Zhao Jiuwei, Zhan Ruifen, Wang Yuqing, Xie Shang-Ping, Wu Qiong
Department of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences, Fudan University, Shanghai, China.
International Pacific Research Center and Department of Atmospheric Sciences, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, HI, USA.
Sci Adv. 2020 Oct 9;6(41). doi: 10.1126/sciadv.aba6813. Print 2020 Oct.
How much the observed long-term variability of tropical cyclone (TC) activity is due to anthropogenic global warming (GW) or internal climate variability remains unclear, limiting the confidence in projected future change in TC activity. Here, the relative contributions of GW and the Interdecadal Pacific Oscillation (IPO) to the long-term variability of TC track density (TCTD) over the North Pacific (NP) are quantified on the basis of statistical analyses and climate model simulations. Results show that historical GW mainly reduced (increased) TCTD over the western (eastern) NP, while the positive (negative) IPO corresponds to a NP basin-wide increase (decrease) in TCTD except in some coastal regions. The IPO has a much greater impact on TCTD over the western NP than GW, while the IPO and GW impacts are about equal over the eastern NP during 1960-2019. These findings have important implications for projecting future TC activity over the NP.
热带气旋（TC）活动观测到的长期变化在多大程度上归因于人为全球变暖（GW）或内部气候变率仍不明确，这限制了对TC活动未来变化预测的信心。在此，基于统计分析和气候模型模拟，量化了GW和年代际太平洋涛动（IPO）对北太平洋（NP）TC路径密度（TCTD）长期变化的相对贡献。结果表明，历史上的GW主要使NP西部的TCTD降低（增加），而正（负）IPO对应于NP整个海域TCTD的增加（减少），某些沿海地区除外。IPO对NP西部TCTD的影响远大于GW，而在1960 - 2019年期间，IPO和GW对NP东部TCTD的影响大致相当。这些发现对预测NP未来的TC活动具有重要意义。
