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准确测量CO2在大气中的垂直分布对于验证卫星和地基光谱仪及估计CO2源、汇至关重要.本文描述了一种原位大气采样系统(aircore).我们利用这套系统在内蒙古锡林浩特地区于2018年6月13日和14日获取了CO2和CO廓线并与对流层监测仪(TROPOMI),轨道碳观测(OCO-2)和哥白尼大气监测服务(CAMS)比较.TROPOMI监测的CO柱总浓度(XCO)与原位测量CO廓线计算的XCO一致,平均偏差为5±1.89 ppb.OCO-2监测的CO2柱总浓度与原位测量廓线所得结果一致,平均偏差为.0.4±0.6ppm.6月13日,OCO-2后验廓线与原位测量廓线有明显偏差,OCO-2低估了250 hPa和600 hPa高度间的CO2浓度,高估了600 hPa高度以下的CO2浓度.CAMS的CO廓线与原位测量廓线在6月13日的偏差与OCO-2相似,但是在6月14日偏差较小.因为6月13日,一个弱的低压环流经过锡林浩特地区并于6月14日消失.在平流层,它们的偏差都很显著.柱总浓度的一致性和垂直分布的明显偏差说明这套廓线产品具有进一步的科学应用价值.“,”Accurate measurements of the vertical distribution of carbon dioxide (CO2) in the atmosphere are critical to validate the vertical columns recorded by satellite and ground-based spectrometers and to estimate sources and sinks of CO2.This work describes an in-situ air-sampler system (Aircore).Profiles of CO2 and carbon monoxide (CO) were retrieved from two soundings of this system in Xilin Hot on 13 and 14 June 2018,and compared with observations from the Tropospheric Monitoring Instrument (TROPOMI),Orbiting Carbon Observatory-2 (OCO-2),and Copernicus Atmosphere Monitoring Service (CAMS).The column-averaged mixing ratio of CO (XCO) monitored by TROPOMI agreed well with that calculated from the in-situ CO profile,with a small mean difference of 5 ± 1.89 ppb.The column-averaged mixing ratio of CO2 (XCO2) monitored by OCO-2 also agreed well with that calculated from the in-situ CO2 profile,with a slight bias of 0.4 ± 0.6 ppm.The OCO-2 a posteriori profile had an obvious bias compared with the in-situ CO2 profile on 13 June,with an underestimation between 600 hPa and 250 hPa and an overestimation below 600 hPa.CAMS also had the same bias compared with the in-situ CO profile;however,CAMS agreed well with the in-situ CO profile on 14 June in the troposphere because a weak cold vortex passed Xilin Hot on 13 June and disappeared on 14 June.In the stratosphere,there were significant biases in the vertical degradation.The striking agreement between the column-averaged mixing ratios and the differences in the vertical distribution suggests new exciting applications for the profile product.