Sulfur Distribution and Transport Studies in East Asia Using Eulerian Model

A three-dimensional regional Eulenan model of sulfur deposition and transport is developed.Processes treated in the model include emission,transport,diffusion,gas-phase and aqueous-phase chemical process,dry deposition,ramout and washout of sulfur.A 'looking up table' method is provided to deal with the gas-phase chemical process including sulfur transfer Dry-depositon velocity considers the influence of underlying surface,wind,degree of stability by parameterization Model calculated values reasonably agrees with observation.Distribution of sulfur deposition and transport in East Asia are also analyzed in this paper Some amount of sulfur emission of different countries transport across boundaries,but the main origin of sulfur deposition in each country in East Asia is from itself.Furthermore.some transport paths on different layers and outlet or inlet zones are found.According to sulfur balance and budget we concluded that sulfur outlets are bigger than inlets across boundary and emissions are more than deposition in most places of East Asia

我国和东亚地区硫化物跨边界输送态势研究

本文利用污染物三维欧拉长距离输送实用模式，较详细地模拟了我国和东亚地区硫化物跨地区、跨边界输送态势，分析了东亚地区硫化物输送通量随高度、季节变化的分布特点，讨论了不同地区边界上硫化物的跨边界输送通量及流的收支平衡，并给出了我国和周边国家和地区之间硫化物的相互输送量。结果表明，我国向外输送的硫化物占周边国家和地区总硫沉降的比例并不大，各地区硫沉降的主要来源是自身排放；硫化物长距离输送中硫酸根的输送占重要地位，各地区硫酸根沉降中的外来比例较大。我们初步总结出一个东亚地区硫化物输送的概念模式：在低层，夏季主要自西南向东北输送，冬季长江以北自北向南输送，长江以南由西南向北输送，并在长江中下游地区形成一个较强的硫化物辐合带，在高层，无论冬夏均由西向东输送，并随高空带变化，中层为二者的过渡，春秋季的情形界于冬夏之间，偏向冬季。

未来东亚地区硫化物沉降及输送的预测

采用东亚未来二氧化硫排放量的预测资料，利用东亚硫化物输送模式拟了未来１５年东亚各地区的硫化物沉降量、相互输送量的变化趋势力其对土壤的影响。结果表明，未来１５年东亚各地区的硫化物沉降量将日益增多，一些地区硫化物沉降量大大超出了土壤对酸沉降的承受能力，对周边地区硫化物的输送量也将进一步加大，形势相当严峻。