西北太平洋地区台风环境场的预估研究  

Projection of Typhoon-Related Environmental Fields in the Western North Pacific

作　　者：王一格 姜大膀[2,3] 华维 WANG Yige;JIANG Dabang;HUA Wei(Chengdu University of Information Technology,Chengdu 610225;Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029;University of Chinese Academy of Sciences,Beijing 100049)

机构地区：[1]成都信息工程大学,成都610225 [2]中国科学院大气物理研究所,北京100029 [3]中国科学院大学,北京100049

出　　处：《大气科学》2020年第3期552-564,共13页Chinese Journal of Atmospheric Sciences

基　　金：国家重点研究发展计划项目2016YFA0602401;国家自然科学基金项目41421004。

摘　　要：本文择优选取了国际耦合模式比较计划第五阶段(CMIP5)中19个气候模式的试验数据,预估了RCP4.5和RCP8.5典型浓度路径情景下21世纪末(2080~2099年)西北太平洋地区(0°~40°N,100°E^180°)台风环境场和台风生成潜力指数(IGP)变化。结果表明,相对于1986~2005年参考时段,21世纪末西北太平洋海洋表面温度(SST)增加,垂直风切变(VWS)和向外长波辐射(OLR)均在其与台风频数呈显著负相关的区域减少,有利于台风生成和发展;由大陆向南海延伸的低压系统减弱,不利于台风活动。总体上,在RCP8.5情景下台风环境场的变化较RCP4.5情景相对更大。利用信噪比进一步考察了模式间差异性,SST变化的信噪比在大部分地区大于3.0,在低压系统控制区海平面气压变化的信噪比大于1.0,模式间一致性较好;对于VWS和OLR,信噪比小于0.6,模式间差异较大;但在与台风频数显著负相关的地区,对OLR变化方向的模拟在模式间高度一致。与以上环境场变化相对应,未来西北太平洋IGP显著增加。This study projects the change in environmental fields and the typhoon IGP(genesis potential index) in the western North Pacific(0°–40°N and 100°E–180°) in the late 21st century(2080–2099) using outputs from the RCP(Representative Concentration Pathway) 4.5 and RCP8.5 experiments of CMIP5(Phase 5 of Coupled Model Intercomparison Project), carried out using 19 climate models. These models are capable of reasonably reproducing modern typhoon-related environmental fields and are thus selected for the analysis. Compared with the reference period of1986–2005, there appears to be an increase in SST(sea surface temperature) in the western North Pacific, a weakening of VWS(vertical wind shear), and a decrease in OLR(outgoing long wave radiation) in the key regions where there are significantly negative correlations between these factors and the frequency of the typhoon;this is beneficial for the formation and development of the typhoon. On the contrary, the low pressure system that extends from the mainland to the South China Sea is weakened, suppressing typhoon activities. In general, changes in the typhoon environmental fields in the RCP8.5 scenario are greater than in the RCP4.5 scenario. In addition, the signal-to-noise ratio is examined to measure consistency between individual models. This ratio is found to be greater than 3.0 for SST change and greater than1.0 for sea level pressure in regions under the low pressure system;for VWS and OLR changes, a ratio of less than 0.6 denotes a degree of disagreement between the models. However, the models agree well with the OLR change in regions associated with typhoon activities. The aforementioned changes in the typhoon’s environmental fields are in line with the increase in IGP in the future.

关 键 词：台风 全球变暖 西北太平洋 台风环境场 

分 类 号：P467[天文地球—大气科学及气象学]