1961-2008年东北三省地面气压变化特征

Change of Surface Pressure in Northeast China during 1961-2008

利用1961-2008年逐月观测资料,分析了东北三省年和季平均地面气压变化的时空特征。结果表明:(1)整个时期东北三省年平均地面气压变化趋势不很明显,1961-1990年呈递增趋势,1991-2008年呈明显的递减趋势,变化速率达-0.32hPa.(10a)-1,通过了0.05显著性水平检验;(2)1961-2008年东北三省各季平均地面气压变化趋势存在差异,春、秋季地面气压呈递减趋势,夏、冬季呈递增趋势,其中春、夏季均通过了0.05显著性水平检验;(3)年平均地面气压的变化趋势也存在明显的空间差异,其中辽宁大部、吉林和黑龙江西部一般呈递减趋势,其余地区一般呈递增趋势。(4)东北三省地面气压的变化与西伯利亚高压及研究区域的地面气温变化具有一定联系。

Monthly surface pressure data from 1961 to 2008 are used to study the temporal and spatial changes of surface pressure in three provinces（Liaoning,Jilin and Heilongjiang） of Northeast China.The results show that：（1） The trend of average surface pressure in three provinces of Northeast China is not significant during the whole analyzed period.However,there is an increasing trend in the period of 1961-1990 and a obvious decreasing trend in the period of 1991-2008 with the rate of-0.32 hPa·（10 a）-1,which has passed the significant level of 0.05.（2） The trend of region average surface pressure has seasonal variations,with decreasing trends in spring and autumn,and increasing trends in summer and winter,but the trends in spring and summer have passed the significant level of 0.05.（3） The trend of annual mean surface pressure shows clearly regional differences.In most of Liaoning Province,Jilin Province and the west of Heilongjiang Province surface pressure have appeared a decreasing trend while the rest of the study region has experienced an increasing trend.The change of surface pressure in three provinces of Northeast China might have been related to the weakening of the Siberian High and the increaseing of surface air temperature in the study region.