基于探空数据的飓风垂直风速特征研究
Vertical Velocity Characteristics of Hurricanes Based on Dropsondes Data
孙尧 1李煜斌 2汤杰 3高志球 2尹剑 4吴宇杰2
作者信息
- 1. 南京信息工程大学,江苏 南京 210044;天津气象雷达研究试验中心,天津 300061
- 2. 南京信息工程大学,江苏 南京 210044
- 3. 中国气象局上海台风研究所,上海 200030
- 4. 北京城市气象研究院,北京 100089
- 折叠
摘要
基于飞机下投探空数据分析了飓风中大气低层(地面3km内)垂直风速的分布特征.结果表明,飓风近区(归一化半径R/RMW小于5的区域,其中R为下投探空与飓风中心之间的距离,RMW为飓风的最大风速半径)、远区(5≤R/RMW<10的区域)和外区(R/RMW≥10的区域)垂直风的低风速段(垂直风速绝对值<2 m·s-1)随高度分布特征的区别不明显,但高风速段(垂直风速绝对值≥2 m·s-1)在近区出现正值的频次最高,明显多于远区和外区;而在外区出现负值的频次最高,明显多于近区和远区.在飓风近区随着高度的增加上升气流出现的频次降低,而下沉气流出现的频次增多,在飓风远区和外区上升气流的强弱和出现的比例随高度的变化不明显;在飓风近区上升气流的速度和出现的比例随着飓风强度增强而增大,而远区和外区的垂直风中位数速度和出现的比例随飓风强度的变化不明显.此外,观测发现飓风上升气流风速可超过10 m·s-1,通常出现在归一化半径为1～2.5的区域内,且需飓风最大风速达到50 m·s-1以上.
Abstract
Based on observational data collected by dropsondes,this paper analyzed the distribution characteristics of hurricanes'vertical velocity in the lower atmospheric layer(within 3 km of the ground).The results show that smaller vertical velocity(<2 m·s-1)exhibited no significant difference in distribution with height in the near-center region(R/RMW≤5,where Rrepresents the distance between the dropsonde and the center of the hurricane,and RMW denotes the maximum wind speed radius of the hurricane),the far-center region(5≤R/RMW<10)and outside-hurricane region(R/RMW≥10).However,the frequency of positive values of larger vertical velocity(≥2 m·s-1)in the near-center region was the highest,significantly exceeding that in the far-center and outside-hurricane regions.Conversely,the frequency of negative values in the outside-hurricane region was the highest,significantly exceeding that in the near-center and far-center regions.In the near-center region of hurricanes,the frequency of updrafts decreased with the increase in height,while the frequency of downdrafts increased.In the far-center and outside-hurricane regions,the intensity and proportion of vertical velocity did not change obviously with height.The intensity and proportion of updrafts in the near-center region increased with hurricane intensity,while the median velocity and proportion of vertical velocity in the far-center and outside-hurricane regions showed little change with hurricane intensity.Moreover,it is found that the updrafts in hurricanes can exceed 10 m·s-1,usually in the normalized radius of 1-2.5,and the maximum wind speed of the hurricane should reach 50 m·s-1.
关键词
飓风/下投探空/垂直风速/归一化半径/大气低层Key words
hurricane/dropsondes data/vertical velocity/normalized radius/lower atmospheric layer引用本文复制引用
出版年
2024
国家科技期刊平台
NSTL
万方数据