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针对全球变暖贡献最大的两种温室气体CO2和CH4，采用自行研制的地基傅里叶变换近红外光谱遥测系统连续观测了合肥地区2012年2月到2013年4月的直射太阳光光谱，进而获得整层大气透过率测量光谱。在前向模型中采用逐线积分、低阶多项式近似方法得到整层大气透过率模拟光谱。利用模拟透过率光谱在CO2的6150～6270 cm -1波段、CH4的5970～6170 cm-1波段对测量透过率光谱进行迭代拟合，获得气体柱浓度。以O2柱浓度为内标函数获得CO2和CH4的干柱体积混合比。CO2和CH4干柱体积混合比日均值都具有较大波动性和明显的季节周期性，它们的月均值整体上具有较强的一致性，但是变化特征不尽相同。与日本温室气体卫星瓦里关地区的报道结果相比，C O 2含量峰谷值对应的时间相对滞后，并且峰值到谷值的转变时间较长；与利用SCIAMACHY 资料分析的全国范围内CH4柱浓度平均值变化趋势相比， C H4含量表现出夏高冬低的单峰单谷型变化趋势。它们的变化特征与源和汇的平衡、气象和气候条件等复杂因素有关，还需长期观测和深入研究。“,”In order to observe two kinds of greenhouse gases ,CO2 and CH4 ,making the biggest contribution to global warming , a ground-based Fourier transform near-infrared spectral remote sensing system was developed to record the perpendicular inci-dence sun spectra from February 2012 to April 2013 in Hefei continuously .The measured total transmittances in the atmosphere were obtained from perpendicular incidence sun spectra .Methods of line-by-line and low-order polynomial approximation were used to model the total atmospheric transmittances in forward model .The measured transmittance spectra were fitted iteratively using the modeled transmittance spectra in the regions of CO2 6 150~6 270 and CH4 5 970~6 170 cm -1 in order to obtain their column concentrations .The column-average dry-air mole fractions of CO2 and CH4 were obtained with the internal standard function of O2 column concentrations .CO2 and CH4 daily average values of column-average dry-air mole fractions changed with a larger fluctuation and obvious seasonal periodicity .Their monthly average values were consistent as a whole ,although there were different characteristics .Compared with the results reported by Japanese greenhouse-gas satellite in the area of Waliguan , there was a time lag corresponding to peak and trough of CO 2 content and the change from peak to trough costed a long time . CH4 content showed variation tendency of unique peak and trough ,higher in summer and lower in winter ,compared with aver-age values of nationwide CH4 column concentrations based on SCIAMACHY data .The variation characteristics were related to complex factors such as the balance of source and sink ,meteorological and climate conditions ,and required long-term observa-tion and further study .