郑州地区大气气溶胶光学特性的地基遥感研究

Ground-based measurements of aerosol optical properties in Zhengzhou, China

根据自动跟踪扫描光度计观测资料，利用Bouguer-Lamber定律反演郑州地区2007年2-9月气溶胶光学厚度和波长指数，分析郑州地区该时段气溶胶光学特性的季节变化和日变化情况.结果表明，郑州地区2007年2-9月1020nm气溶胶光学厚度为0.49±0.09；870nm气溶胶光学厚度为0.60±0.13；670nm气溶胶光学厚度为0.76±0.20；440nm气溶胶光学厚度为1.08±0.34.季节变化以夏季最高，秋冬次之，春季最低.波长指数春季为0.37-0.69，夏季为1.18-1.26.春季有50%以上的天气，扬尘粒子为主控粒子，而夏季城市-工业气溶胶是主控粒子之一.日变化规律与近地面污染物浓度变化一致，8：30和17：00左右出现峰值，11：30出现谷值，由于气温上升，湍流剧烈，12：30左右气溶胶光学厚度有1个小高峰，但仍处于全天的低值区.

A CE-318 automatic sun tracking spectrophotometer was used to measure direct solar radiation at Zhengzhou, China from February to September 2007. The aerosol optical depth （AOD）, wavelength exponent （α） were retrieved using Bouguer-Lamber law and their seasonal and diurnal variations were studied. During the study period, the value of AOD at Zhengzhou was 0.49±0.09, 0.60±0.13, 0.76±0.20 and 1.08±0.34 at 1020, 870, 670 and 440nm, respectively. The AOD varied seasonally, with a summer maximum, a winter and autumn second place and a spring minimum. The value of α ranged between 0.37-0.69 in spring and 1.18-1.26 in summer, which indicated that the dust was principal aerosol in half of time in spring and the industry-urban aerosol dominated in summer. The diurnal variability of AOD was consistent with the diurnal variability of surface air pollution, with a maximum at 8：30 and 17：00 and a minimum at 11：30. Another smaller peak value of AOD occurred at 12：30 with the raise of temperature, but which was also lower than the values of other time.