密机械与精密仪器系,合肥230026 [3]合肥学院自动化系,合肥230601 [4]Faculty of Physics,Saint Petersburg State University,Saint Petersburg 199034

出　　处：《物理学报》2021年第20期3-11,共9页Acta Physica Sinica

基　　金：国家重点研发计划(批准号:2019YFC0214702,2018YFC0213201);国家自然科学基金(批准号:41775025)资助的课题.

摘　　要：大气二氯二氟甲烷(CCl_(2)F_(2),CFC-12)是人工合成的化学制剂,对平流层臭氧可产生严重的破坏和损耗.研究大气CFC-12的探测技术并获取其时空分布和变化,对了解区域氟氯烃气体变化趋势以及对平流层臭氧的影响具有重要意义.本文利用地基高分辨率傅里叶变换红外光谱(Fourier transform infrared spectroscopy,FTIR)技术研究大气CFC-12的垂直分布和柱浓度的反演方法,基于最优估计算法反演2017-2020年合肥地区大气CFC-12的垂直廓线和柱总量.合肥大气CFC-12反演获得的垂直廓线表明,大气CFC-12在对流层以及低平流层处具有较高浓度,在垂直高度40 km以上浓度极低.合肥地区大气CFC-12的柱浓度含量呈现出夏季浓度较高,冬季与初春浓度较低的季节变化;观测期间大气CFC-12柱浓度呈现缓慢下降的趋势,年均变化率为-0.68%.将地基观测数据与ACE-FTS卫星观测数据进行比对,在高度范围16-28 km内两个CFC-12偏柱总量的相关性系数为0.73,可见地基和卫星数据具有较好的一致性.长期观测结果表明了地基高分辨率FTIR技术在观测大气中CFC-12的浓度垂直分布与季节变化上具有高的准确性和可靠性.Atmospheric dichlorodifluoromethane(CCl_(2)F_(2),CFC-12),as a synthetic chemical agent,is a main stratospheric ozone-depleting substance in atmosphere.Studies of the detection techniques and the temporal and spatial distribution of CFC-12 have great significance in understanding the variation trend of regional CFCs and their influence on stratospheric ozone.In this study,the method of retrieving the vertical profile and total column for CFC-12 is studied based on ground-based high-resolution Fourier transform infrared spectroscopy(FTIR).The spectral window for CFC-12 retrieval is selected as 922.5–923.6 cm–1,where the interfering gases are H_(2)O,O_(3),and CO_(2).The result of error analysis shows that the average total error is 1.27%,including the systematic error 0.76%and random error 1.02%.The vertical profiles and total columns of atmospheric CFC-12 in Hefei during the period from 2017 to 2020 were retrieved based on the optimal estimation algorithm.The vertical profiles of CFC-12 show that the concentration of atmospheric CFC-12 is high in the troposphere and low stratosphere at the altitude of 0–20 km,and then decreases,very low at height above 40 km.The total column average kernel of retrieved CFC-12 profiles is higher at 15–20 km,and the typical signal degree of freedom of CFC-12 is 1.217.Moreover,the long-term total columns of atmosphere CFC-12 observed show obvious seasonal variation in Hefei.Total columns of atmosphere CFC-12 are higher in summer and lower in winter and early spring.The maximum monthly concentration of CFC-12 is about 1.13×10^(16) mol·cm^(-2) in July,and the minimum monthly concentration is 1.00×10^(16) mol·cm^(-2) in March.Also,the annual average total columns of atmospheric CFC-12 decreased slightly from 2017 to 2020,with an increasing rate of–0.68%.This reflects the effect of China's implementation of CFCs control ban policy.Furthermore,in order to verify the accuracy of ground-based FTIR observation,we compare our ground-based observation data with ACE-FTS/SCISAT sate

关 键 词：二氯二氟甲烷 太阳吸收光谱 柱总量 垂直廓线 

分 类 号：O657.33[理学—分析化学] X831[理学—化学]