京津冀区域沙尘暴和群发性强沙尘暴特征分析

利用京津冀区域内102个气象站1954～2002年观测资料,分析了此区域沙尘暴和群发性强沙尘暴的变化特征.结果表明:京津冀区域绝大部分地区是沙尘暴主要影响区,冀北高原是此区域的易发区和多发区.沙尘暴发生时间具有明显的日变化特征和季节差异,沙尘暴呈现整体减少趋势,各分区变化趋势具有相似性,只是在减少幅度上略有不同.近50年此区域共出现了39例群发性强沙尘暴,冀北高原和定州、饶阳一带是此区域群发性强沙尘暴天气的多发区.多发季节为春季(3～5月),占全年总数的76.9%,尤以4月份最多,占全年总数的51.3%.群发性强沙尘暴年代际变化呈现总体减少趋势,其发生次数、覆盖面积均以90年代为最低值.

Analysis of Dust-storms and Severe Group Dust-storms in Beijing-Tianjin-and-Hebei Region

Based on the available observation data from 102 meteorological stations in Beijing-Tianjin-and-Hebei region from 1954 to 2002, the changing characteristics of dust-storms and severe group dust-storms in this area are analyzed. The results show that the most parts of this region are affected by dust-storms. The plateau in the north of Hebei province is prone to dust-strom. The time of dust-storm occurrence varies with day and season. In general, the frequency of dust-storms decreases in this region. The trends of dust-storm change are similar in different areas of this region, but the rate of decrease is slightly different. In recent 50 years, 39 severe group dust-storms occurred in Beijing-Tianjin-and-Hebei region. The plateau in the north of Hebei and the Dingzhou-and-Raoyang region are prone to severe group dust-storms. The dust-storm season is from March to May.76.9% of severe group dust-storms occur in this period. 51.3% of group dust-storms take place April. The inter-decade change of severe group dust-storms decreases in this region. The numbers of severe group dust-storms and affected area are the smallest in the 1990s.