基于修正Z指数的黑龙江省旱涝时空特性分析

Spatio-Temporal Characteristics of Drought and Flood in Heilongjiang Province Based on the Revised Z Index

为研究黑龙江省旱涝时空特点,采用三种旱涝指标分析了黑龙江省23个气象站点1960~2015年逐日降水观测资料,并确定Z指数为单站旱涝指标;依据黑龙江省实际情况对Z指数界限值进行修订,并在此基础上分析了黑龙江省近56年旱涝时空特性,之后利用经验正交函数(EOF)进一步分析了黑龙江省旱涝分布空间特征。结果表明,时间上,黑龙江省旱涝交替发生,易发生连续性旱涝灾害,且旱涝存在27年左右的显著周期;空间上,黑龙江省中西部干旱发生次数较多,北部发生次数较少;中部洪涝发生次数较多,东南部及西部部分地区发生次数较少;EOF分析可知黑龙江省旱涝灾害分布类型为全局分布一致型、南北相反型、西北和东南方向相反三种。研究结果可为黑龙江省相关部门制定抗灾对策提供参考。

For study spatio-temporal characteristics of drought and flood in Heilongjiang Province,three kinds of drought and flood index were used to analyze the daily precipitation data of 23 meteorological stations in Heilongjiang Province from 1960 to 2015,and Z Index was chosen as a single station index.According to the actual situation of Heilongjiang Province,the threshold value of Z Index was corrected.And the spatio-temporal characteristics of drought and flood nearly 56 years was analyzed.Then the spatial characteristics distribution of drought and flood in Heilongjiang Province were further analyzed by EOF.The results show that from the point of view of time,droughts and floods alternated in Heilongjiang Province,droughts and floods are prone to continuity and droughts existed significant period of about 27 years;from the perspective of space,more droughts occurred in the midwest of Heilongjiang Province,and there are fewer times in the north of Heilongjiang Province;floods occurred more frequently in the middle of Heilongjiang,the southeast and parts of the west had been less frequent;the EOF analysis shows that droughts and floods in Heilongjiang Province are divided into three types:the same anomaly in whole province,different anomalies between both in north and south,and different anomalies between both in northwest and southeast.The result can provide a reference for the relevant departments of Heilongjiang Province to formulate anti-disaster measures.