Effects of tropical sea surface temperature variability on Northern Hemisphere tropical cyclone genesis
Effects of tropical sea surface temperature variability on Northern Hemisphere tropical cyclone genesis
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DOI：
10.1175/jcli-d-21-0084.1
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发表时间：
2021-08
影响因子：
4.9
通讯作者：
Shuo Li;W. Mei;S. Xie
中科院分区：
文献类型：
--
作者：
Shuo Li;W. Mei;S. Xie
本文定量分析了北半球暖季热带海表温度（SST）变化对北方半球海盆热带气旋生成频率（TCGF）年际-年代际变化的贡献。热带海温变化的前7个主要模态与典型的厄尔尼诺-南方涛动（ENSO）、全球变暖（GW）、太平洋经向模态（PMM）、大西洋年代际振荡（AMO）、太平洋年代际振荡（PDO）和大西洋经向模态（AMM）有关。1969-2018年，这些模态分别占北大西洋（NA）、东北太平洋（NEP）和西北太平洋（NWP）流域TCGF方差的58%、50%和56%。在北印度洋，SST对TCGF变率的影响很弱。各流域的主导SST模态不同：NA为ENSO、AMO、AMM和GW; NEP为ENSO和AMO; NWP为PMM、年际AMO和GW。一种特定的模式可能会对不同流域的TCGF产生相反的影响，特别是在NA和NEP之间。滑动窗口多元线性回归分析表明，在北大西洋和数值预报中，海温对全流域TCGF的影响在时间上是稳定的，而在北太平洋，海温对全流域TCGF的影响在20世纪70年代中期以后有所加强。本文还探讨了海温对热带气旋生成和发生频率的影响，并通过诊断生成潜力指数及其分量来检验其物理机制。
This study quantifies the contributions of tropical sea surface temperature (SST) variations during the boreal warm season to the interannual-to-decadal variability in tropical cyclone genesis frequency (TCGF) over the Northern Hemisphere ocean basins. The first seven leading modes of tropical SST variability are found to affect basin-wide TCGF in one or more basins, and are related to canonical El Niño–Southern Oscillation (ENSO), global warming (GW), the Pacific Meridional Mode (PMM), Atlantic Multidecadal Oscillation (AMO), Pacific Decadal Oscillation (PDO) and Atlantic Meridional Mode (AMM). These modes account for approximately 58%, 50% and 56% of the variance in basin-wide TCGF during 1969–2018 over the North Atlantic (NA), Northeast Pacific (NEP) and Northwest Pacific (NWP), respectively. The SST effect is weak on TCGF variability in the North Indian Ocean. The dominant SST modes differ among the basins: ENSO, the AMO, AMM and GW for the NA; ENSO and the AMO for the NEP; and the PMM, interannual AMO and GW for the NWP. A specific mode may have opposite effects on TCGF in different basins, particularly between the NA and NEP. Sliding-window multiple linear regression analyses show that the SST effects on basin-wide TCGF are stable in time in the NA and NWP, but strengthen after the mid-1970s in the NEP. The SST effects on local TC genesis and occurrence frequency are also explored, and the underlying physical mechanisms are examined by diagnosing a genesis potential index and its components.