Estimation of global scale aerosol distribution to evaluate its effect on global warming

为了评价人为排放源和自然排放源对气溶胶浓度的相对贡献，发展了气溶胶全球尺度化学输送模型AGCTM。该模型可以追踪形成气溶胶颗粒的各种化学物种的源-受体关系。2001年2月20日至3月31日期间，对气溶胶和其他化学物质的输送/化学/沉积进行了数值模拟。通过将计算结果主要与中国各观测点的TSP(总悬浮颗粒物)浓度以及日本东京和大阪的PM10进行比较，对模式的性能进行了评估。模式的性能可以概括为：首先，目前2.5×2.5度分辨率的全球模式在中国的许多地点如北京、上海、拉萨、西安、合肥、昆明、厦门等地产生了较好的和可接受的气溶胶浓度，但中国东北部的沈阳和哈尔滨等地除外。其次，在东京和大阪，计算与观测的一致性特别好，那里有100多个观测点，覆盖了2.5×2.5度的网格单元，这表明获取适当的数据进行比较具有重要意义。第三，该模型可能提供了硫酸盐、硝酸盐、有机碳、黑碳、土壤粉尘等各种气溶胶粒子的详细源-受体关系，这些粒子来自燃料燃烧、生物质燃烧、植被、火山、土壤等不同来源。为了改进模型，可能需要进一步调整土壤粉尘排放模型的参数，并适当地包括海洋气溶胶。

To evaluate relative contribution of both anthropogenic and natural emission sources to aerosol concentration, AGCTM (Aerosol Global scale Chemical Transport Model) has been developed. The model can trace source-receptor relations on various chemical species forming aerosol particles. Numerical simulations of transport/chemistry/deposition of aerosols and other chemical species were performed during 20 February to 31 March in 2001. Performance of the AGCTM has been evaluated by comparing the calculation results mainly with TSP (Total Suspended Particulates) concentration at various observation sites in China and with PM10 at Tokyo and Osaka in Japan.The model performance can be summarized as follows: first, the global model with current 2.5x2.5 degree resolution produced relatively good and acceptable aerosol concentrations at many locations in China such as Beijing, Shanghai, Lhasa, Xi'an, Hefei, Kunming, Xiamen, etc. except for those in northeastern China such as Shenyang, and Harubin. Second, agreement of calculation with observation is particularly good in Tokyo and Osaka, where more than 100 observation points were available to cover 2.5x2.5 degree grid cell, indicating importance to get appropriate data for comparison. Third, the model potentially provides detailed source-receptor relationship for various kinds of aerosol particles such as sulfate, nitrate, organic carbon, black carbon, soil dust, etc. originated from various source types such as fuel combustion, biomass burning, vegetation, volcano, soil, etc. For the model's improvement, further adjustment of parameters of soil dust emission model and appropriate inclusion of marine aerosols may be required.