摘要
对2006年春季北京城区大气气溶胶中沙尘和黑碳气溶胶吸收系数的波长指数及其对总吸收系数的贡献进行了估算。结果表明:2006年春季北京城市地区测点,黑碳气溶胶吸收系数随波长的变化呈指数递减,假设某些天的气溶胶吸收无沙尘的贡献,估算的波长幂指数α=-0.92。另外,计算了北京3次浮尘天气下沙尘气溶胶对吸收系数(520nm波段)的贡献,计算表明,在浮尘天气影响期间,沙尘气溶胶对吸收系数的贡献平均为32.8%,黑碳气溶胶仍是浮尘影响期间城市气溶胶吸收消光的主要物质。
A statistic regression approach was introduced to estimate the wavelength index of black carbon and dust particles, and further to separate the contribution of the two types of aerosols to the aerosol light absorption coefficients measured in the spring of 2006 in Beijing urban area. The results show that the wavelength exponent index （α） of black carbon aerosol at Beijing urban site was about -0.92, which was in agreement to the value of （-0.8 ± 0.2） reported in related studies. The decoupling analysis of the measured light absorption coefficients during the three floating dust periods at Beijing in the spring of 2006 （March 25th, March 27th, April 9th） demonstrate that, on average, light absorption caused by dust particles takes up about 32.8% of total light absorption at 520 nm wavelength, and by black carbon aerosol more than 60%, which indicates that the black carbon is still the major contributor of aerosol light absorption in Beijing urban areas even in the floating dust periods.
出处
《气候变化研究进展》
CSCD
2007年第5期249-254,共6页
Climate Change Research
基金
国家自然科学基金项目(40675009)
国家自然科学基金重点项目(40433008)
国家社会公益性研究项目(2001D1A10009)资助
关键词
沙尘
黑碳
吸收系数分离
吸收系数波长指数
dust
black carbon
decoupling of aerosol absorption coefficient
wavelength exponent index
