What question did this study set out to answer?

The research aims to understand how Arctic sea ice influences tropical cyclone tracks in the western North Pacific.

February 8, 2026Climate Dynamics0 citations

Seasonal dependence of the impact of Arctic sea ice on tropical cyclone track density over the western North Pacific

LHLan HaiFudan University RZRuifen ZhanFudan University ADAiguo DaiAlbany State University

Key Points

The research aims to understand how Arctic sea ice influences tropical cyclone tracks in the western North Pacific.
Data analysis and modeling from 1979 to 2022
Statistical analyses of sea ice concentration and cyclone track density
Idealized numerical experiments to support findings
Reduced spring sea ice concentration is linked to increased tropical cyclone track density in summer.
In autumn, a dipole in cyclone track density occurs: south increases while north decreases.
Seasonal dependence impacts are established through statistical correlations and modeled interactions.

Abstract

In recent decades, Arctic rapid sea ice loss has emerged as a major factor influencing global weather and climate. However, its impact on tropical cyclone (TC) tracks over the western North Pacific (WNP) remains unclear. Through data analysis and modeling, this study investigates the interannual influence of spring (March–May) sea ice concentration (SIC) in the Barents Sea (SIC-BS) on the TC track density (TCTD) over the WNP in the subsequent summer (June–August) and autumn (September–October) during 1979–2022. Statistical analyses reveal a distinct seasonal dependence: reduced spring SIC-BS is consistently associated with increased TCTD in summer, but with a south-north TCTD dipole (south increased, north decreased) in autumn. Further diagnostic analyses indicate that the loss of spring SIC-BS triggers an eastward-propagating Rossby wave train, leading to a positive geopotential height anomaly over the Russian Far East. The resulting anticyclonic circulation transports cold air towards east of Japan, cooling sea surface through cloud-radiation-sea surface temperature (SST) effect. It also induces an anomalous cyclonic circulation in the southeast of Japan, shifting warm water eastward by tropical westerlies and warming the central equatorial Pacific. In summer, this cooling induces upper-level divergence over the WNP by jet dynamics, thus enhancing TCTD. In autumn, the tropical warm SST intensifies and extends southwestward, enhancing cyclonic anomaly by a Gill-type response and inducing a compensatory anticyclonic anomaly south of Japan. This leads to a south-north dipole pattern in TCTD. Idealized numerical experiments support these mechanisms, establishing a possible linkage between Arctic sea ice variability and WNP TC tracks.

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