中国北部一次沙尘过程中沙尘气溶胶的时空分布及输送特性

The Spatio-temporal Distribution and Transport Behavior of a Dust Event in North China

利用CALIPSO（Cloud-Aerosol Lidar Infrared Pathfinder Satellite Observations）卫星观测资料,结合气溶胶模式模拟,分析了2011年4月28—30日发生的强度较大的一次沙尘远距离输送过程中气溶胶的时空分布特征及输送特性。结果表明,此次沙尘过程有两个源区,分别为中国南疆盆地和蒙古国中南部,并在沙尘输送过程中交汇于内蒙古西南部和甘肃地区;源区一（南疆盆地）沙尘主要分布高度在1km以下,退偏振比平均在0.35左右,色比值平均在0.6左右,且沙尘在输送过程中被抬升到自由对流层,并先后影响内蒙古西南部、甘肃、宁夏等地区,输送到内蒙古、甘肃地区时沙尘主要分布在2.5~3km高度,退偏振比主要分布在0.3~0.5,色比值主要分布在0.5~0.9。源区二（蒙古国中南部）沙尘先后影响内蒙古中西部地区、甘肃、山西北部、内蒙古中东部地区、河北北部、北京天津和东北地区西部部分地区,沙尘输送到中国内蒙古东部、北京、河北等地区时主要分布在1~4km高度,退偏振比值主要集中在0.3~0.5,色比值主要在0.7~1.2。

The spatio-temporal evolution and long-distance transport behavior of a heavy dust storm during A- pril 28-30, 2011 were analyzed using a combination of the CALIPSO （Cloud-Aerosol Lidar Infrared Path- finder Satellite Observations） Satellite measurements, a back-trajectory, as well as an aerosol model. The results showed that the dust event has two different source regions, south Xinjiang Basin and central and southern regions of Mongolia, respectively. The dust originated from these two regions met in the south- west of Inner Mongolia and Gansu during their transportation. The dust in south Xinjiang Basin was mainly located below 1 km with the averaged linear volume depolarization ratio of 0.35 and color ratio of 0.6, re- spectively. It mainly affected the southwestern of Inner Mongolia, Gansu and Ningxia. The dust particles were mainly located between 2.5 and 3 km high with linear volume depolarization ratio from 0.3 to 0.5 and color ratio from 0.5 to 0.9 when dust particles were transported to the Inner Mongolia and Gansu. The cen- tral and western region of Inner Mongolia, Gansu, northern Shanxi, central and eastern areas of Inner Mon- golia, northern Hebei, Beijing, Tianjin and the western part of the northeast China were successively influ- enced by the dust originated from the central and southern Mongolia and the dust particles are mainly located in 1-4 km high, with linear volume depolarization ratio and color ratio concentrated on 0.3-0. 5 and 0.7- 1.2, respectively, in the east of Inner Mongolia, Beijing and Hebei.