浑善达克沙地对北京春季沙尘天气的贡献

The contribution of Hunshan Dake sandland during dusty days in Beijing April 2000

2000年4月我国北方干旱少雨,冷空气活动频繁,多次沙尘暴过程造成北京地区严重的沙尘天气.本文利用中尺度沙尘传输模式,模拟了4月3~14日期间的沙尘天气过程,并分析了浑善达克沙地对北京沙尘天气期间近地面沙尘质量浓度的贡献.结果显示,近地面沙尘中来自浑善达克沙地的最多占到20.9%,而境外源、北京周边局地源及华北荒漠化土地等其它沙尘源亦有相当重要的贡献.

Hunshan Dake sandland have been one of important sources of dust storm and dust aerosol in the Northern China since 1998 because of successive drought,frequent clod eddy and serious anthropogenic over-grazing action.In this paper,we employed the regional dust cycle model to simulate dust storms occurring in the Northern China from Apr.3 to Apr.14 in 2000.We also estimated the contribution of dust particles long-distance transported from Hunshan Dake sandland to dust mass concentration in lowest model atmospheric level in Beijing during dusty days in April 2000.The results showed that the dust particles longdistance transported from Hunshan Dake sandland accounted for less than 20.9% of dust mass concentration near the surface in Beijing during dusty days.The total contributions to dust concentration near the surface in Beijing during dusty days from other sources such as deserts in Mongolia,local regressive soil and desertification farmland soil in north China were greater than Hunshan Dake sandland.