摘要
利用日本葵花-8卫星的黑体亮温、ERA5再分析资料和NOAA海表温度等资料,对2002号热带气旋“鹦鹉”的结构非对称特点及近海停止增强的原因进行了分析。结果表明:在南亚高压相对较强、副热带高压相对较弱的环流背景下,热带气旋“鹦鹉”由缓慢加强转为停止增强,其黑体亮温的非对称程度增大。在较大的环境风垂直切变作用下,对流集中分布在环境风垂直切变的下风方;当环境风垂直切变增大到大于阻碍热带气旋发展的阈值(12.5 m/s)时,热带气旋“鹦鹉”随即停止增强。高于28℃的海表温度是热带气旋“鹦鹉”停止增强后维持强度不变的重要前提条件。低层水汽输入减弱而输出增强、高层辐散减弱至小于低层辐合、热带气旋环流中心向南倾斜加剧、低层流入热带气旋南侧的西风分量减弱以及高层热带气旋周围流入热带气旋的北风的分量明显增大不利于热带气旋“鹦鹉”增强,是其在近海停止增强的重要原因。
Using the black body brightness temperature(TBB)data of Japan HMW8 satellite,the reanalysis data of European Center ERA5 and the sea surface temperature(SST)data of NOAA,the asymmetric feature and cause of stopping intensification of tropical cyclone(TC)"Nuri"(2002)over the offshore area of China is analyzed.The results show that TC"Nuri"changes from slow strengthening to stopped strengthening and the asymmetry of its TBB increases under the background of relatively strong South Asian high and relatively weak subtropical high.Under the influence of strong vertical shear of environmental wind,convection is concentrated on its downwind side.TC"Nuri"stops enhancement when the vertical shear of environmental wind increases to be greater than the threshold(12.5 m/s)that hinders the development of TC.The SST above 28℃is an important precondition for TC"Nuri"maintaining its strength after it stops strengthening.The main causes for TC"Nuri"stopping intensification over the offshore of China are the weakening input and enhancing output of the low-level vapor,decreasing of upper-level divergence to be smaller than low-level convergence,the intensified southward inclination of the TC circulation center,and the unfavorable condition for TC intensification due to the weakening of low-level westerly wind component flowing into the south of the TC and the significant increasing of upperlevel northerly wind component flowing into the TC.
作者
覃丽
吴启树
曾小团
吴俞
QIN Li;WU Qishu;ZENG Xiaotuan;WU Yu(Guangxi Meteorological Obserwaton,Narning 530022,China;Fuyjian Meteorological Obserulony Fichou 350001,China;Hainan Meteorological Obsernulor,Haikou 570203,China)
出处
《海洋预报》
CSCD
北大核心
2022年第4期24-36,共13页
Marine Forecasts
基金
广西自然科学基金项目(2022GXNSFAA035482)
福建省自然科学基金项目(2021J01457)。
