中国西部本底大气中CO的连续测量

在中国西北部的瓦里关全球基准站(36°17'N,100°54'E,3810m asl)建立了气相色谱-汞置换法大气CO连续测量系统.组装调试和运行标定表明,色谱方法的基线稳定,分离度高,检测方法可靠,系统具有高自动化的操作性能和严格的质量控制,其设计完全符合世界气象组织(WMO)全球大气本底测量的要求.根据采样现场大气CO浓度的变化,采用经国际比对的CO标准气系列,用峰高外标法设定可调整的标准工作曲线计算环境CO浓度,系统对CO的检测限低至1×10^-9(V/V),检测精度小于0.1%,准确度在±0.05%以内,可提供我国本底地区近地层大气CO连续而精确的现场测量结果.

Continuous Measurement of Baseline Atmospheric Carbon Monoxide in Western China

In-situ custom-designed gas chromatography(GC)-HgO system was established for the continuous measurement of atmospheric CO at Waliguan Baseline Station(36°17'N,100°54'E,3816m asl) in western China. The system's assembling, testing, running and calibration indicated that the chromatographic method has stable baseline and high separation efficiency, as well as reliable detection method. This system adopted high automatic operating techniques and followed strict quality control. It is up to the standard of WMO's baseline watch on global atmosphere. According to the flask sampling results of in-situ CO variation at Waliguan, CO standards in clean dry air under international comparison were used to determine the adjustable working standard curves, so as to calculate the ambient CO mixing ratios based on peak height. This system's detection limit for CO is around 1×10^-9(V/V),the precision is below 0.1% and accuracy in ±0.05%, it can provide continuous and accurate surface CO mixing ratios in baseline areas of China.