近14a也门降水异常的气候特征

Analysis of Climate Feature of Precipitation Anomalies in Yemen during 1990 2003

摘要:

利用1990-2003年也门7个测站降水资料,在分析近14 a也门降水季节变化特征的基础上,着重分析了也门夏季降水的年际变化特征。结果表明,也门降水异常的季节变化明显,异常在4-9月最大,尤其是7-9月,异常峰值所在月呈现出较明显的提早趋势;近14 a也门夏季降水呈现出增加的趋势,90年代末该趋势加大;近14 a也门夏季降水存在3 a和7 a左右的显著振荡周期。

Abstract:

Using the mean monthly precipitation data of recent 14 years at 7 stations in Yemen,seasonal variations of precipitation are studied.On the basis of the analysis on seasonal features of precipitation,interannual variations of summer rain fall are emphatically investigated.Results show that precipitation in Yemen has obviously seasonal changes with large positive anomalies in summer(April to September),especially in July,August,and September,and that the anomalies peak month moves up.In the last 14 years,summer precipitation takes on an increasing dency,which is more obvious in recent years.Summer precipitations anomalies exhibit remarkably interannual variation periods of about 3 and 7 years.