Confronting Contemporary Seasonality Changes in East Asian Tropical Cyclone Landfalls with a Multi-Century Historical Baseline

Abstract

Paleoclimate records provide a critical long-term perspective on natural climate variability, essential for understanding contemporary climate change. However, existing paleoclimate proxies lack the spatial-temporal coverage for studying changes in high-impact weather extremes like tropical cyclones (TCs). Here we introduce a multi-source framework that confronts the contemporary changes in TC landfalls in East Asia with a multi-century baseline (1368-1911) reconstructed from historical documents. Leveraging pre-industrial and contemporary data, the analysis reveals that a relatively small shift toward earlier landfalls in the contemporary era (1946-2020). However, this shift falls well within the range of natural fluctuations documented historically (1651-1900). This low signal-to-noise ratio indicates the forced anthropogenic signal of TC landfall timing remains challenging to detect. Besides providing a template for assessing seasonality changes in extremes, our work shows consistent natural controls of TC timing in contemporary and pre-industrial eras, lending credibility to pre-industrial observational datasets and climate simulations.