中文摘要：

采用全球气溶胶模式（GOCART）模拟结果,讨论了东亚地区沙尘气溶胶时空分布、排放与沉降以及区域输送特征.结果表明,中国境内沙源主要位于塔克拉玛干沙漠、河西走廊及河套地区.排放强度春季最大,夏季和秋季逐渐减小,冬季最弱,且强度逐年减弱,区域年平均排放为581Tg/a.模拟的沙尘光学厚度（AOD）分布与卫星观测具有很好的一致性,其中塔克拉玛干沙漠AOD大值与沙尘暴活动密切相关,其出现时间最早,持续时间最长.区域平均而言,干沉降和湿沉降可以分别清除77%和22%的沙尘排放,其中沙尘源区干沉降起主导作用,远离源区的东北及西北太平洋,湿沉降更加重要.沙尘大粒子主要通过重力干沉降移出,而湿沉降对小粒子贡献超过60%.重力干沉降全年（特别是春季）起主导作用,对流降水湿沉降在夏季作用显著增强,总体来说,沙尘总沉降速率逐年减小.东亚沙尘气溶胶通过3条输送带自西向东传输,可以影响我国华北、华中和华南.对散度的研究表明,气溶胶平流项对沙尘源区气溶胶辐散作用较大,沙尘排放显著影响该地区沙尘的输送和AOD;而塔里木盆地西侧沙尘辐合中心是风场辐合辐散项导致的,说明地形和风场对该地区沙尘输送和AOD很重要.

英文摘要：

The spatial and temporal distribution, production and deposition, and regional transport of mineral dust aerosol over East Asiawere quantified by usingthe Goddard Chemistry Aerosol Radiation and Transport（GOCART） model. Model results showed thatthe Takalamakan Desert, the Hexi Corridor, and the Hetao Area were the main dust source regions in China. The dust production waslargest in spring, relatively small in summer and autumn, and reachedits minimum value in winter. Moreover, the dust production was gradually decreased year by year. The annual mean of regional dust emission waspredicted to be 581Tg/a. In general, the modeled dust aerosol optical depth（AOD） agreed well with the satellite observations spatially and temporally. Specifically, the high AOD in the Takalamakan Desert was notably influenced by the dust storm activities, in which AOD reached its peaks earlierin a year and kept longer compared with other sources. On the annual mean of regional basis, the dry and wet depositionscould remove 77% and 22% of the total dust production, respectively. The dry deposition was the dominate dust removal process over dust sources, while the wet deposition was more important when dust was transportedto northeastern China and the northwestern Pacific oceans. Furthermore, the removal process of coarse mode dust was mainly determined by gravitational dry deposition, in contrast, the wet deposition contributedto more than 60% of the removal process of accumulate mode dust. As the most important component, the gravitational dry deposition dominatedthe dust removal process throughout the year, especially in spring, while the wet deposition from convectiveprecipitationcould not be neglected in summer. Similar to dust production, the dust deposition also showed a decreasing trend over the simulation period. There were three major dust transport routes in East Asia, by which the dust aerosol could be transported from the dust source regions to northern, central, and southern China. In addition, the dust divergence regi