摘要
近45 a来中国西北夏季干湿的长期变化趋在不同的分区内有所差异,但位于西北西部的地区目前正处于偏湿阶段,而西北东部的地区目前正处于偏干阶段,同时整个西北地区近45 a来偏旱的年份多于偏湿的年份;东亚大槽比较稳定、深厚、新疆脊强,副热带高压偏东偏南是中国西北干旱年500 hPa高度场的显著特点,而东亚大槽比较浅薄、新疆脊比较弱,副热带高压偏西偏北是湿润年500 hPa高度场的显著特点。
There are defferent trends of summer precipitation change between the sub - regions of Northwest China in recent 45a. The west of Northwest China is at a wet phase, but the east at dry phase. The dry years are more than the wet years in the whole region. The distinct characteristic of 500 hPA of dry year is that East Asia trough is steadier and deeper, the Xinjiang ridge is stronger and the Sub - tropical High is easterlier and southlier. by contraries, there will be wet year.
出处
《山西气象》
2007年第2期15-17,共3页
Shanxi Meteorological Quarterly
关键词
干旱指数
干湿特征
环流特征
Drought index
Dry/wet Characteristic
Circulation characteristic
