两类El Ni■o事件对华南前汛期降水异常的影响  

INFLUENCES OF TWO TYPES OF EL NINO EVENTS ON PERCIPITATION ANOMALIES IN THE APRIL-JUNE RAINY SEASON OVER SOUTH CHINA

作　　者：李海燕 孙家仁 谌志刚 梁之彦 钟水新[3] 叶希莹 LI Hai-yan;SUN Jia-ren;CHEN Zhi-gang;LIANG Zhi-yan;ZHONG Shui-xin;YE Xi-ying(Guangzhou Meteorological Observatory,Guangzhou 511430,China;Key Laboratory of urban ecological Environmental Simulation and protection of Ministry of Environmental Protection,South China Institute of Environmental Sciences,the Ministry of Ecology and Environment of PRC,Guangzhou 510655,China;Guangdong Province Key Laboratory of Regional Numerical Weather Prediction,Institute of Tropical and Marine Meteorology,CMA,Guangzhou 510641,China)

机构地区：[1]广州市气象台,广东广州511430 [2]生态环境部华南环境科学研究所/国家环境保护城市生态环境模拟与保护重点实验室,广东广州510655 [3]中国气象局广州热带海洋气象研究所/广东省区域数值天气预报重点实验室,广东广州510641

出　　处：《热带气象学报》2019年第4期491-503,共13页Journal of Tropical Meteorology

基　　金：国家自然科学基金面上项目（41475140、41375092）;广东省自然科学基金重点项目（2016A030311007）;广州市科技计划项目(201804020038);广东省气象局科学技术研究项目（GRMC2017M19）共同资助

摘　　要：利用观测资料及模式结果探讨了EP/CP El Nino事件对华南前汛期(4-6月)降水异常的影响。结果发现,EP和CP型相关的华南前汛期降水异常分布之间存在明显月际差异,表现为4、5月EP(CP)型相关的降水异常以偏多(少)为主;6月则相反,EP(CP)型的降水呈负(正)异常分布。分析表明,EP型相关的4、5月偏强的副热带高压与850hPa上西北太平洋反气旋异常相配合,有利于水汽从海洋向陆地输送,且两广地区水汽辐合,降水异常偏多;而6月相关的500hPa异常场上对应偏强的东亚大槽,不利于水汽输送,且广东地区处于水汽辐散区,对应降水偏少。CP型相关的4、5月对应500hPa上东亚大槽偏强,不利于水汽往陆地输送,且华南为水汽辐散,降水偏少;6月的500hPa上呈现“+-+”的东亚-太平洋遥相关波列(EAP)型,华南地区为明显的水汽辐合,降水偏多。GFDL模式较好地再现了EP/CP型的4、5月降水异常分布及大气环流形势,但是对6月的模拟存在一定偏差。The influence of EP/CP El Nino events on abnormal precipitation in the April to June rainy season of south China is discussed by using observation data and model results.The research results show that there are significant monthly differences in the EP/CP related precipitation anomaly distribution in the April-June rainy season of south China.EP(CP)type related precipitation anomalies are mainly more(less)than the average in April and May;on the contrary,EP(CP)type related precipitation anomalies are less(more)in June.EP(CP)precipitation follows negative(positive)abnormal distribution in June.The analysis shows that EP-type related strong subtropical high in April and May is matched with the anticyclone anomaly of the northwest Pacific Ocean at 850 hPa,which is conducive to the transport of water vapor from the sea to the land due to the water vapor convergence between neighboring regions of Guangdong and Guangxi,and the amount of precipitation is much higher than normal.The East Asian trough of the 500 hPa anomaly is abnormally strong in June,which is not conducive to water vapor transport,and correspondingly,the amount of precipitation is relatively low due to the fact that Guangdong is located in the water vapor divergence zone.In April and May,the CP type related East Asian trough of 500 hPa is relatively strong,which is not conducive to water vapor transportation to land,and precipitation is less because south China region is in the state of water vapor divergence;in June,the“+-+”East Asia-Pacific remote correlation(EAP)type exists at 500 hPa,and the south China region receives heavy precipitation due to its obvious water vapor convergence.The GFDL model can well reproduce the abnormal distribution of the EP/CP type precipitation and atmospheric circulation situation in April and May,but there is some deviation in the simulation of June.

关 键 词：EL NINO事件 CP EL NINO事件 华南 前汛期降水异常 

分 类 号：P732[天文地球—海洋科学]