向外长波辐射与我国华北地区旱涝关系的初步研究

A PRELIMINARY ANALYSIS ON THE RELATIONSHIP BETWEEN OUTGOING LONGWAVE RADIATION AND DROUGHT/FLOOD OVER NORTH CHINA

本文采用1974—1986年的向外长波辐射(OLR)和华北地区降水资料,对该地区旱、涝年的 OLR 场的时空分布特征进行了研究。分析指出,旱年与涝年的前冬和夏季在 OLR 距平场上呈相反的配置。同时发现,赤道中太平洋和海洋陆地上的 OLR 变化会影响华北旱涝的分布趋势。另外,谱分析计算结果指出,当存在准二年周期时,华北地区降水和赤道中太平洋地区的OLR 之间有较高的凝聚值,呈正位相振荡。而且后者变化较前者超前大约10个月。

Based on the outgoing longwave radiation(OLR)data and precipitation data from 17 stationsin north China during 1974 through 1986,the temporal and spatial distribution features of theOLR anomaly patterns corresponding to drought or flood cases over north China have been dis-cussed in this paper.It is pointed out that the disposal of the OLR anomaly patterns between thedrought and flood cases during the pre-winter or the summer is quite different,and the evolutionof the OLR over two key regions,the equatorial central Pacific and the marine continent,can in-fluence the distribution of the drought or flood in north China.By carrying out the multi-spectral analysis between the precipitation over north China andthe OLR field over the equatorial central Pacific,a common quasi-biennial oscillations is signifi-cant,and the OLR field appears ten months prior to the precipitation.