基于Canny边缘检测的热带气旋尺度估计方法

Estimating Tropical Cyclone Size in the Northwestern Pacific Based on Canny Edge Detection

摘要: 热带气旋是影响西北太平洋地区最重要的灾害性天气系统之一，不同尺度的热带气旋对周围环境的影响不同，估计热带气旋的尺度和强度对于预测热带气旋的潜在影响具有重要意义。本文基于国际气候管理最佳路径数据集(IBTrACS)与ERA5再分析数据，利用Canny边缘检测与霍夫圆检测方法提取不同高度层的尺度特征。研究结果表明：热带气旋最大气压梯度半径在空间分布及季节变化上均与强度存在一定相关性，其垂直结构呈现“收紧–扩张–再收紧”的特征，不同强度等级气旋在结构上存在显著差异。结构紧凑且垂直一致性较强的气旋更易发生快速增强，表明结构特征对气旋发展具有重要指示意义。研究成果为理解热带气旋结构特征与强度演变之间的关系提供了新的视角。

Abstract: Tropical cyclones are among the most significant weather hazards affecting the Northwestern Pacific region. Cyclones of different sizes exert varying influences on their surrounding environment; therefore, accurate estimation of tropical cyclone size and intensity is of great importance for assessing their potential impacts. In this study, the International Best Track Archive for Climate Stewardship (IBTrACS) dataset and the ERA5 reanalysis data are utilized, and scale-related features at multiple vertical levels are extracted using the Canny edge detection and Hough circle transform methods. The results indicate that radius of maximum geopotential gradient exhibits a certain degree of correlation with intensity in terms of both spatial distribution and seasonal variability. The vertical structure shows a characteristic pattern of “contraction-expansion-re-contraction,” and significant structural differences are observed among cyclones of different intensity categories. Cyclones with more compact structures and stronger vertical coherence are more prone to rapid intensification, suggesting that structural characteristics provide important indicators for cyclone development. Overall, this study offers a new perspective for understanding the relationship between tropical cyclone structural characteristics and intensity evolution.