中国北部近海超级赤潮与西北太平洋海气相互作用的关联分析

Relation analyses of super red tide in the northern coastal waters of China and western North Pacific air-sea interaction

已有研究揭示气溶胶传输和季风过程对中国近海赤潮的影响.本研究利用统计分析和动力学诊断方法,从海气相互作用的角度探究2000—2021年西北太平洋海温异常对中国北部近海超级赤潮的可能影响.结果表明:晚冬1—2月西北太平洋偶极型海温异常与随后5—6月中国北部近海的超级赤潮显著相关;西北太平洋南部冷-北部暖的偶极子海温异常可持续到随后的5—6月,并引发对流层低层向热带外传播的遥相关波列,使得鄂霍次克海气旋系统形成;该气旋西侧的西北风异常向中国北部近海输送干冷空气,伴随着对流层高层的异常辐合引发干沉降过程,从而为中国北部近海超级赤潮的暴发提供了有利的气象条件.上述结果可为中国北部近海超级赤潮的暴发和预测提供科学参考.

Previous studies have revealed the effect of aerosol transport and monsoon processes on the red tide in the coastal waters of China.Based on the statistical analysis and dynamic diagnosis,this study,from the perspective of air-sea interaction,documented the influence of western North Pacific(WNP)sea surface temperature(SST)anomalies on the super red tide in the northern coastal waters of China(SRT_NCWC)from 2000 to 2021.The results show that SRT_NCWC in May to June significantly correlates with the preceding late winter(January to February)WNP dipole-like(WNPD)SST anomalies.Anomalies of cold southern-warm northern WNPD SST in late winter can be prolonged to the subsequent May to June,which induces a teleconnection wave train propagating to outside of the tropics in the lower troposphere,thereby forming a cyclone system over the Sea of Okhotsk.On the western flank of the cyclone,anomalous northwesterly transports cold-dry airflow to the domain of NCWC,which are accompanied by convergence anomalies of the upper troposphere,resulting in dry sedimentation.Thus,the WNPD SST anomalies coupled with upper and lower circulations,result in the occurrence of SRT_NCWC through the dry sedimentation process.The above results provide a scientific reference for generating and projecting the SRT_NCWC.