【作者】 张皓； 冯利平；

【Author】 ZHANG Hao1,2,FENG Li-Ping1(1.College of Resources and Environmental Sciences,China Agricultural University,Beijing 100193,China;2.Shanghai Climate Center,Shanghai 200030,China)

【机构】 中国农业大学资源与环境学院； 上海市气候中心；

【摘要】 利用华北地区(京、津、晋、冀、鲁、豫)92个气象台站近50年的逐日气象数据,采用趋势分析法和小网格法分析华北地区降水量的时空变化规律,并利用GIS工具实现空间分异表达。结果表明:华北地区降水相对较少,年均降水量为614mm。年均降水量呈由东南向西北逐渐减少的趋势。春季降水纬向分布明显,而夏季降水经向分布更为突出,秋冬季降水与年降水分布相似。随着年降水量由多到少变化,多雨区由东部沿海向南部地区移动,少雨区呈由中西部地区向中北部地区移动的趋势。该区降水年际变异性强,年降水和夏季降水均呈明显的降低趋势,春季降水略呈升高趋势,冬季降水升高趋势更为明显。1980年为由多雨期向少雨期的转折点,降水量存在8-10年的显著振荡周期。60年代为月降水正距平出现最多的时期,而80年代和90年代为月降水负距平出现最多的时期。华北地区降水量季节性差异明显,夏季降水集中,全年65%～85%降水量集中在6～9月。更多还原

【Abstract】 Taking daily data of recent 50 years from 92 weather stations in North China Region,the Characteristics of Spatio-temporal Variation of Precipitation was analyzed using grid spot method and trend analysis.Results showed:There is relatively less precipitation in North China with the average annual precipitation of 614mm.The average annual precipitation has presented the reduced trend from southeast to the Northwest in the past 50 years.There is an obvious latitudinal trend distribution of precipitation in spring and longitudinal trend distribution in summer,while distribution of precipitation in autumn and winter is more similar with which of average annual rainfall.With changing of annual precipitation from more to less,the high precipitation belt has presented the moving trend from east coastal to southern areas,while lack precipitation belt has presented the moving trend from central and west to central and north area.There is strong yearly variability of precipitation in North China.The annual and summer rainfall has presented an obvious reducing tendency,the spring precipitation has presented a slightly increasing tendency,and the precipitation in autumn and winter has presented more obvious tendency.There exists a remarkable vibration cycle of precipitation about 8-10 years.Year 1980 is the turning point from ample to scanty rainy period.Most positive anomalies of mean monthly precipitation occurred in 1960s and most negative anomalies of mean monthly precipitation occurred in 1980s and 1990s.The seasonal difference of precipitation in North China is obvious.Precipitation is centralized in summer.The 65%-85% of whole year’s precipitation is concentrated in June-September.更多还原