Slowdown of typhoon translation speed and its links to the storm poleward migration

Abstract Detecting and interpreting long-term changes in typhoon translation speed in observations remains challenging, contrasting with the increased confidence in the poleward migration of typhoons. Here, I show a significant relationship between the basin-wide translation speed and the latitudinal position of typhoons in the western North Pacific over 1980–2023. There are two key findings. First, because typhoons move faster at higher latitudes, the significant poleward migration (80 km/decade) increases the yearly basin-wide translation speed by 5% over the period. This effect reduces the detectability of a slowing trend in typhoon translation speed. Second, the basin-wide translation speed solely contributed by regional translation speed has significantly slowed by 18%. The translation speed slowdown and the poleward migration are likely caused by the same climate drivers through the interconnected large-scale atmospheric circulation between the tropics and subtropics. My findings suggest exacerbated typhoon-related risk in the subtropical regions in a changing climate.