El Niño-Southern Oscillation induced migration of typhoon tracks in the northwestern Pacific Ocean over the last two millennia
摘要
Revealing the spatiotemporal relationship between typhoon variability and climate conditions, and accurately predicting typhoon activities, is crucial for improving hazard scenarios in coastal regions. However, the short meteorological record restricts a comprehensive understanding of typhoon variation driven by climate change, necessitating the reconstruction of paleo-typhoons through geological records. In this study, two sediment cores from the East China Sea inner shelf muddy belt, northwestern Pacific, were analyzed to reconstruct the paleo-typhoons quantitatively over the last ∼2000 yr. Our results revealed two periods of increased typhoon activity, namely ∼1.6 to 1.1 ka, and ∼0.5 to 0 ka, which were consistent with La Niña-dominated intervals. Meanwhile, in the East China Sea inner shelf muddy belt, the proportion of silt sediments from Taiwan, whose transport process is dominated by typhoon activities, significantly increased. During La Niña-dominated intervals, the relatively cold Indo-Pacific Warm Pool induced a southwestward migration of typhoons by driving the westward migration of the rising limb of the Walker Circulation and the equatorward contraction of the Hadley Cell. Consequently, more typhoons made landfall in southeast China during La Niña-dominated intervals. In addition, the peak maximum typhoon frequency in southeast China during the Little Ice Age was a consequence of the combined effects of La Niña-like intervals and the contraction and migration of the intertropical convergence zone. Our findings emphasized the force of El Niño-Southern Oscillation phase oscillation on typhoon tracks in the northwestern Pacific over several centuries, and the relative proportion of Taiwan sediments in the shelf muddy belt can reflect the changes in typhoon frequency over longer timescales. These results contribute valuable insights for paleoclimatic, paleoenvironmental, and sedimentological studies in East Asia during the Holocene.