大气科学学报2026，Vol.49Issue(1)：53-61,9.DOI:10.13878/j.cnki.dqkxxb.20251016002
全球变暖背景下西北、东北太平洋热带气旋频次及生成位置的不同变化特征
Distinctive responses of tropical cyclone frequency and genesis latitude over the western and eastern North Pacific to the global warming trend
摘要
Abstract
Tropical cyclones(TC)are among the most destructive natural hazards worldwide,producing devas-tating winds,torrential rainfall,and storm surges.Under global warming,understanding long-term changes in TC activity and the underlying physical mechanisms is essential for improving prediction and mitigating associated risks.This study investigates two major TC genesis regions——the western North Pacific(WP)and the eastern North Pacific(EP)using observational and reanalysis datasets spanning 1950-2023.We examine changes in TC genesis frequency and latitude,along with the dominant environmental factors modulating these changes. The leading EOF(Empirical Orthogonal Function)mode of global SST(sea surface temperature)is used to derive the principal component time series(PC1),representing the long-term global warming signal.Correlation analyses reveal a significant positive relationship between EP TC genesis frequency and PC1,indica-ting enhanced TC activity in the EP under warming.In contrast,the correlation between WP and PC1 is negative but not statistically significant.The mean latitude of TC genesis exhibits a significant northward shift over the WP but a significant southward shift over the EP,both closely linked to PC1. Neither the genesis potential index(GPI)nor the dynamical genesis potential index(DGPI)effectively cap-tures these observed long-term changes,suggesting limitations in traditional metrics under a warming climate.Fur-ther diagnostic analyses show that environmental zonal vertical wind shear plays a pivotal role in producing the contrasting TC frequency trends.Increasing westerly shear over the WP suppresses disturbance amplification and reduces TC formation,whereas increasing easterly shear over the EP enhances the growth of precursor disturbances and increases TC frequency.Moreover,basin-specific meridional gradients in atmospheric stability and vertical wind shear largely determine the direction and magnitude of TC genesis latitude shifts.Over the WP,stronger stability increases to the south,and reduced shear to the north favors a northward migration of genesis lo-cations.Over the EP,a greater increase in atmospheric stability to the north leads to a southward shift. A linear regression model based on zonal wind shear successfully reproduces the observed trends in TC gene-sis frequency in both basins.Similarly,a multivariate regression model incorporating atmospheric stability and ver-tical wind shear captures the observed shifts in TC genesis latitude,lending further support to the proposed mecha-nisms.Overall,the results highlight the central role of large-scale environmental shear and stability in shaping ba-sin-dependent TC responses to global warming.关键词
热带气旋频率/热带气旋纬度位置/西北太平洋热带气旋/东北太平洋热带气旋/环境气象场Key words
tropical cyclone frequency/tropical cyclone genesis latitude/tropical cyclone over the western North Pacific/tropical cyclone over the eastern North Pacific/environmental meteorological field引用本文复制引用
李天明,耿奕琳..全球变暖背景下西北、东北太平洋热带气旋频次及生成位置的不同变化特征[J].大气科学学报,2026,49(1):53-61,9.基金项目
国家自然科学基金项目(42088101) （42088101）
