西太平洋暖池热状态变异及其邻近地区对流活动特征  

Variability of the thermal state of the western Pacific warm pool and the characteristics of its adjacent convective activities

作　　者：李业进 王黎娟[1] 

机构地区：[1]南京信息工程大学气象灾害教育部重点实验室/气候与环境变化国际合作联合实验室/气象灾害预报预警与评估协同创新中心/气候模拟与预测科技创新团队,江苏南京210044 [2]泗阳县环保局,江苏宿迁223700

出　　处：《大气科学学报》2016年第2期156-165,共10页Transactions of Atmospheric Sciences

基　　金：国家重点基础研究发展计划(973计划)项目(2012CB417403);江苏省高校自然科学研究重大项目(14KJA170004);江苏省自然科学基金项目(BK20131432)

摘　　要：利用1981—2011年共31 a夏季的GODAS月平均次表层海温资料,以5~366 m次表层垂直平均海温表征西太平洋暖池热含量,分析了西太平洋暖池热状态变异及其邻近区域对流活动特征。结果表明：1）暖池区热含量异常变化最大,其季节变化与海表温度季节变化高度一致,年际变率大于海表温度的年际变率。2）暖池热状态以整体一致性正异常为主,其时间系数较好地体现了暖池区次表层热状况的年际变异特征。3）暖池邻近地区对流活动与暖池热状态异常密切相关：当暖池偏暖（冷）时,菲律宾周围关键区对流活动显著增强（减弱）,并且该关键区的对流活动受暖池热含量的影响可以追溯至前一年7月一直持续到当年9月。4）暖池热状态异常引起菲律宾周围关键区对流活动异常,进而激发出东亚地区夏季500 h Pa高度场上自低纬度到中高纬度正、负、正的东亚—太平洋（EAP）遥相关型分布特征;暖池暖（冷）异常时对流层低层在菲律宾以东洋面形成一个异常的反气旋性（气旋性）偏差环流。The variability of the thermal state over the western Pacific warm pool（ WP） and the characteristics of its adjacent convective activities were studied using the monthly subsurface sea temperature data of GODAS from1981 to 2011,together with a variety of statistical methods. The heat content（ HC） was defined as the subsurface vertical temperature averaged from 5 to 366 m. The results demonstrate that：（ 1） The WP area is the place where the HC has its largest variability,and its maximum value can reach 1. 2℃ which is equivalent to the variation in SST. The depth layer from 100 to 200 m is the largest in terms of the change in subsurface temperature,usually changing from- 4. 0 ℃ to 4. 0 ℃ Its seasonal variation is highly consistent with SST,and its interannual variability is much greater than that of SST. There is a certain degree of contribution to the HC from the SST of the WP. The thermal condition of the WP is closely related with ENSO events,as the largest cold（ warm） SST anomalies correspond to El Nio（ La Nia） events in the ENSO cycle.（ 2） The dominant mode of HC is one of positive anomalies,and its corresponding time coefficient（ PC1）shows evident annual variability in the sub-layer heat condition over the WP. A heat content index（ HCI） was constructed by using the HC averaged over the WP region. Then,five colder years（ HCI smaller than- 1） and six warmer years（ HCI larger than 1） were identified from the total 31 years,with the total abnormal years accounting for 1 /3 of the whole period.（ 3） There is a close relationship between the convective activities nearby the WP and the abnormal thermal state there in summer. The area of（ 16—26°N,126—146°E） around the Philippines was chosen as the key area to reflect the characteristics of convection of the adjacent areas of the WP,revealing that the convective activities over this critical region significantly enhance（ weaken） when the WP is warmer（ colder）. The fact that convective activiti

关 键 词：西太平洋暖池 热状态 热含量 对流活动 

分 类 号：P461.2[天文地球—大气科学及气象学]