年代际太平洋涛动对北大西洋和东太平洋热带气旋活动的影响

Impact of the Interdecadal Pacific Oscillation on Tropical Cyclone Activity in the North Atlantic and Eastern North Pacific.

作者信息

Li Wenhong, Li Laifang, Deng Yi

机构信息

Earth and Ocean Sciences, Nicholas School of the Environment, Duke University, Durham, North Carolina, USA.

School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA.

出版信息

Sci Rep. 2015 Jul 24;5:12358. doi: 10.1038/srep12358.

DOI:10.1038/srep12358

PMID:26205462

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC4648449/

Abstract

Tropical cyclones (TCs) are among the most devastating weather systems affecting the United States and Central America (USCA). Here we show that the Interdecadal Pacific Oscillation (IPO) strongly modulates TC activity over the North Atlantic (NA) and eastern North Pacific (eNP). During positive IPO phases, less (more) TCs were observed over NA (eNP), likely due to the presence of stronger (weaker) vertical wind shear and the resulting changes in genesis potential. Furthermore, TCs over NA tend to keep their tracks more eastward and recurve at lower latitudes during positive IPO phases. Such variations are largely determined by changes in steering flow instead of changes in genesis locations. Over the eNP, smaller track variations are observed at different IPO phases with stable, westward movements of TCs prevailing. These findings have substantial implications for understanding decadal to inter-decadal fluctuations in the risk of TC landfalls along USCA coasts.

摘要

热带气旋是影响美国和中美洲（USCA）的最具破坏性的天气系统之一。在此我们表明，年代际太平洋涛动（IPO）强烈调节北大西洋（NA）和北太平洋东部（eNP）的热带气旋活动。在IPO正相位期间，北大西洋观测到的热带气旋较少（北太平洋东部较多），这可能是由于存在更强（更弱）的垂直风切变以及由此产生的生成潜力变化。此外，在IPO正相位期间，北大西洋的热带气旋往往使其路径更偏东，并在较低纬度处转向。这种变化在很大程度上由引导气流的变化而非生成位置的变化决定。在北太平洋东部，不同IPO相位观测到的路径变化较小，热带气旋主要稳定向西移动。这些发现对于理解美国和中美洲沿海热带气旋登陆风险的年代际到年代际波动具有重要意义。