摘要
利用天津地区12个国家级气象观测站1979-2020年暖季(5-9月)逐分钟降水数据,按2 h间隔提取降水过程,根据降水历时将其划分成短历时、中历时、长历时和持续性降水过程,从降水量、降水强度和频次3个方面来研究其时空演变特征。结果表明:(1)在时间变化上,降水量、降水过程频次及其占比变化较为一致,短历时和中历时降水过程呈增加趋势,长历时和持续性降水过程呈减少趋势;各历时降水强度均有所增加。(2)从季内变化来看,短历时和中历时降水过程的降水量和降水强度大值区的时间范围从传统的“七下八上”扩展到6月中旬-8月下旬,而长历时和持续性降水过程的降水量和降水强度大值区的时间范围变得更为集中。(3)在空间分布上,各历时降水量及降水强度存在不同的空间特征,变化趋势也并不一致。降水的变化主要体现在短历时降水量的增加和持续性降水量的减少,以及对应历时降水强度的增加,这种变化在市区及周边地区和滨海新区尤为显著,可能与城市化导致的城市热环境变化有关。
Different precipitation events are divided into short-duration,medium-duration,long-duration and persistent precipitation at 2-h intervals by minute precipitation data of 12 national meteorological stations in Tianjin during the warm season(from May to September)of 1979-2020.The spatial and temporal variation characteristics of precipitation,intensity and frequency of the precipitation events with different durations are analyzed.The results are shown below.(1)Temporally,the variations of precipitation,precipitation frequency and ratio are consistent,short-and medium-duration precipitation events show an increasing trend,and long-duration and persistent precipitation events show a decreasing trend.The precipitation intensity increases in each duration.(2)The time range of high precipitation and intensity of short-and medium-duration precipitation events has expanded from the traditional“late July-early August”to“mid-June-late August”,while that of long-duration and persistent precipitation events has become more concentrated.(3)There are different spatial characteristics and trends in precipitation and intensity.The change in precipitation is mainly reflected in the increase of short-duration precipitation and the decrease of persistent precipitation,corresponding to the increase in precipitation intensity.This change is particularly significant in urban districts and their surrounding areas as well as in Binhai New area,which may be related to the changes in the urban thermal environment caused by urbanization.
作者
杨艳娟
杨劲
任建玲
YANG Yanjuan;YANG Jin;REN Jianling(Institute of Arid Meteorology,CMA/Key laboratory of Arid Climate Change and Reducing Disaster of Gansu Province/Key Open Laboratory of Arid Climate Change and Disaster Reduction of CMA,Lanzhou 730020,China;Tianjin Climate Center,Tianjin 300074,China;Kazuo County Meteorological Service,Kazuo 122300,China;Tianjin Meteorological Information Center,Tianjin 300074,China)
出处
《海洋气象学报》
2025年第5期111-123,共13页
Journal of Marine Meteorology
基金
干旱气象科学研究基金项目(IAM202416)。
关键词
降水强度
降水过程
暖季
precipitation intensity
precipitation event
warm season
