西北四省吸收性气溶胶时空动态分布及其影响因素

利用OMAERUV数据日产品，对西北四省（陕西省、甘肃省、青海省和宁夏回族自治区）2005—2019年紫外吸收性气溶胶指数（Ultraviolet Aerosol Index，UVAI）数据进行提取及分析，探讨其时空变化特征及影响因素.结果表明：在时间变化上，西北四省UVAI值呈波动上升的变化趋势；季节方面，UVAI均值大小为：冬季>春季>秋季>夏季，四季变化规律基本同步；从空间上看，UVAI值呈由西北向东南逐步递减的空间分布，UVAI的高值区分布在格尔木市、酒泉市、张掖市及临近区域；UVAI值稳定性存在显著的空间差异，整体呈现东西两端集聚、中部分散、高低差异显著的分布格局.自然因素中，UVAI值与气温、降水均呈显著负相关，但受地形、风向的影响显著，西部与西北部气流是吸收性气溶胶输送的主要路径.人为因素中，不同产业间与UVAI存在显著的正相关性，另外，UVAI值与机动车保有量、工业废气排放量也呈显著正相关，表明机动车尾气排放量与工业废气排放量也对吸收性气溶胶具有重要贡献.通过后向轨迹追踪发现，该区域西北和西部气流是UVAI外来输送的最主要路径.

Spatiotemporal dynamic distribution and influencing factors of absorbable aerosols in four provinces of Northwest China

Based on OMAERUV data daily products, the ultraviolet aerosol index (UVAI) data of four provinces in Northwest China from 2005 to 2019 were extracted and analyzed, and the spatiotemporal variation characteristics and influencing factors were explored. The results showed that:in terms of time change, the UVAI values showed a fluctuating upward trend; in terms of seasons, the average value of UVAI was as follows:winter > spring > autumn > summer, and the variation rule of four seasons was basically synchronous; from the perspective of space, the spatial distribution of UVAI value gradually decreased from northwest to southeast, and the areas with high UVAI value included Golmud City, Jiuquan City, Zhangye City and adjacent areas. There are significant spatial differences in the stability of UVAI values, and the overall distribution pattern of agglomeration in the East and West, dispersion in the middle, and significant difference between high and low. Among the natural factors, UVAI value is significantly negatively correlated with temperature and precipitation, but it is significantly affected by topography and wind direction. The western and northwest airflow is the main routes for the transport of absorbent aerosols. Among the human factors, there is a significant positive correlation between UVAI and different industries. In addition, the UVAI value has an extremely significant positive correlation with the motor vehicle population and industrial exhaust emissions, indicateing that vehicle exhaust emissions and industrial exhaust emissions also have an important contribution to the absorption of aerosols. Through the backward trajectory tracking, it was found that the northwest and Western airflow was the main route for the external transport of UVAI value.