采用A-Train系列卫星的AURA/MLS水汽、温度资料,CALIPSO/CALIOP云物理资料,结合ECMWF气象再分析资料,分析了东亚地区云顶高于对流层顶事件（Cloud Top Above the Tropopause,CTAT）的区域分布,及其对上对流层—下平流层（Upper Troposph...采用A-Train系列卫星的AURA/MLS水汽、温度资料,CALIPSO/CALIOP云物理资料,结合ECMWF气象再分析资料,分析了东亚地区云顶高于对流层顶事件（Cloud Top Above the Tropopause,CTAT）的区域分布,及其对上对流层—下平流层（Upper Troposphere and Lower Stratosphere,UTLS）水汽和温度结构的影响。结果表明：亚洲季风区的夏季CTAT发生率是30%~55%,为全球最强区域;东北亚的夏季CTAT发生率是15%~20%,为中纬度最强分布区。以CTAT为指标的合成结果表明：15~30°N的东亚—西太平洋UTLS,水汽呈＂上干下湿＂的异常分布,温度呈＂上冷下暖＂的异常分布,该结构与该区域热带气旋合成的结果一致,说明热带气旋是该区域CTAT形成的主要天气系统;35~50°N的东北亚UTLS,水汽呈＂上干下湿＂的异常分布,温度呈＂上暖下冷＂的异常分布,该结构与该区域温带气旋合成的结果一致,说明温带气旋是该区域CTAT形成的主要天气系统。展开更多
【目的】研究超强台风“利奇马”快速增强过程中的海洋响应。【方法】利用中尺度WRF(The Weather Research and Forecasting)模式模拟超强台风“利奇马”,结合中国气象局热带气旋最佳路径数据集和欧洲哥白尼全球海洋物理再分析资料,分...【目的】研究超强台风“利奇马”快速增强过程中的海洋响应。【方法】利用中尺度WRF(The Weather Research and Forecasting)模式模拟超强台风“利奇马”,结合中国气象局热带气旋最佳路径数据集和欧洲哥白尼全球海洋物理再分析资料,分析台风在快速增强过程中的海洋响应。【结果】在台风“利奇马”快速增强过程中,海表面温度呈下降趋势,约-1.3℃/d,且降温范围向周围扩大;热带气旋路径区域海平面高度呈负异常;台风内核热带气旋热势(Tropical Cyclone Heat Potential,TCHP)显著降低,而在远离台风路径的地区TCHP会增加;海表盐度呈下降趋势,在快速增强结束时达到最低;台风中心附近出现正负速度中心交替现象,呈弧形分布向周围传播,最终消散。【结论】海表面温度和海平面高度负异常会减弱热带气旋快速增强;热带气旋快速增强过程导致的TCHP负异常也会抑制台风增强过程的发展;热带气旋快速增强前后台风内核、外围海域TCHP下降率不一致,外围的下降率在快速增强前大于内核;海表盐度的下降与台风带来的强降雨和强风有关。快速增强期间内核TCHP下降率达到最大,与海表温度、盐度以及海表面风场有良好的对应关系。展开更多
To investigate the stratosphere-troposphere exchange(STE)process induced by the gravity waves(GWs)caused by Typhoon Molave(2020)in the upper troposphere and lower stratosphere,we analyzed the ERA5 reanalysis data prov...To investigate the stratosphere-troposphere exchange(STE)process induced by the gravity waves(GWs)caused by Typhoon Molave(2020)in the upper troposphere and lower stratosphere,we analyzed the ERA5 reanalysis data provided by the European Centre for Medium-Range Weather Forecasts and the CMA Tropical Cyclone Best Track Dataset.We also adopted the mesoscale forecast model Weather Research and Forecasting model V4.3 for numerical simulation.Most of the previous studies were about typhoon-induced STE and typhoon-induced GWs,while our research focused on the STE caused by typhoon-induced gravity waves.Our analysis shows that most of the time,the gravity wave signal of Typhoon Molave appeared below the tropopause.It was stronger on the east side of the typhoon center(10°-20°N,110°-120°E)than on the west side,suggesting an eastward tilted structure with height increase.When the GWs in the upper troposphere and lower stratosphere region on the west side of the typhoon center broke up,it produced strong turbulence,resulting in stratosphere-troposphere exchange.At this time,the average potential vorticity vertical flux increased with the average ozone mass mixing ratio.The gravity wave events and STE process simulated by the WRF model were basically consistent with the results of ERA5 reanalysis data,but the time of gravity wave breaking was different.This study indicates that after the breaking of the GWs induced by typhoons,turbulent mixing will also be generated,and thus the STE.展开更多
文摘采用A-Train系列卫星的AURA/MLS水汽、温度资料,CALIPSO/CALIOP云物理资料,结合ECMWF气象再分析资料,分析了东亚地区云顶高于对流层顶事件（Cloud Top Above the Tropopause,CTAT）的区域分布,及其对上对流层—下平流层（Upper Troposphere and Lower Stratosphere,UTLS）水汽和温度结构的影响。结果表明：亚洲季风区的夏季CTAT发生率是30%~55%,为全球最强区域;东北亚的夏季CTAT发生率是15%~20%,为中纬度最强分布区。以CTAT为指标的合成结果表明：15~30°N的东亚—西太平洋UTLS,水汽呈＂上干下湿＂的异常分布,温度呈＂上冷下暖＂的异常分布,该结构与该区域热带气旋合成的结果一致,说明热带气旋是该区域CTAT形成的主要天气系统;35~50°N的东北亚UTLS,水汽呈＂上干下湿＂的异常分布,温度呈＂上暖下冷＂的异常分布,该结构与该区域温带气旋合成的结果一致,说明温带气旋是该区域CTAT形成的主要天气系统。
文摘【目的】研究超强台风“利奇马”快速增强过程中的海洋响应。【方法】利用中尺度WRF(The Weather Research and Forecasting)模式模拟超强台风“利奇马”,结合中国气象局热带气旋最佳路径数据集和欧洲哥白尼全球海洋物理再分析资料,分析台风在快速增强过程中的海洋响应。【结果】在台风“利奇马”快速增强过程中,海表面温度呈下降趋势,约-1.3℃/d,且降温范围向周围扩大;热带气旋路径区域海平面高度呈负异常;台风内核热带气旋热势(Tropical Cyclone Heat Potential,TCHP)显著降低,而在远离台风路径的地区TCHP会增加;海表盐度呈下降趋势,在快速增强结束时达到最低;台风中心附近出现正负速度中心交替现象,呈弧形分布向周围传播,最终消散。【结论】海表面温度和海平面高度负异常会减弱热带气旋快速增强;热带气旋快速增强过程导致的TCHP负异常也会抑制台风增强过程的发展;热带气旋快速增强前后台风内核、外围海域TCHP下降率不一致,外围的下降率在快速增强前大于内核;海表盐度的下降与台风带来的强降雨和强风有关。快速增强期间内核TCHP下降率达到最大,与海表温度、盐度以及海表面风场有良好的对应关系。
基金Guangdong Basic and Applied Basic Research Foundation(2023A1515011323)National Natural Science Foun-dation of China(42130604,42130605,72293604)+4 种基金Guangdong Provincial Observation and Research Station for Tropical Ocean Environment in Western Coastal Waters(GSTOEW)First-Class Discipline Plan of Guangdong Province(080503032101,231420003)Fundamental Research Funds for the Central Universities(202362001,202072010)China Scholarship Council(202208440223)Natural Science Foundation of Shanghai(23ZR1473800)。
文摘To investigate the stratosphere-troposphere exchange(STE)process induced by the gravity waves(GWs)caused by Typhoon Molave(2020)in the upper troposphere and lower stratosphere,we analyzed the ERA5 reanalysis data provided by the European Centre for Medium-Range Weather Forecasts and the CMA Tropical Cyclone Best Track Dataset.We also adopted the mesoscale forecast model Weather Research and Forecasting model V4.3 for numerical simulation.Most of the previous studies were about typhoon-induced STE and typhoon-induced GWs,while our research focused on the STE caused by typhoon-induced gravity waves.Our analysis shows that most of the time,the gravity wave signal of Typhoon Molave appeared below the tropopause.It was stronger on the east side of the typhoon center(10°-20°N,110°-120°E)than on the west side,suggesting an eastward tilted structure with height increase.When the GWs in the upper troposphere and lower stratosphere region on the west side of the typhoon center broke up,it produced strong turbulence,resulting in stratosphere-troposphere exchange.At this time,the average potential vorticity vertical flux increased with the average ozone mass mixing ratio.The gravity wave events and STE process simulated by the WRF model were basically consistent with the results of ERA5 reanalysis data,but the time of gravity wave breaking was different.This study indicates that after the breaking of the GWs induced by typhoons,turbulent mixing will also be generated,and thus the STE.
