北太平洋海温场与我国西北地区春季沙尘暴的关系

通过聚类分析,将我国355个气象站1954～1998年春季沙尘暴发生频率的变化进行分类,在此基础上得到两个沙尘暴指数,利用其探讨了我国西北地区沙尘暴的发生与北太平洋海温的关系.结果发现,当加利福尼亚海温偏低,黑潮及北温带区域海温偏高时,我国黄河以北的内蒙古、甘肃、宁夏等地区,春季气温偏低,沙尘暴活动频繁.作者同时探讨了海温变化影响沙尘暴发生的可能原因.

Relationships Between North Pacific Sea Surface Temperatures and Spring Sandstorms in Northwest China

Two sandstorm indices were created by using clustering method to classify the frequencies of spring sandstorms during the period from 1954 to 1998 among 355 meteorological stations in China. The relationships between North Pacific sea surface temperatures (SSTs) and sandstorm indices were analyzed. The results showed that spring mean temperature was lower in the north region of the Yellow River, including the Inner Mongolia, Ningxia and Gansu provinces when the SSTs of the California Current were lower while the SSTs of Kuroshio and North Temperate Zone were higher. In these cases spring sand storms in the north region of the Yellow River were more active. The synoptic-climatological mechanism for the statistical relationships between the SSTs and the frequencies of spring sandstorms in the northwest China were also discussed.