摘要
采用低通滤波和功率谱分析的方法,分析了黄河中下游地区旱、涝年500hPa 高度场的30—60天周期的低频振荡.从1986年和1988年的分析结果看出:在旱年的夏季,乌拉尔山地区的低频振荡周期短、谱值高;贝加尔湖地区的低频振荡周期长、谱值高;副热带地区的低频振荡周期短、谱值低.相反,在涝年的夏季,乌拉尔山地区、贝加尔湖地区和副热带地区的低频振荡具有与旱年相反的特征.
The methods of band-pass filter and power spectrum are used to analyse atmospher-ic low frequency oscillation (LFO) (30—60 days) characteristics of 500hPa geopotentialheight field over the Northern Hemisphere in typical drought/flood year in the low andmiddle reaches of Huanghe River.The facts can be drawn as follows:The characteris-tics of LFO in summer drought appear that longer period and higher spectrum value oc-curred in Bejkal Lake region and shorter period and lower spectrum value in Ural,whilethe characteristics of LFO in flood year in Ural,Bajkal lake and subtropical regions arecontrary to those in drought year.
出处
《应用气象学报》
CSCD
北大核心
1993年第4期402-407,共6页
Journal of Applied Meteorological Science