Previous work showed that some tropical cyclones （TCs） in the western Pacific Ocean undergo sudden track reversal, and the onset, maintenance and decay of blocking highs （BHs） coexisted with 19 of the studied TCs ...Previous work showed that some tropical cyclones （TCs） in the western Pacific Ocean undergo sudden track reversal, and the onset, maintenance and decay of blocking highs （BHs） coexisted with 19 of the studied TCs with sudden track reversal. In these cases, the phase relations between the BH, the continental high （CH）, the subtropical high （SH） and the suddenly reversed TCs could be classified into types A, B, C and D. Types C and D were the focal point of this follow-up study, in which Typhoon Pabuk （2007） and Lupit （2009） were employed to conduct numerical simulations. The results showed that the reversed tracks of Pabuk （2007） and Lupit （2009） could have been affected by the BH, particularly in terms of the turning location and the trend of movement after turning. Specifically, the two main features for Pabuk （2007） in the BH perturbations were the deflection of its turning point and a distinct anticlockwise rotation. Lupit （2009） deviated to the southwest and finally made landfall in the Philippines, or experienced further eastward movement, in the perturbed BH. The impact mechanisms can be attributed to the change in the vorticity field transported from the BH, leading to an intensity variation of midlatitude systems. BHs may have a positive feedback effect on the strength of the westerly trough （TR）, as indicated by a weakened and strengthened TR corresponding to negative and positive BH perturbations, respectively.展开更多
台风“烟花”于2021年7月22日00时(世界时,下同)在台湾岛东侧突然向北转向,但美国、日本和中国的业务预报均没有正确预报出该过程。基于NCEP/NCAR提供的全球再分析资料(Final Operational Global Analysis,FNL),采用Lanczos滤波方法分...台风“烟花”于2021年7月22日00时(世界时,下同)在台湾岛东侧突然向北转向,但美国、日本和中国的业务预报均没有正确预报出该过程。基于NCEP/NCAR提供的全球再分析资料(Final Operational Global Analysis,FNL),采用Lanczos滤波方法分析发现,台风“烟花”转向前的西行减速主要受到与季风涡旋有关的季节内尺度环境引导气流分量的影响,向北转向及转向后的向北加速则主要受到季风涡旋和台风相互作用导致的天气尺度环境引导气流分量的引导,主要和beta涡旋对旋转、与季风涡旋的合并、以及加强的Rossby波能量频散这3个重要过程有关。台风“烟花”在纬向尺度约3 000 km的季节内尺度季风涡旋北部的偏东气流西移过程中,与季风涡旋相互作用导致beta涡旋对气旋性旋转,通风流经历东南风—东北风—西南风的转变,使得“烟花”向西减速并逐渐向季风涡旋中心移动,并于7月22日00时与季风涡旋合并,加强了Rossby波能量频散,使得“烟花”东南边缘的天气尺度西南风加强,为缓慢移动的“烟花”提供了向北的引导,“烟花”突然向北转向。展开更多
Super Typhoon Hinnamnor(2022)was a rare and unique western North Pacific typhoon,and throughout its lifespan,it exhibited all of the major features that pose current challenges in typhoon research.Specifically,during ...Super Typhoon Hinnamnor(2022)was a rare and unique western North Pacific typhoon,and throughout its lifespan,it exhibited all of the major features that pose current challenges in typhoon research.Specifically,during different stages of its lifespan,it experienced a sudden change of track,underwent rapid intensification,interacted and merged with another vortex,expanded in size,underwent rapid weakening,produced a strong cold wake,exhibited eyewall replacement,and underwent extratropical transition.Therefore,a timely identification and review of these features of Hinnamnor(2022),as reported in this article,will help update and enrich the case sets for each of these scientific issues and provide a background for more in-depth mechanistic studies of typhoon track,intensity,and structural changes in the future.We also believe that Hinnamnor(2022)can serve as an excellent benchmark to quickly evaluate the overall performance of different numerical models in predicting typhoon’s track,intensity,and structural changes.展开更多
运用NCEP/NCAR 0.5°×0.5°再分析格点资料,台风报文资料,从大尺度环境场、越赤道气流、台风扰动能量频散等方面对1013号台风鲇鱼进入南海后出现路径突变转向的物理原因进行深入分析。研究结果表明:(1)"鲇鱼"台...运用NCEP/NCAR 0.5°×0.5°再分析格点资料,台风报文资料,从大尺度环境场、越赤道气流、台风扰动能量频散等方面对1013号台风鲇鱼进入南海后出现路径突变转向的物理原因进行深入分析。研究结果表明:(1)"鲇鱼"台风进入弱环境场后转向关键区内局地风场的变化与台风自身相互作用对台风路径突变有重要影响;(2)台风转向前期越赤道气流的加强对于转向区内的风向变化有积极作用,并且这种作用从对流层低层850 h Pa至中层500 h Pa随高度逐渐增强;(3)台风处于弱环境流场中时,台风运动有沿其自身扰动能量频散形成的波列传波方向移动的趋势。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.41230421)the 973 project(Grant Nos.2015CB452802 and 2013CB430101)of the Ministry of Science and Technology,China
文摘Previous work showed that some tropical cyclones （TCs） in the western Pacific Ocean undergo sudden track reversal, and the onset, maintenance and decay of blocking highs （BHs） coexisted with 19 of the studied TCs with sudden track reversal. In these cases, the phase relations between the BH, the continental high （CH）, the subtropical high （SH） and the suddenly reversed TCs could be classified into types A, B, C and D. Types C and D were the focal point of this follow-up study, in which Typhoon Pabuk （2007） and Lupit （2009） were employed to conduct numerical simulations. The results showed that the reversed tracks of Pabuk （2007） and Lupit （2009） could have been affected by the BH, particularly in terms of the turning location and the trend of movement after turning. Specifically, the two main features for Pabuk （2007） in the BH perturbations were the deflection of its turning point and a distinct anticlockwise rotation. Lupit （2009） deviated to the southwest and finally made landfall in the Philippines, or experienced further eastward movement, in the perturbed BH. The impact mechanisms can be attributed to the change in the vorticity field transported from the BH, leading to an intensity variation of midlatitude systems. BHs may have a positive feedback effect on the strength of the westerly trough （TR）, as indicated by a weakened and strengthened TR corresponding to negative and positive BH perturbations, respectively.
基金supported in part by the National Science Foundation of China (Grant Nos. 42192554, 41876011, 61827901, and 41775065)the National Key Research and Development Program of China (Grant Nos. 2020YFE0201900 and 2022YFC3004200)+2 种基金Shanghai Typhoon Research Foundation (TFJJ202201)S&T Development Fund of CAMS 2022KJ012Basic Research Fund of CAMS 2022Y006
文摘Super Typhoon Hinnamnor(2022)was a rare and unique western North Pacific typhoon,and throughout its lifespan,it exhibited all of the major features that pose current challenges in typhoon research.Specifically,during different stages of its lifespan,it experienced a sudden change of track,underwent rapid intensification,interacted and merged with another vortex,expanded in size,underwent rapid weakening,produced a strong cold wake,exhibited eyewall replacement,and underwent extratropical transition.Therefore,a timely identification and review of these features of Hinnamnor(2022),as reported in this article,will help update and enrich the case sets for each of these scientific issues and provide a background for more in-depth mechanistic studies of typhoon track,intensity,and structural changes in the future.We also believe that Hinnamnor(2022)can serve as an excellent benchmark to quickly evaluate the overall performance of different numerical models in predicting typhoon’s track,intensity,and structural changes.
文摘运用NCEP/NCAR 0.5°×0.5°再分析格点资料,台风报文资料,从大尺度环境场、越赤道气流、台风扰动能量频散等方面对1013号台风鲇鱼进入南海后出现路径突变转向的物理原因进行深入分析。研究结果表明:(1)"鲇鱼"台风进入弱环境场后转向关键区内局地风场的变化与台风自身相互作用对台风路径突变有重要影响;(2)台风转向前期越赤道气流的加强对于转向区内的风向变化有积极作用,并且这种作用从对流层低层850 h Pa至中层500 h Pa随高度逐渐增强;(3)台风处于弱环境流场中时,台风运动有沿其自身扰动能量频散形成的波列传波方向移动的趋势。
