依据黄河中上游地区19个城市2007年SO2源排放总量和气象资料，利用MM5、CALPUFF数值模式系统，数值模拟分析了城市间的相互影响以及长距离输送对北京SO2浓度的贡献。结果表明，黄河中上游城市间SO2污染物排放相互影响较大的有银川、石嘴山、中卫、吴忠和渭南、铜川、咸阳、宝鸡两个城市群。周围城市对银川年平均浓度的贡献占到二级标准的50%，对咸阳年平均浓度的贡献占到二级标准的44%。对周边城市SO2年平均浓度贡献超过二级标准10%的城市有：石嘴山对银川，吴忠对银川，渭南对咸阳、铜川，咸阳对渭南。长距离输送对北京有一定影响，其中年平均浓度贡献最大的是鄂尔多斯市0.00038mg/m3，包头市0.00032mg/m3次之，宝鸡市、延安市、银川市、中卫市、铜川市最小，为0.00001 mg/m3；SO2最大日平均浓度贡献最大的是鄂尔多斯市0.00540mg/m3，忻州市0.00414mg/m3次之，延安市0.00008mg/m3最小；SO2最大小时平均浓度贡献最大的是忻州市0.03708mg/m3，鄂尔多斯市0.01815mg/m3次之，中卫市0.00029mg/m3最小。因此，为提高空气质量，单一城市的污染控制规划和措施除考虑其对本地的影响外，还应充分考虑限定其对外界的贡献。
Based on the SO2 emission inventory and meteorological data along the middle-up stream of Yellow River in 2007, the simulation system including CALPUFF and MM5 models is utilized to simulate, predict and analyze the interaction of SO2 emission between one city and other 18 cities, and the contribution of their transport to Beijing city. From the results, the following conclusions can be reached. (1) It is obvious that the SO2 emission dramatically interacts with that around the circumjacent cities, in the second level (0.06mg/m3) of National Standard of SO2 emission, 49.8% and 44.3% of average yearly SO2 concentration in Yinchuan and Xianyang cities are contributed by that around the circumjacent cities, respectively. (2) The city whose contribution to neighboring city exceeds 10% of the second level includes Shizuishan to Yinchuan, Wuzhong to Yinchuan, Weinan to Xiangyang, Weinan to Tongchuan, and Xiangyang to Weinan. (3) The long distance transport of SO2 emission from adjacent cities influences to some extent the concentration of SO2 in Beijing city, the contribution of average yearly SO2 concentration to Beijing reaches 0.00038mg/m3 with the largest in Ordos,followed by Baotou, 0.00032mg/m3, and is only 0.00001mg/m3, the smallest for Baoji and Xinzhou and Yanan and Zhongwei and Tongchuan; the contribution of the maximum daily SO2 concentration to Beijing is Ordos with an extreme value of 0.005404mg/m3, followed by Xinzhou, 0.00414mg/m3, and is the minimum for Yanan, 0.00008mg/m3; the contribution of the maximum hourly SO2 concentration to Beijing is Xinzhou with an extreme value of 0.03708mg/m3, followed by Ordos, 0.01815mg/m3, and is the minimum for Zhongwei, 0.00029mg/m3. (4) For the purpose of improving the air quality, it is critical that its contribution to the surrounding regions should be circumscribed in addition to the consideration of its local influence in the pollution control and countermeasure of a single city.
